You're welcome my Friend......It's nice to know that folks still use, and tinker with this old technology......I find that I actually have fun working on Carburetors, as opposed to working on fuel injection with all of that computer, sensor, and actuator kind of stuff......You can usually repair or modify the old school stuff, as opposed to just locate, and replace the faulty parts on the newer fuel injection stuff!
Greetings.....A good place to start in accelerating pump setting/s is to get a hold of the "Spec-Sheet" that you get when you buy a rebuild kit, or factory manual, as there are a multitude of different settings for each Carb/Vehicle/Transmission Application/s........I recall on one of the "4-Speed Manual Transmission" carbs that I worked on had 2 settings that I had to adjust for!!!..........As for your Wavering Idle speed......Sounds like a Vacuum leak or a plugged idle passage perhaps?
Rocky, your videos are very informative and I'm learning a lot about a carb I had previously never heard of. I am in the UK and have a 79 Dodge Sportsman motorhome with a small block 360 motor with a carter thermo quad carb. She runs great for about 30 mins or so then when at hot she will just stumble and die when I put her into drive. New pump fitted today along with filter inline , still the same, could you possibly point me in the right direction, we just want our baby back on the road again lol, thanks
Bulldogcol Greetings Bulldogcol....Thanks for watching, from across the "Pond" (aka, the Atlantic Ocean), b-cuz, I'm over here in Canada eh...lol).................................Now then, You did say, that, You wanted Your "Baby" back on the Road, did You not...???...well...did You remember to "Burp" Her, after She was "Fed"...???...as it might just be, Trapped "Gas"...!!!...lol..................................Lettuce now, get into some "Real-ism", and see if we can get Your "Baby"(that be-in Your 1979 Sportsman Motorhome, that is)...back on the Road....................First thing first...................Have a look-see, for the usually..."4 Numbers, followed by the Letter "S", that You should Find..."Stamped into"...Your Carter Thermoquad Carburetor's..."Throttle Body" (aka, the Lowest, Aluminum/Aluminium, Part, of Your Thermoquad Carb), on the (lowest part), at the "Left Rear", of Your Thermoquad Carburetor, and, once You find those "4 Numbers, followed by the Letter "S" (Hopefully, that is), then, please let me know, what "They" happen to be, if You are able to See "Them", as by doing so, I'll then, have a much better chance, as to just which "Model" of Thermoquad, along with the Addition, or, lack there-of, of any, and all, "Gadgets", that might very well, have be Added Onto, Your particular Thermoquad Carb, over and above, that, of what You "Saw", on my Thermoquad Carburetor, that I used, as a "Movie Prop", in this UA-cam Video of mine, which my Friend, is about as "Basic & Simple", as "They" can be...................................I'll now, give You, a "Few Things", that, can cause, like You were sayin', Your Engine, wanting to Stumble and Die, as in, having the Engine, Stall/Stop Running, once "it" (Your Engine) was Hot....................................Also, this problem, of having Your Engine Stumble/Die, when Hot, did You happen to Notice, if, it "Gradually got Worse", over, quite some Time, or, was it, one of those, "All of a Sudden/without Warning", type of, Problems, that just materialized...???....................................Might be a "Vacuum Leak", as in a Cracked, or (air) Leaking, Rubber, Vacuum Hose, or maybe, even, became Disconnected from its fitting/ connection point, or, quite rarely, a PCV (Positive Crankcase Ventilation) Valve, might get stuck Open, possibly...........................Might be, that Your "Choke Plate" (on top of Your Thermoquad, at the Front of it)..."Is Not Opening Fully/Vertical"....when the Engine is Up to...."Operating Temperature"...???............................If, Your Thermoquad Carb, happens to have, a Curb Idle Speed "Solenoid", that's usually Mounted on the Right Side (as Viewed, while You are sitting in the Drivers seat), at the Front of Your Thermoquad, either the Solenoid itself, is not working as it should, or the, Voltage/Electricity, is not making its way, to that very same Solenoid, which will cause, a Too Low, Curb Idle Speed, in most cases....................................."I've actually had, a PCV Valve, made out of, a Nylon/type of material, Separate into "2 Pieces", while I was Driving, and, when I stopped for a red light, the Engine ran horribly, and almost, Stalled/Quit...until I stuck it back together, made my way Home, and got a New One...!!!...lol..................................Another Time (same Engine), and also, while being Stopped, at a red light, the Engine started to Run, really rough, at Idle Speed, and, what "it" turned out to be, was, a small piece of "Swarf" (lol, maybe they use, or used that term, where You Live), to describe, that small piece of...Debris/Crud/ Yuck-ees...that, as I see/saw it, getting trapped, in my Thermoquad Carb's..."Idle (speed) Circuit/Passageway"...which I actually "Cured", by, Removing both, Idle Mixture Screws, and, by using a length of, good ole, 1/8 Inch/3 mm, inside diameter, Fish Aquarium, Neoprene, clear plastic Tubing, I took one end of it, and held it on, each of the screw-threaded Holes, that the Idle Mixture Screws came out of, and, I Huffed, and I Puffed...(using, good ole Lung Air Pressure, Via my Mouth), to try and Blow/Force, that, or those "Obstructions", that I was Thinkin', that, just might be causin', my Lumpy, Bump-ee, and not wanted, Bad Idling, Engine situation (at the time), and, I'll be Damned, that Huffin' and Puffin', that I did..."Fixed"...my Thermoquad's..."Plugged-Up"....Idle Circuit/Passageway, and, my Engine, was, oh so Happy, after I did so...!!!...lol...................................Now then, when was the "Last Time", that You had Your Baby's (Motorhome....lol), Engine..."Tuned-Up"...as well as, having all of the..."Parts and Pieces"..."Replaced"...as Indicated, in Your Motorhome's..."Owners Manual"...if indeed, You happen to have one, in..."Captivity"...that is (lol)...???....................................................................In order for me, to be able to actually, help You out, the best I can, I really have to know, just..."What"...???..."Ignition System" type...and, Any and All...."Pollution Gadgets/Devices"...both..."Electrically"...and..."Fuel System"..."Related"...are actually..."Installed"...in/on, Your Exact..."Baby/Motorhome"...as, at this particular point in time, I'm only pondering, a reasonable Guess, at, just "What"...???...might be "Included", in the way of, Parts and Pieces/Gadget-tree, that, actually "Make-Up", Your "Baby" (Your Motorhome, that is)...................................There are "So Many Things", that can Cause, Engine Running Problems, such as the One, that You are having, and, Depending on, just, "How Many Gadgets" and such, that Your particular Motorhome, has "On It", pretty much related, to Your Engine's..."Electrical and Fuel System"..."Design"...so to speak, makes for, Others, and Myself, that "Fix", these Types of Engines, and what makes them Go, to, Really be aware of..."Exactly"..."What, Parts and Pieces"...were..."Actually On/In the Vehicle"...at the time, when, Working On It/Fixing It, as that my Friend, will make, a "Very Big/Huge Difference", on just how, a certain Vehicle gets, shall we say "Cured", so it will Run...Really Well, with lots of Performance, and when going easy on the Gas Pedal, some pretty darn good Fuel Economy as well (hopefully, that is...lol)..............................Oh Yeah, before I go (depart), does Your Engine's "Air Cleaner Housing", have a rather Large..."Rectangular Shaped Box"..."Mounted On It"...???...if so, Your Engine is probably Equipped with a..."Lean Burn System"...where the Fun, really starts to Begin...!!!...Yikes...!!!...lol.....................................So then, if You can Find, and tell me, What those...."4 Numbers, followed by the Letter "S"...that I hope, You can See/Find, Stamped Into Your Thermoquad Carburetor, then, I should have a much better chance, at narrowing down, what-ever-it-is, that's causing..."All-of-this-Commotion"...!!!...lol............................Well........Till next time..............Be Safe, take care, and have a good one.
RockysRoadshow Hi Rocky, thanks for your reply from Canada Eh ! lol , well my carb number is 9275 S , it has the vacuum curb idle solenoid thing instead of the electrical one . I have the carb on the bench at the moment as I wanted to test the EGR valve too which seems to check out fine, holding down when I block the pipe and closing when I release the vac. I have the vacuum amplifier on the vehicle too , not sure if this is working properly , are you aware of any test that can be done on this ? I am going to strip down the carb today to give it a good clean out, blow done the jet holes etc etc. don't have a service kit so will have to go with a good clean out and check over. One thing I did notice when it was running a couple of days ago was there was no movement on the secondary venturi doors when I gave it some extra throttle. The mechanism is all working correctly on the bench, the primary circular doors on the bottom open ok and the secondary doors open ok when the tang comes around and hits on the mechanism when giving it more throttle, but as I recall the venturi doors did not open or even move, I know this is for when giving more throttle but I'm not sure what operated these doors, is it vacuum ? I have found a great tech sheet online which shows the correct path and fitting for all of the vacuum lines so I can test all of them and make sure they are on the correct ports etc. As for when the problem occurred, we bought her last October and drove her back some 300 miles , she had a little cut out just after leaving the guys house when going to get fuel, she did it a couple of times , just stalled out at the red light but started straight back up with no problems. we stayed overnight and then drove back the next day taking our time and she drove back at a steady 60 MPH without any problems. We took her out twice over the next 3 - 4 weeks and a couple of times she did cut out and one time took a little bit of starting again, with a little bit of misfiring and struggle . On the way home that day I had to keep knocking her into neutral when in traffic because she was stumbling. Other than that she drove home ok. She had been sitting over winter due to my ill health at the time so didn't get used apart from starting her up now and again. When I took her for her first run to get the MOT on her (government test) she started lovely, ran well til we got to the test station about 20 mins drive, she then just kept cutting out as soon as the test guy put her into drive. He eventually cancelled the test and we tried to drive home, she felt like she was running on only half the cylinders sometimes and would not go into drive at all without stalling out.She struggled to start at all for a while, misfiring running on only a couple of cylinders and one time giving off a huge backfire through the exhaust This lasted for quite a while until I took off the cover and tried to see what it could be. I cleaned up the distributor cap points and the electronic pick up points etc, the coil seemed to be very hot, more than usual, so cooled it down a little, she then started up after a couple of attempts and drove all the way home again without any fuss until we reached our house and she cut out again, started up straight away and she has been on the drive ever since. What I did with cleanng contacts etc could have been pure coincidence as we had been stopped for a good 30 mins and she could have cooled down enough on her own. I know it is really difficult to try and diagnose without seeing the engine and problems in the flesh so to speak but you are the only person on the net I have come across who has such in depth knowledge of this carb and its workings I thought it way have been something you had come across before. I don't have that box on the air cleaner you mentioned, just a straight forward air cleaner with attachment for a large breather hose and a small hose which goes to some screw in unit on the manifold which is plugged blank on one side and has a heavy metal pipe with a union going off to the front somewhere, and a heavy breather heading back along the top of the transmission tunnel to where I'm not sure yet. The vacuum choke pull off is working ok and the choke comes all the way off with the plates standing straight up in the air. The elctrics system is the electronic pointless distributor with the reluctor and pick up plate, with vacuum advance. I have replaced the coil with the correct unit and also the ballast resistor. I will change out all the HT leads too but I'm pretty sure although as I say inexperienced with this carb set up, that it is fuel starvation or vacuum problems, I am going to go get some vacuum hose today to change out any that's looks busted or cracked, having said that, they all still look very flexible and soft and not looking too worse for wear from heat damage etc. I think that's all the extra info you needed at present but if theres any more needed I will be only too happy to pester you and twist your brain with my problems lol , all joking aside your help is really appreciated from so far away from the man who I will come to name the Thermo Quad Specialist, many thanks Rocky, Colin
Bulldogcol Greetings Bulldogcol....Thanks, for providing, the much needed Information, that, will really help me, try to figure out, Your Engine's, tendency, to Stall at Idle Speed, when You put the Transmission in Gear/Drive......................First, I gotta Warn You, about "Re-Assembling" Your Thermoquad Carburetor, and, "Not Using New Gaskets", and the Other Parts, that are in a/the, Thermoquad Carb Rebuild Kit...............................There is a good and strong Possibility, that, by "Re-Assembling" Your Thermoquad Carb, "Using, the Old, Dried-Up, and, Already Squished, "Gaskets"...that, an "Air Vacuum Leak, and/or, a Fuel Passage Leak"...could materialize, which, could result in, an even "Bigger Back-Fire", due to, More Air, and Less Fuel, Making its way, into Your Engine, via Your Engine's Intake Manifold...!!!..................................The Accelerator "Pump's Plunger/Piston", is very Important, so Your Engine "Does Not Fall on its Face", and Hesitate, while doing just about any "Acceleration", more-so, from a standing start.............................The Needles and Seats (2 sets for a Thermoquad), are Needed, so, Your Thermoquad, Does Not "Start Flooding", and/or, causing Too Rich of an Air/Fuel Ratio/Mixture for Your Engine, at any given time.............................If Your Thermoquad, has those 2 "Nitrophyl" (looks like black plastic) "Floats", (inside it), and, if they start "Acting like a Sponge"...then, an "Overly Rich Air/Fuel Ratio/Mixture, it will be...!!!.................................If You want to do it right, and to have the best chance, at not creating any Un-Needed Headaches, by trying to save a few "Pounds" (Your Currency?), or Dollars, for that matter, then, as I see it, You'll be wasting Your time, and, more then likely, creating, even more, Engine Running Problems, that You have now...Yikes...!!!...lol..............................Here's what I would do, if I was the Proud Owner, of Your Motor-home......................................Purchase a "Rebuild Kit", for the Exact...9275-S...( I hope I got it right?) Thermoquad Carburetor...along with.."2 New Floats"...a "New Choke Pull-Off"...and that, quite Thick..."Gasket"...that goes Between, the Bottom of the Thermoquad carb, and the Intake Manifold (always remember, that, "New Gaskets"..."Prevent"...both..."Vacuum/Air Leaks"...as well as...Carburetor, Joint related..."Fuel Passage Leaks"...!!!)..................................I would do a..."Complete Ignition System"..."Tune-Up"...which Includes New Spark Plugs...and the Electrodes "Set", at the "Specified" spark plug..."Gap"..................................If the Distributor Cap & the Rotor, looked questionable, to me at all, then..."New Ones", it will be..................................If the Spark Plug "Leads/Wires', were old, or had lots of Miles/Kilometers on "Them", they would get "Replaced with a New, Correct Set"........................Once, all of the Ignition System Parts and Pieces, were replaced, as need be, then, I would "Check the Ignition"..."Timing"...and Adjust if Needed, to the "Correct...Setting/Specifications".......... Now then, about, how You were sayin', that, Your "Ignition Coil", was..."Too Hot"...while in Operation..................................I'm thinkin'...that, Your Ignition Coil is Mounted Horizontally, and, I actually had an Ignition Coil, start to "Leak Oil", as I found out, when I removed the High Tension Lead (looks, just like a short, spark plug wire), from the Ignition Coil's, Center, High Voltage, "Tower", and, I'm thinkin', if Too Much Oil Leaks out, that, as I see, just might result in, an Oil Filled Ignition Coil, possibly, starting to "Over-Heat"...maybe....................................Make Sure, that, Your..."Ignition Coil"...and, the..."Ballast Resistor" (2 or 4 Terminals?...and looks, kinda like, whitish colored Porcelain)..."ARE"...the "Exact"..."Specified Ones"...having the "Correct Part Numbers" on "Them", for Your..."Exact"..."Engine & Vehicle"...or, some Problems, may be the result..................................Your Engine "Stalling", at Idle Speed, while placing the Transmission, in Gear/Drive, could be...one or both...Ignition System"...related...and/or...."Fuel System"...related...as I see it, and also, from, all of the previous experience, that I've had the pleasure to entertain...head scratch...and, try to figure out, and, in the end, I Won, and, had great running engines, as a result of, what I had to do, to...make "it" happen...!!!...lol..........................If Your Ignition System, and, Fuel System, that includes Your Thermoquad, are Functioning, at a "Good Enough Level", then, all it might take, to keep Your Engine from Stalling, or almost Stalling, when You put it in Gear, might just be a matter of Adjusting the "Curb Idle Speed Screw or Solenoid", to Increase the Idle Speed, up to the "Specified Idle Speed", for Your "Exact, Engine/Vehicle Combination"...and/or...maybe the Thermoquad's "Idle Mixture Screws"..."Set To"...the..."Factory Specified Settings"...in order to produce, a..."Smooth Enough Idle"...and not Waste Gasoline, by being Set..."Too Rich"...at the very same time...hopefully...............................If You plan on making any Adjustments to Your Thermoquad carburetor, I find, that, by making any "Idle Speed"...or..."Idle Mixture"...Settings/Adjustments...while having the Engine Running, is to, have, for..."Safety's Sake"...the Automatic Transmission's, Gear Selector, Placed in..."PARK"...on Level Ground, and some Wheel Chalks/Tire Stoppers, so the vehicle..."Does Not Take off"...and cause any Serious Problems...!!!...................................Also, Make Sure, that, there is "Plenty of Fresh Air and Ventilation", when-ever the Engine is Running, as..."Exhaust Gas is DEADLY"...!!!.................................................................................When it comes to having, a Well & Properly Running Engine, both Performance-wise, as well as Economy-wise, it will usually require, that, a considerable amount of Money be Spent, for the much needed Parts & Pieces, that the Engine, and, any related parts, that "Make it Go"...or...Spare the Money...and Buy...Lots of Headache Pills...cuz...You'll probably..."Need-Em"...when You Engine, Finally...Quits Runnin'...in, the..."Middle of No-Where"...Yikes...!!!...lol................................Well, there You have it, for now that is, and....................Till next time.............Be Safe, take care, and have a good one.
RockysRoadshow Thank you once again Rocky, I shall take your advice and order a rebuild kit for my model carb, I found a company who had my listing in stock in the states $45.00. I shall also order a new contact pick up assembly for the distributor plus a new cap and a set of HT leads inc coil lead. Hopefully at some stage the fault will be cured by changing out everything. I shall keep you advised of the updates and hopefully once day soon will be able to say to you, yes she is fixed and on the road again running superb. In the meantime I will get on with it and be back to pester you if any more advice is needed,Cheers
Rocky, Great videos, thanks much - you really know your stuff and I like that! 4 comments: 1) Do you have a vid on how to tune the accelerator pump, I dont seem to see that one, 2) my mixture screws are now 4 turns out and definitely better than 3 turns, is that OK? and 3) my idle does waver a bit and wonder if you can guess why that is, and 4) how the heck where and how - do I put a air cleaner mounting stud to keep the air cleaner from flopping all over the place! thnx, John
...when you tap the gas pedal, the fast idle screw drops to the second step of the fast idle cam, thus, lowering the RPMs (Revolutions Per Minute) of your engine, when its running....Now for "Hot" Engine Starting = Hold gas pedal about 1/4 to 1/2 way down as you engage the starter (all cars are a bit different from one another, just apply the amount that give the best result), as soon as engine starts, release the gas pedal, so the engine will idle on its own....(con't)...
Could you help me. our thermo quad caught fire in our rv i got rebuild kit but before and after cleaning I realized the valves don’t open? I tried Ed 40 and nothing
Greetings...Linda Burkett.........Thanks for watching.........Better late, than never, I guess (me, that is).........You have probably got it fixed by now, but, I'll still put in my 2-cents worth, never-the-less..........Carb fire...got really hot...bottom and top are made out of aluminum, which melts (and warps), at a lower temperature than steel or iron........Might be, that the throttle shaft/s seized, where it goes through/into, the TQ's throttle body (base plate), or maybe, the linkages got all distorted or whatever perhaps.........If you care to, you can let me know, what the conclusion was, to your mishap, and what the cure, ended up being, thanks.....and.....till next time......Be Safe, take care, and have a good one.
Hi Rocky. Following up from my previous problems. it turned out to be the electronic contact unit in the distributor that was causing my hot die out problems. Anyhoo your help on the thermo quad was superb and I now have a rebuild kit as you suggested, I was having a problem on our last run out with massive fuel consumption and after watching your videos again a couple of days ago I have figured out a major problem is the secondary air doors are not open, I have ordered a new choke pull off which hopefully I will get in the next week or so from the states. I need to ask one question though if I may, how do you set up the fast idle correctly, my choke wasn't coming off fully which would contribute to the fuel consumption along with the none opening air doors, I want to rebuild the carb and also set it up spot on so to maximise fuel consumption because she is using so much it is actually limiting our use of our RV because we cannot afford her getting just ten mpg, I'm sure a rebuild and full set up with the secondary doors opening will almost double our gas mileage. I have watched and read a couple of blogs where people talk about the "special" noise from the carb when the secondary air doors are drawing in, I haven't heard this noise yet but look forward to it. Could you point me in the direction of your video that deals with the setting up of the choke fast idle please or is it a simple question of making sure it goes onto the bottom step when the choke is fully off. Thanks again Rocky and hope you're ok ovet there in Canada ☺
+Colin Gowland Greetings Colin Gowland....Good to hear, that You found out, what the problem was, with Your Distributor..................If...???... it is the Reluctor (has those teeth on it, that spins with Your distributor's shaft), and is very Close to, that Magnetic Pick-up Unit, I hope that, You "Set that (air) Gap", to "Specifications", with a "Brass or Non-Magnetic", type of Feeler Gauge", cuz, if that "Gap", is Too Big or Too Small, Your Engine, might not Work, as good as it should be, and maybe, might have some Ignition Miss-Firing, possibly.................................I hope that, if and when, You have, or, are going to, "Rebuild" Your Thermoquad, that You "DO", install, "2 Brand New Floats", Especially, if the ones, that, are/were, in there previously, are made of that "Nitrophyl" Material (looks, kinda like, black plastic)..............A while back, I had, one of those..."Nitrophyl Floats"...in a Thermoquad Carb..."Sinking"...as in Sunk, or partially Sunk, and, it kinda Acted, just like a Sponge does, as in, "it" Absorbed Gasoline, causing it to "Sink", and Didn't actuate the Needle, inside its Seat properly, which Allowed "Way Too Much Gasoline", into that particular "Float Bowl" (there are 2 of them), which causes, a "Way Too High, Wet Fuel level", and, the result was, "A Way Too Rich Air/Fuel Ratio"...for the Engine to Burn Properly, and, the Smell was Obnoxious, to say the least...!!!........................You can "Check", to see, some-what, for, proper Operation, of the "Choke Plate", on Top of the Thermoquad, and "Fast Idle Screw" (that be, the Big Heavy Screw, that makes contact, with those Steps, on the fast idle Lever/cam), and the Linkage, that actuates them, by doing the following.....................With Your Engine "Cold and Not Running", Remove the Air Cleaner Housing's "Lid" just simply, pull down, easy now, on that "BIG Fast Idle Screw", and when it hits Bottom, make sure, that the Small "Tip", of that BIG Fast Idle Screw, is in that "Notch", at the Bottom, of all of those "Steps, on the Fast Idle Lever/Cam", and "Wiggles Freely", up and down, just a small amount, without making any Contact/Interference, with that very same, Fast Idle Lever/Cam, and, make sure, that, the "Choke Plate", is Fully "Vertical", while You are holding, that BIG Fast Idle Screw Down, at the same time..............................Sometimes, the Choke, and/or Linkage, gets Sticky or Stuck, so, make sure, that, it's all "Wiggly and Free" from hangin' up...............................Well, when that Secondary "Air Door", Opens Up, as far as it's able to", and You are able to hear, that, very impressive "Growl", that's not Fuel Economy, that You'll be hearin', it'll be the "Mad Rush of Gasoline"...(and the Air, required, to go with it, in the order of, an Air/Fuel Ratio/Mixture, of approx. 12.5 to 1, as opposed to just cruzin' along, be-in, at the 14.7 to 1 Air/Fuel Ratio/Mixture, there-abouts)...............Also, if the Factory/Stock, Sheet Metal, Air Filter..."Housing", is installed on the Engine, it will usually "Muffle" that "Growl-ee Sound", that Ur dyin' to hear, by quite a bit, as in, a reduction of Decibel/Loudness, as opposed to, the much Louder Growl-ee Sound, that Others will be Hearin', while having, something like, a rather Open/Un-Obstucted/Un-Restricted, Air Filter Unit, on Their..."I Wanna Hear it Roar, and I Wanna Hear it Roar Now"...Thermoquad equipped Engine!!!...lol...............................................The "Instructions" (sheet/s of paper), that are usually included, in the Rebuild Kit, should give You, a pretty good Understanding, of what needs to be done, as it applies, to the Rebuilding, and Setting-up, of Your Thermoquad Carb...........You have to..."Make Sure"...that You..."Follow the Sequence"...as in the..."Order of Setting-up the Linkages and Adjustments"...on Your Thermoquad Carb, according to, the (usually), Numbered Pictures, and what You Read in Print, on the Rebuild Kit's, "Instruction Sheet/s", that, as I've found, that will Show You..."How to Do It Correctly"...or, just like tryin' to Assemble "IKEA Furniture", and not doing it right, You'll probably, have to go back, and "Read the Instructions anyways"...!!!...lol...Not to worry though, it's usually a Guy Thing, where we usually..."Read the Instructions"..."LAST"...!!!...lol.................So, to Avoid..."Going on a Wild Goose Chase"...do Yourself a favor, and really study those "Instructions, that come with, the Rebuild Kit"...!!!................................Also, the "More %-age/Per cent-age", or Amount of "Ethanol/Alcohol" (if any, that is?), that is in the Gasoline "Blend", that You put in Ur Gas Tank, will usually, cause, the Non-Feed back, type of Thermoquad Carbs, to Supply the Engine, with a "Leaner Air/Fuel Ratio/Mixture, as compared to that good ole Gasoline, that Never had any Ethanol/Alcohol in it, and, if Ur Engine, starts to "Lean Surge" on Ya, while just Cruzin' along at City Speed, that Ethanol/Alcohol, might just be the Culprit, that's causin' it, perhaps.................Remember Now........Install..."2 New Floats" (if, there were those Nitrophyl/black plastic ones, in there previously).........and a New "Choke Pull-Off"...cuz, sometimes They Stick, or get too Slow, or, maybe even have an unwanted Air Leak, in its Diaphragm, perhaps..............................Sorry, but I don't have any actual Thermoquad Carb, "Adjustments/Set Up" Videos, at the moment....................I hope that, Your Fuel Pump, "Is Not" putting out, too Much Fuel "Pressure", cuz, the Floats, will not have enough Force, to apply to the Needles, to Stop, any Fuel Pressure, that's Above, oh, about 7 PSI/Pounds per Square Inch, or, put it this way, Fuel Pressure, Over 10 PSI, is, Way Too Much, just sayin' now..............................To have the best chance, at having Your Thermoquad, "Run/Perform, and with good Fuel Economy" as well, it's almost a no-brainer, well, for me that is, to have, all of those, very old/high mileage "Thermoquad Parts"..."Replaced with New Parts"...and also, be..."Set-up/Adjusted Properly"...as well, cuz, from my past experience, there's No Other Way...!!!...lol...................Let me know, when You get to the point, of actually "Rebuilding Your Thermoquad Carb", or, it'll probably, just end up, be-in, another one, of those..."Wild Goose Chases"...!!!...(and yes, I know all about..."Them"...!!!...lol).......................Well, things, here in Canada, are Eh-Oh-Kay...Thanks, and, I hope, all is Well, with You, and Yours as well............and.........till next time...............Be Safe, take care, and have a good one.
@WindowsIP Might not be the Carburetor? To me it sounds more like a Vacuum Leak. Check vacuum hoses and what they connect to for Vacuum leaks. Intake Manifold Gaskets, and nuts/bolts tight? There are so many things that can cause your fluctuating idle. If it is Computer controlled, check for trouble codes. Check EGR Valve and connections. If Carburetor has lots of miles/kilometers on it, a carburetor rebuild may be what is needed. Try to get a good Book on your Carburetor, it should help.
Greetings...belloa3026......Thanks for watching......You asked, what would I do different, when it comes to lean burn........Well, it all depends upon, what you want it to end up as, as in, almost stock/factory, so it will have all of its factory parts and pieces, so it will pass a visual test at the smog testing station? (maybe)..........If the vehicle does not have to go through the smog test, and the area where you live, doesn't care how the vehicle is modified, then, there are, quite a few things that I would change alright.........I would get rid of the lean burn system altogether..........A different distributor, that has advance weights and springs, and a vacuum advance unit mounted onto it, so it will work, shall we say, the old school way........I would also get a basic looking thermoquad carburetor, much like the thermoquad, that you see in my youtube videos, that does not have all of those extra parts and gadgets, showing on the outside of the thermoquad carburetor, that way, it will be much easier to work on, and tune as well........I've never had, or worked on a lean burn system at all...........Do a search on youtube, for people that have done, the elimination of the lean burn system, in order to see, all of the work that needs to be done, if that's what you're really after, in the long run........You can still, just rebuild your lean burn thermoquad, by getting a rebuild kit for it, if you want to........If you do, then, buy 2 new "Brass" floats, as those black/nitrophyl floats, can at times, absorb gasoline, and start to sink, which will cause a rich (air/fuel ratio), running thermoquad.........Good luck with, what choice, you might make, and.....be safe, take care, and have a good one.
Now, about a leaking Thermoquad....If you notice lots of fumes coming from your exhaust systems tail-pipe (make sure you Never run an engine with the Garage Door CLOSED!!!), that could be one or both Seals inside your Thermoquad drying out and shrinking causing a leak...could also be one, or both Floats starting to Sink! (if they are the Plastic ones)...also if you notice any gasoline like smell on your Oil Dipstick when you check your oil level...Those are some possible "Tell-Tales!"...(con't)
Now, on to the Stud!...lol........It looks like my "Display" Thermoquad doesn't have an Air Cleaner Mounting Stud at all !!!........Oh my goodness !!!......Ok, here's the lowdown on the subject........Have a look at the secondary air door nearest the center of the carb (on top) and you will notice a square cut-out there........Down under is a Threaded hole that has a 1/4" - 20 T.P.I. or (One-Quarter Inch Diameter times 20 Threads per Inch tapped hole, I think...) Insert correct stud length!
Hey Rocky. I was wonder if you could help me with something. I have the 800 CFM thermoquad off of a 77' Chrysler Cordoba that I still own. I'm having a problem with gas evaporating out of the float bowls, which makes it hard to start. I'm not if there is a leak, or if it evaporates quick naturally. It only does it if you leave it sitting for more than four days or so. It always starts, but its a major inconvenience. Is there any way to test for a leak?
...Cold Engine Starting = Push on gas pedal and release...start car...when engine starts, it should be running at high RPM's...tap gas pedal, that should lower RPM's a bit so the engine doesn't star screaming at you!...lol...What that does is set your Choke valve (plate), and sets the fast idle screw on the highest step of the fast idle cam before you start cranking the engine... when engine starts, RPM's are a bit too fast...then...(con't)...
Bernardo Rangel Greetings Bernardo "Cricket" Rangel....Thanks for watching, and for Your comment (question) as well.................................It appears, to me, that, Your "Idle Mixture Screws" (those be, the 2 Idle Mixture Screws, found, in/on, the Lowest part, and, at the Front of Your Thermoquad Carburetor) are Working, just as "They" should be Working, in that, You are Hearing, Your 360 Engine's "RPM's (Revolutions Per Minute), going, both, "Higher", and "Lower", when-ever You happen to "Turn", one or both, "Idle Mixture Screws"..."In or Out" (In = Clockwise rotation...and...Out = Counter-Clockwise rotation), while the Engine is just at "Idle Speed"....................For the most part, as it pertains, to a Thermoquad Carburetor, while having the Engine, up to Operating Temperature, and at..."Idle Speed"...then, Turning, one or both..."Idle Mixture Screws"..."In/Clockwise"...will usually..."Lean-out", the "Idle Mixture" (or, Air/Fuel Ratio)..................................When Turning, one or both..."Idle Mixture Screws"..."Out/Counter-Clockwise"...then, the..."Idle Mixture" (and again, I say...or, Air/Fuel ratio...lol), will usually..."Richen" (as in, Make Richer), the..."Idle Mixture" (or, Air/Fuel Ratio)..................................How, a Thermoquad's..."Idle Mixture Screws", actually "Get Set", as in, Full and Partial Turns, "Out", from, just being "Lightly Seated" (aka, Fully Turned...In/Clockwise...until they Stop), depends on, wether or not, the Vehicle in question, has to be..."Emissions Tested"...???................................I've used, what is called, the.."Lean Drop Method" as it pertains to, how I Adjusted both "Idle Mixture Screws", as well as the "Idle Speed Screw", to arrive at, an "Air/Fuel Ratio" (Mixture), that would, shall we say..."Lower/Reduce, the Emissions/Pollutants"...that were Exiting my Tail-Pipe, or, Tail-Pipes, as the case may be, and, be, Under the Maximum Allowable Emission Limits, as set forth, by, that, rather "Sensitive"..."Poice-Tracking-Dog-like"..."Computerized"..."Tail-Pipe-Sniffin'-Equipment"...at the..."Vehicle Emissions Testing Establishment"...that..."Just Can't be Fooled"...or, can "It"...???...lol...........................If, the Vehicle in question "Does Not" have to be "Emission Tested", then, it's, that much easier, to set-up, the "Idle Mixture Screws", and, the, "Idle Speed Screw" as well..............................Here's the Deal....................We Don't want those "Idle Mixture Screws"..."Set Too Rich" (as in, Out/Counter-Clockwise, from being Lightly Seated), as, by doing so, Gasoline gets Wasted, that the Engine, really Doesn't need, while just sitting there, Idling away.................................Also, we Don't want those "Idle Mixture Screws..."Set Too Lean" (as in, Turned In too much), or, that in itself, can at times, cause, what is known, as a "Lean Miss-Fire", where-by, the "Idle Mixture" (Air/Fuel Ratio), while, being "Set Too Lean", will at times, make for, an "Idle, Air/Fuel Mixture", that "Won't Burn Properly", and, cause the Engine to "Miss-Fire", and, all of that Gasoline, that Doesn't Burn, some-what, Completely, gets sent, out of the Engine's Exhaust Valve, and through the exhaust system it goes.......................................If the Vehicle "Does Not", have to be Emissions tested, then, here's a rather simple, and Basic way/method, that, I, in the past, use to do/perform, on an Engine, that had a Carburetor, that Did-Not, have any Smog-Gadgets, mounted on it...............................Before "Starting the Engine", Make Sure, that, there is Plenty of "Fresh Air and Ventilation", as "Engine Exhaust Fumes are Deadly"...!!!........................Get the Engine, Fully Warmed Up, and make sure, that, the Choke is Fully Off as well................................Shut the Engine Off, then Hook-up a Tach (aka, Tachometer), then, Lightly Seat, the Idle Mixture Screw/s, and Place a "Chalk-Mark", on "Them", closest to the Sky (12-Oh-Clock position)...then turn them Out, oh, about 4 Turns, then, Start the Engine.....................................Lettuce say, for Example (Only!), that this Hypothetical/Vehicle had an Automatic Transmission, and, that, the predetermined/hypothetical..."Final"...."Idle Speed", was "600 RPM", with the Automatic Transmission In Gear, and my Foot is on the Brake! (as in, when I'm all Finished, said, and done)................................I would make my Adjustments, while the Automatic Transmission was in "PARK", for Safety Reasons, and, have the Vehicle on Level Ground, with the Parking/Emergency Brake On, and also, while having some Bricks or Lumber, to Block the Tires, so the Vehicle...Doesn't go, on a "Trip" of its Own...!!!..................................I do my Hypothetical, "Idle Mixture" Settings, while the Automatic Transmission, is in "PARK", at "700 RPM's", because, when I'm Finished, all said, and done, and, when I finally get around to Placing the Automatic Transmission in "GEAR", the "Idle SPEED", will usually, "Drop Down/Reduce", about "100 RPM's", give or take a bit, depending on the Engine be-in worked on ,............................Then, I would keep a close watch, on the Tach/Tachometer, when the Engine was running, and, any time, that I was Adjusting, the "Idle Mixture Screw/s", I would Make Sure, that, if and when-ever, the Engine "RPM's"...Went-Over, that..."700 RPM's"...I would "Re-Adjust", the..."Idle SPEED" Screw, back to that "700 RPM's", with the..."Idle SPEED Screw Only"...!!!................................You see my Friend, and, as You have probably already noticed, is that, when-ever Turning the "Idle Mixture Screws", with the Engine Running, the Engine's "RPM's", will usually Change, with at least One Exception, and that Exception is...........................When an Idle Mixture Screw, reaches "its", shall we say "Rich Limit", kinda like, when "Turning Out" (One Only), "Idle Mixture Screw", there is usually, a point/setting, where-by..."Richening/Turning-Out"...the..."Idle Mixture Screw"...Any..."Richer/Out"..."Does Not", seem to Change the Engine RPM's much, or, not all all, and, that to me, is, probably, just, like I was sayin' earlier..."Just a Waste of Gasoline"...!!!...lol...but, then again, that "Rich Limit", well, once You hit it, that is, is "Still a bit on the Rich Side", and, is still, for the most part...."Wasting"...that..."Liquid Gold"...!!! (aka, Gasoline)..................................What I'm really after here, is, tying to get, the Idle Mixture Screws, "Set", about the "Same Amount", of, "Turns and Partial Turns" out, from being Lightly Seated, in order to, shall we say, have them both "Set", so that they are some-what "Balanced", to, One-Another...rather then having, One Set, Out Too Far, and the Other One, In Too Far (as an example).............................I Adjust the "Idle Mixture Screws", so, the Engine, "Idles Fastest", while keeping the Engine RPM's at that, in this case...700 RPM's", with the "Idle SPEED Screw", cuz,, if I Don't, the Idle Mixture, is probably, gonna be "All Messed Up"..................................You can use a Tachometer, or, a Vacuum Gauge (to get Highest Vacuum reading), and, I've even got pretty good results, just Use-in my Ears/Hearing, while Setting, both, Idle Mixture Screws, as well as, the Idle Speed/Screw.................................Just make sure, when, all's said and done, is to..."Not have the Engine's "Idle Speed Too Fast, in Park, or In Gear"...!!!...as, if the Idle Speed is..."Too Fast"...and, You go from "Park, to In-Gear"...then it usually goes "KLUNK", Big Time, when You do so...!!!...and...once, In-Gear, the Vehicle, will usually..."CREEP"...as in..."Move on its very Own, and probably, Too Fast as well"...and..."Your Foot Was Not On the Gas Pedal"...at all...!!! (to lol, or, not to lol, that is the question)...................................Yeah, I know, that, it may seem to be a bit Tricky at first, but, with a bit more time spent, just as I have, You'll know what to expect, some-what, as to, what's go-in on, when making some Adjustments, from time to time.............................Just, keep in mind, that, "Gasoline, Internal Combustion Engines"...tend, to Get..."Zero"...Miles per Gallon...when...the..."Engine is Running"...and...the..."Vehicle"..."IS NOT MOVING"...!!!...lol................................So, that's about it for now, and...................Till next time.................Be Safe, take care, and have a good one.
left is richer, right is leaner. Most all ThermoQuad have a high and curb idle speed screw. Fast idle is the long screw on top, curb idle on bottom. the fast idle cam often wears out. if it works, set fast idle at 1200. curb idle should barely touch the throttle plate link. if the motor won't run unless curb idle screw is in, advance the timing and/or adjust mixture so it will idle with little or no added idle air.
+Pete Kranz ....Greetings Pete Kranz....Thanks for watching.................There are a number of things to consider, and to be aware of, when it comes to a Thermoquad Carb equipped, factory/stock, engine and vehicle, and it gets kinda Fussy, when that Thermoquad Carb, has to make it though, Smog/Emissions Testing (just ask me, cuz, the adjustments/setting-up, that I did in the past, worked really good, and I got some pretty impressive smog reports to prove it...lol)....................There are different Specifications, for different engine/vehicle combinations, for a Thermoquad's Fast Idle Speed Setting, such as, which Step, on the Fast Idle Cam/Stepped Lever, that the Fast Idle Screw should be on, as well as, whether the setting, is to be done, on a cold (bench setting?), or, hot engine as well........................As for the Factory's way of doing things, when dealing with a Stock/un-modified Engine, and having the Engine warmed up to Operating Temperature, the Primary Throttle Plates/Butterflies, at warmed-up, curb Idle Speed, should be Opened-up, just enough, to expose, the Transfer Slots, so there's, what appears to be, a Square Shaped Opening there-abouts, of the Transfer Slots showing, as viewed from the Bottom of the Thermoquad, in order to have the Thermoquad, Transition smoothly, and properly, from curb idle speed (idle circuit), up to where, the Primary Main Circuit (primary main fuel jets and metering rods) take over, and yes, with a little help from the accelerator pump as well...lol..............I went, and got hold of, my good ole Thermoquad, that You see in all of these videos, and I closed the primary throttle plates/butterflies 100%, and, there was..."No Transfer Slots Showing At All"...!!!...Yikes...!!!...lol........................Some Carburetors, do have a separate, and adjustable Idle Air Bypass Circuit or what-ever in them, and, even so, I would have a very close look at that Carb Manufacturer's Instructions/Specifications, to make sure that, the Primary, and/or Secondary Throttle Plates/Butterflies were in the "Correct Position" in relation to the Transfer Slots.............Oh, and, the Big Heavy, Fast Idle Screw, is on the Bottom, "Under" the Curb Idle Screw (I had to look, to make sure...lol)...................Then, if the Thermoquad has a Curb Idle speed "Solenoid" on it, mounted on the opposite side, in relation to where the Big Fast Idle screw, and that, so called curb idle screw is located, well, that "Solenoid", is for Setting the Warm Engine, Curb Idle Speed, and that Screw, that we were just calling, the Curb Idle speed Screw, that's just Above, that Big Heavy fast idle screw, would usually be set, oh, about 100 RPM's (that be-in a Specification, that I might recall), Lower than, the Curb Idle speed "Solenoid" was set at, when at, the proper, warm engine, curb idle speed, in order to Prevent the Engine from Dieseling/Running-On, when the Engine was shut off, how about that...lol......................Now then, let's talk, a little, about Ignition Timing, as it applies to, a Distributor, that has centrifugal advance weights & springs, along with a Vacuum Advance Canister/unit on it as well, shall we.......You were saying, to Advance the Distributor's Initial (base) Ignition Timing, from, where it was already set at......................Well, there's a lot more to Ignition Timing, than You might think.................Sure, by Advancing the Distributor's Initial (base) Ignition Timing, at Idle Speed, it's pretty much a given, that, the Engine RPM's will Increase, to a point, alright...But...be Aware, by doing so, that, every other part of the Ignition Timing Curve, will Advance also, why is that Important You ask...???...well, let's say for example, that the Distributor's Initial (base) Ignition Timing has a Specification of 5...Degrees BTDC/Before Top Dead Center (crankshaft degrees), and that's a typical Smog Setting, oh, and, the Advance Canister/unit, is hooked up to a Ported Vacuum source, just so You know (cuz, it needs to be, for smog testing, in this example), and let's say, You went ahead, and Added another 10 (crankshaft) Degrees to it, to get that really nice Idle, now we're at 15 (crankshaft) Degrees BTDC....................Now then, the Total (that's the Initial/base degrees, added to the centrifugal/weights degree amount) Ignition Advance (please note, that Total, "does not" include the vacuum advance, and it was probably the racing crowd, that never used vacuum advance, that used that Total, description word, as my best guess), was already at the "Maximum" Total Ignition Advance, of, oh, let's say it's 35 (crankshaft) Degrees BTDC, shall we..................So, now, we just Added, that very same, Extra, 10 (crankshaft) Degrees BTDC, to that already Maximum Total of 35 (crankshaft) Degrees BTDC, and now we have a Total of 45 (crankshaft) Degrees BTDC, and the Gas Pedal gets Stomped-On, and, is now at WOT/Wide Open Throttle...then, all of a sudden, the Engine goes...knock...Knock...KNOCK...BANG...BOOM...!!!...then silence, as the car, starts to lose speed, and onto the side of the road...it gets parked.......................The Most Important and Critical Ignition Timing Advance (crankshaft) Degrees BTDC Amount, as I see it, is when the Engine is going WOT/Wide Open Throttle, and also, when there is, a High Engine Load involved as well, cuz, that's usually where the Most Engine Damage will occur, and in a very short time-frame as well.........................So, it's kinda like that good ole sayin', and that sayin' is..."Look Before You Leap"...and in this case, I'm referring to, having a Plan First, and make sure that, the Ignition Timing Advance Curve, is "Safe" for the Engine, under All Operating Conditions, or a Person, might have Expensive Engine Damage, by not doing Their Homework First...........It's pretty much, a Whole New Ball-Game, when-ever an Engine gets Modified, and much more so, when that Engine's, New, Go-Fast Parts, start to fall in the category of..."Extreme"...!!!...Yikes...!!!...lol.........So, to play it Safe, go easy on the Ignition Timing Curve, especially on the Total (crankshaft) Degrees BTDC at WOT/Wide Open Throttle, or, maybe, bye Bye Engine, and, I sure hope not, and........till next time......Be (Ignition Timing) Safe, take care, and have a good one.
You add crank timing to base timing to get total timing, and most LA blocks ran best around 33 - 35° all in. Adding vacuum to that, and you should be 48 -58° total mechanical and vacuum all in (depends on distributor or ESC computer). The problem with tuning a TQ is whether or not you have the right jets and rods for your carb and application. I've had a few where the rods didn't match, or it was a "360" carb with 318 rods and jets. Then the floats leak, the bowls leak, transfer tubes leak, accelerator pump cup leaks, or I've even found the check ball missing.
+Pete Kranz ....Greetings Pete Kranz....I hear Ya, when it comes to, what seems like, a Lot of Ignition Timing Advance, when the Vacuum Advance, from the Vacuum Advance Canister/Unit (in crankshaft) Degrees BTDC, is Added to, the Total (Initial plus Centrifugal/Weights & Springs)...and...(in this Example, Total = 35 (crankshaft) Degrees BTDC ,for a Factory Stock, Low Compression, V-8 Engine, so, we would almost be guaranteed, a nice Strong amount of Manifold Vacuum)...........................A Factory installed, Vacuum Canister/Unit, for this particular Distributor, would usually have, a Pre-Set, Amount of Vacuum Advance built into it, so, when it was Maxed-Out, and Added to the Total (Initial and Centrifugal/Weights), then, we should arrive at that "Magic" Number, would we not...???.....................As You were saying, up to 58 Degrees, but, for me, that seems a bit on the high side, but, with a functioning EGR/Exhaust Gas Recirculation System, Diluting, an already Lean Air/Fuel Ratio/Mixture, it could be possible, due to a very Lean Air/Fuel Ratio/Mixture, needing, so much more Ignition Timing Advance, to arrive at, what the Engine needs, while under a Light Engine Load, to have the Peak Cylinder Pressure occur, at about 15 (crankshaft) Degrees "ATDC/After Top Dead Center", to get that, good ole, Good/high as possible Gas Mileage, which ultimately, reduces the Gasoline Bill...but only if, You or I, can keep the Go-Fast Pedal, Off of the Floor...!!!...lol.............Unleaded Gasoline, with about 10% Ethanol in its Blend, as I've experienced, with a Thermoquad Carb of mine, tends to Lean-Out the Air/Fuel Ratio quite a bit, and I had to Re-Jet (Enlarge), a TQ's Primary Fuel Jets, from Ninety-Five Thousandths of an Inch, all the way Up-To, One Hundred (and) Four Thousandths of an Inch, just to get rid of, that very annoying Lean-Surge (Car was Bucking back and forth), while just maintaining city speed, that I was havin' a few years ago.....................Gotta remember, that, this particular TQ was Calibrated on the good ole Gasoline of the early 1970's, that never did have any Ethanol/Alcohol in it what-so-ever.........................I actually have a UA-cam Video, on how I Enlarged those two TQ Primary (fuel Jets), along with a Tapered Gauge, that I made out of, a piece of coat hanger wire, and used a felt pen and a micrometer to measure the hole/orifice size of the Jet, that was showing up on the Gauge, of those two measured, Enlarged Primary Jets......................Also, in this very same TQ, I put some Truck Metering Rods in it, (2024's if I recall correctly), where-by, the Large Diameter was super close, the Taper was reasonably the same, but the Power Tip Diameter was Three Thousandths of an Inch Smaller than the Original ones, and, the result was Super, but one more thing to make it Super-Duper (lol), that I did, was, I made up a Custom, Choke Pull-Off linkage "Rod", that actuates the Choke "Only", and now, has nothing to do with Controlling the Secondary Air Door/Valve at all...................Only the Torsional Wind-Up Spring (was set at the Factory Specification, of, 1 and 1/4 Turns), Regulates the Opening of the Secondary Air Door, and Man, once the engine is at operating temperature, it Goes Like..."!#%&*%#!*#...and then some...!!!...and never hesitates, bogs, etc............This awesome Mod that I did, was on a TQ equipped, small block Dodge, 4 Speed "Standard" Transmission/with a Clutch, so, I can't say, whether or not, it would be as Awesome, or even work for that matter, if done to a TQ, that was on an Automatic Transmission Car...???.......................The only real problem I had with Nitrophyl (looks like black plastic) Floats, was when one of them, decided to become a Sponge, and absorbed Gasoline, and started to Sink, as, I found out, while having, what seemed to be, a Choke related Engine problem...............Yes-Sir-ee-Bob, when I looked down, into the TQ's, passenger side, primary throttle bore, while the warmed-up Engine, was running at idle speed, there it was, the Primary Nozzle, was goin'...Drip...Drip...Drip..........No More, I wanna Be a "Sponge", Nitrophyl Floats for this Kid...Only Brass Will Do from Now On...!!!...lol.......................Have You Seen that 4-Barrel Street Demon Carburetor, that came out, just a few Years ago...???............They sure have, what looks to be, lots of TQ Features on it/them alright..................Can even get one, with that good ole black/plastic lookin', center section on it, that, as they say, should keep the Gasoline, about 20 degrees Cooler, that an all metal carb.................I might just get me one, some day.......................Well, that's about all for now, and..........till next time..........Be Safe, take care, and have a good one.
Greetings Dutch....Try this first...Start your Cordoba "1" Day after it was running last....Your Cordoba should start much quicker, providing that your Starter and Battery are performing at their best....Listen to how fast the engine "Cranks" over, and count how many seconds the starter is operating before the engine is actually running on its own...and, are you using the "Correct" Procedure to start your Cordoba, as per your Car Owners Manual?....(con't)...
...Now, about Gasoline....Gasoline, as compared to the Gasoline of the 1970s is about 3% "Leaner" then it was back then...Just that alone can cause any Carburetor to run a bit on the Lean side (Air-Fuel Ratio), when considering that the Carburetors back then were "Calibrated" using the Good Old Stuff! (Gasoline), and yes, the longer you let your Cordoba's Engine sit, without running, the less fuel there will be in the float bowls, due to Evaporation (and maybe leaks too!)...Take care, my Friend
You're welcome my Friend......It's nice to know that folks still use, and tinker with this old technology......I find that I actually have fun working on Carburetors, as opposed to working on fuel injection with all of that computer, sensor, and actuator kind of stuff......You can usually repair or modify the old school stuff, as opposed to just locate, and replace the faulty parts on the newer fuel injection stuff!
Greetings.....A good place to start in accelerating pump setting/s is to get a hold of the "Spec-Sheet" that you get when you buy a rebuild kit, or factory manual, as there are a multitude of different settings for each Carb/Vehicle/Transmission Application/s........I recall on one of the "4-Speed Manual Transmission" carbs that I worked on had 2 settings that I had to adjust for!!!..........As for your Wavering Idle speed......Sounds like a Vacuum leak or a plugged idle passage perhaps?
Rocky, your videos are very informative and I'm learning a lot about a carb I had previously never heard of. I am in the UK and have a 79 Dodge Sportsman motorhome with a small block 360 motor with a carter thermo quad carb. She runs great for about 30 mins or so then when at hot she will just stumble and die when I put her into drive. New pump fitted today along with filter inline , still the same, could you possibly point me in the right direction, we just want our baby back on the road again lol, thanks
Bulldogcol Greetings Bulldogcol....Thanks for watching, from across the "Pond" (aka, the Atlantic Ocean), b-cuz, I'm over here in Canada eh...lol).................................Now then, You did say, that, You wanted Your "Baby" back on the Road, did You not...???...well...did You remember to "Burp" Her, after She was "Fed"...???...as it might just be, Trapped "Gas"...!!!...lol..................................Lettuce now, get into some "Real-ism", and see if we can get Your "Baby"(that be-in Your 1979 Sportsman Motorhome, that is)...back on the Road....................First thing first...................Have a look-see, for the usually..."4 Numbers, followed by the Letter "S", that You should Find..."Stamped into"...Your Carter Thermoquad Carburetor's..."Throttle Body" (aka, the Lowest, Aluminum/Aluminium, Part, of Your Thermoquad Carb), on the (lowest part), at the "Left Rear", of Your Thermoquad Carburetor, and, once You find those "4 Numbers, followed by the Letter "S" (Hopefully, that is), then, please let me know, what "They" happen to be, if You are able to See "Them", as by doing so, I'll then, have a much better chance, as to just which "Model" of Thermoquad, along with the Addition, or, lack there-of, of any, and all, "Gadgets", that might very well, have be Added Onto, Your particular Thermoquad Carb, over and above, that, of what You "Saw", on my Thermoquad Carburetor, that I used, as a "Movie Prop", in this UA-cam Video of mine, which my Friend, is about as "Basic & Simple", as "They" can be...................................I'll now, give You, a "Few Things", that, can cause, like You were sayin', Your Engine, wanting to Stumble and Die, as in, having the Engine, Stall/Stop Running, once "it" (Your Engine) was Hot....................................Also, this problem, of having Your Engine Stumble/Die, when Hot, did You happen to Notice, if, it "Gradually got Worse", over, quite some Time, or, was it, one of those, "All of a Sudden/without Warning", type of, Problems, that just materialized...???....................................Might be a "Vacuum Leak", as in a Cracked, or (air) Leaking, Rubber, Vacuum Hose, or maybe, even, became Disconnected from its fitting/ connection point, or, quite rarely, a PCV (Positive Crankcase Ventilation) Valve, might get stuck Open, possibly...........................Might be, that Your "Choke Plate" (on top of Your Thermoquad, at the Front of it)..."Is Not Opening Fully/Vertical"....when the Engine is Up to...."Operating Temperature"...???............................If, Your Thermoquad Carb, happens to have, a Curb Idle Speed "Solenoid", that's usually Mounted on the Right Side (as Viewed, while You are sitting in the Drivers seat), at the Front of Your Thermoquad, either the Solenoid itself, is not working as it should, or the, Voltage/Electricity, is not making its way, to that very same Solenoid, which will cause, a Too Low, Curb Idle Speed, in most cases....................................."I've actually had, a PCV Valve, made out of, a Nylon/type of material, Separate into "2 Pieces", while I was Driving, and, when I stopped for a red light, the Engine ran horribly, and almost, Stalled/Quit...until I stuck it back together, made my way Home, and got a New One...!!!...lol..................................Another Time (same Engine), and also, while being Stopped, at a red light, the Engine started to Run, really rough, at Idle Speed, and, what "it" turned out to be, was, a small piece of "Swarf" (lol, maybe they use, or used that term, where You Live), to describe, that small piece of...Debris/Crud/ Yuck-ees...that, as I see/saw it, getting trapped, in my Thermoquad Carb's..."Idle (speed) Circuit/Passageway"...which I actually "Cured", by, Removing both, Idle Mixture Screws, and, by using a length of, good ole, 1/8 Inch/3 mm, inside diameter, Fish Aquarium, Neoprene, clear plastic Tubing, I took one end of it, and held it on, each of the screw-threaded Holes, that the Idle Mixture Screws came out of, and, I Huffed, and I Puffed...(using, good ole Lung Air Pressure, Via my Mouth), to try and Blow/Force, that, or those "Obstructions", that I was Thinkin', that, just might be causin', my Lumpy, Bump-ee, and not wanted, Bad Idling, Engine situation (at the time), and, I'll be Damned, that Huffin' and Puffin', that I did..."Fixed"...my Thermoquad's..."Plugged-Up"....Idle Circuit/Passageway, and, my Engine, was, oh so Happy, after I did so...!!!...lol...................................Now then, when was the "Last Time", that You had Your Baby's (Motorhome....lol), Engine..."Tuned-Up"...as well as, having all of the..."Parts and Pieces"..."Replaced"...as Indicated, in Your Motorhome's..."Owners Manual"...if indeed, You happen to have one, in..."Captivity"...that is (lol)...???....................................................................In order for me, to be able to actually, help You out, the best I can, I really have to know, just..."What"...???..."Ignition System" type...and, Any and All...."Pollution Gadgets/Devices"...both..."Electrically"...and..."Fuel System"..."Related"...are actually..."Installed"...in/on, Your Exact..."Baby/Motorhome"...as, at this particular point in time, I'm only pondering, a reasonable Guess, at, just "What"...???...might be "Included", in the way of, Parts and Pieces/Gadget-tree, that, actually "Make-Up", Your "Baby" (Your Motorhome, that is)...................................There are "So Many Things", that can Cause, Engine Running Problems, such as the One, that You are having, and, Depending on, just, "How Many Gadgets" and such, that Your particular Motorhome, has "On It", pretty much related, to Your Engine's..."Electrical and Fuel System"..."Design"...so to speak, makes for, Others, and Myself, that "Fix", these Types of Engines, and what makes them Go, to, Really be aware of..."Exactly"..."What, Parts and Pieces"...were..."Actually On/In the Vehicle"...at the time, when, Working On It/Fixing It, as that my Friend, will make, a "Very Big/Huge Difference", on just how, a certain Vehicle gets, shall we say "Cured", so it will Run...Really Well, with lots of Performance, and when going easy on the Gas Pedal, some pretty darn good Fuel Economy as well (hopefully, that is...lol)..............................Oh Yeah, before I go (depart), does Your Engine's "Air Cleaner Housing", have a rather Large..."Rectangular Shaped Box"..."Mounted On It"...???...if so, Your Engine is probably Equipped with a..."Lean Burn System"...where the Fun, really starts to Begin...!!!...Yikes...!!!...lol.....................................So then, if You can Find, and tell me, What those...."4 Numbers, followed by the Letter "S"...that I hope, You can See/Find, Stamped Into Your Thermoquad Carburetor, then, I should have a much better chance, at narrowing down, what-ever-it-is, that's causing..."All-of-this-Commotion"...!!!...lol............................Well........Till next time..............Be Safe, take care, and have a good one.
RockysRoadshow Hi Rocky, thanks for your reply from Canada Eh ! lol , well my carb number is 9275 S , it has the vacuum curb idle solenoid thing instead of the electrical one . I have the carb on the bench at the moment as I wanted to test the EGR valve too which seems to check out fine, holding down when I block the pipe and closing when I release the vac. I have the vacuum amplifier on the vehicle too , not sure if this is working properly , are you aware of any test that can be done on this ? I am going to strip down the carb today to give it a good clean out, blow done the jet holes etc etc. don't have a service kit so will have to go with a good clean out and check over. One thing I did notice when it was running a couple of days ago was there was no movement on the secondary venturi doors when I gave it some extra throttle. The mechanism is all working correctly on the bench, the primary circular doors on the bottom open ok and the secondary doors open ok when the tang comes around and hits on the mechanism when giving it more throttle, but as I recall the venturi doors did not open or even move, I know this is for when giving more throttle but I'm not sure what operated these doors, is it vacuum ? I have found a great tech sheet online which shows the correct path and fitting for all of the vacuum lines so I can test all of them and make sure they are on the correct ports etc. As for when the problem occurred, we bought her last October and drove her back some 300 miles , she had a little cut out just after leaving the guys house when going to get fuel, she did it a couple of times , just stalled out at the red light but started straight back up with no problems. we stayed overnight and then drove back the next day taking our time and she drove back at a steady 60 MPH without any problems. We took her out twice over the next 3 - 4 weeks and a couple of times she did cut out and one time took a little bit of starting again, with a little bit of misfiring and struggle . On the way home that day I had to keep knocking her into neutral when in traffic because she was stumbling. Other than that she drove home ok. She had been sitting over winter due to my ill health at the time so didn't get used apart from starting her up now and again. When I took her for her first run to get the MOT on her (government test) she started lovely, ran well til we got to the test station about 20 mins drive, she then just kept cutting out as soon as the test guy put her into drive. He eventually cancelled the test and we tried to drive home, she felt like she was running on only half the cylinders sometimes and would not go into drive at all without stalling out.She struggled to start at all for a while, misfiring running on only a couple of cylinders and one time giving off a huge backfire through the exhaust This lasted for quite a while until I took off the cover and tried to see what it could be. I cleaned up the distributor cap points and the electronic pick up points etc, the coil seemed to be very hot, more than usual, so cooled it down a little, she then started up after a couple of attempts and drove all the way home again without any fuss until we reached our house and she cut out again, started up straight away and she has been on the drive ever since. What I did with cleanng contacts etc could have been pure coincidence as we had been stopped for a good 30 mins and she could have cooled down enough on her own. I know it is really difficult to try and diagnose without seeing the engine and problems in the flesh so to speak but you are the only person on the net I have come across who has such in depth knowledge of this carb and its workings I thought it way have been something you had come across before. I don't have that box on the air cleaner you mentioned, just a straight forward air cleaner with attachment for a large breather hose and a small hose which goes to some screw in unit on the manifold which is plugged blank on one side and has a heavy metal pipe with a union going off to the front somewhere, and a heavy breather heading back along the top of the transmission tunnel to where I'm not sure yet. The vacuum choke pull off is working ok and the choke comes all the way off with the plates standing straight up in the air. The elctrics system is the electronic pointless distributor with the reluctor and pick up plate, with vacuum advance. I have replaced the coil with the correct unit and also the ballast resistor. I will change out all the HT leads too but I'm pretty sure although as I say inexperienced with this carb set up, that it is fuel starvation or vacuum problems, I am going to go get some vacuum hose today to change out any that's looks busted or cracked, having said that, they all still look very flexible and soft and not looking too worse for wear from heat damage etc. I think that's all the extra info you needed at present but if theres any more needed I will be only too happy to pester you and twist your brain with my problems lol , all joking aside your help is really appreciated from so far away from the man who I will come to name the Thermo Quad Specialist, many thanks Rocky, Colin
Bulldogcol Greetings Bulldogcol....Thanks, for providing, the much needed Information, that, will really help me, try to figure out, Your Engine's, tendency, to Stall at Idle Speed, when You put the Transmission in Gear/Drive......................First, I gotta Warn You, about "Re-Assembling" Your Thermoquad Carburetor, and, "Not Using New Gaskets", and the Other Parts, that are in a/the, Thermoquad Carb Rebuild Kit...............................There is a good and strong Possibility, that, by "Re-Assembling" Your Thermoquad Carb, "Using, the Old, Dried-Up, and, Already Squished, "Gaskets"...that, an "Air Vacuum Leak, and/or, a Fuel Passage Leak"...could materialize, which, could result in, an even "Bigger Back-Fire", due to, More Air, and Less Fuel, Making its way, into Your Engine, via Your Engine's Intake Manifold...!!!..................................The Accelerator "Pump's Plunger/Piston", is very Important, so Your Engine "Does Not Fall on its Face", and Hesitate, while doing just about any "Acceleration", more-so, from a standing start.............................The Needles and Seats (2 sets for a Thermoquad), are Needed, so, Your Thermoquad, Does Not "Start Flooding", and/or, causing Too Rich of an Air/Fuel Ratio/Mixture for Your Engine, at any given time.............................If Your Thermoquad, has those 2 "Nitrophyl" (looks like black plastic) "Floats", (inside it), and, if they start "Acting like a Sponge"...then, an "Overly Rich Air/Fuel Ratio/Mixture, it will be...!!!.................................If You want to do it right, and to have the best chance, at not creating any Un-Needed Headaches, by trying to save a few "Pounds" (Your Currency?), or Dollars, for that matter, then, as I see it, You'll be wasting Your time, and, more then likely, creating, even more, Engine Running Problems, that You have now...Yikes...!!!...lol..............................Here's what I would do, if I was the Proud Owner, of Your Motor-home......................................Purchase a "Rebuild Kit", for the Exact...9275-S...( I hope I got it right?) Thermoquad Carburetor...along with.."2 New Floats"...a "New Choke Pull-Off"...and that, quite Thick..."Gasket"...that goes Between, the Bottom of the Thermoquad carb, and the Intake Manifold (always remember, that, "New Gaskets"..."Prevent"...both..."Vacuum/Air Leaks"...as well as...Carburetor, Joint related..."Fuel Passage Leaks"...!!!)..................................I would do a..."Complete Ignition System"..."Tune-Up"...which Includes New Spark Plugs...and the Electrodes "Set", at the "Specified" spark plug..."Gap"..................................If the Distributor Cap & the Rotor, looked questionable, to me at all, then..."New Ones", it will be..................................If the Spark Plug "Leads/Wires', were old, or had lots of Miles/Kilometers on "Them", they would get "Replaced with a New, Correct Set"........................Once, all of the Ignition System Parts and Pieces, were replaced, as need be, then, I would "Check the Ignition"..."Timing"...and Adjust if Needed, to the "Correct...Setting/Specifications".......... Now then, about, how You were sayin', that, Your "Ignition Coil", was..."Too Hot"...while in Operation..................................I'm thinkin'...that, Your Ignition Coil is Mounted Horizontally, and, I actually had an Ignition Coil, start to "Leak Oil", as I found out, when I removed the High Tension Lead (looks, just like a short, spark plug wire), from the Ignition Coil's, Center, High Voltage, "Tower", and, I'm thinkin', if Too Much Oil Leaks out, that, as I see, just might result in, an Oil Filled Ignition Coil, possibly, starting to "Over-Heat"...maybe....................................Make Sure, that, Your..."Ignition Coil"...and, the..."Ballast Resistor" (2 or 4 Terminals?...and looks, kinda like, whitish colored Porcelain)..."ARE"...the "Exact"..."Specified Ones"...having the "Correct Part Numbers" on "Them", for Your..."Exact"..."Engine & Vehicle"...or, some Problems, may be the result..................................Your Engine "Stalling", at Idle Speed, while placing the Transmission, in Gear/Drive, could be...one or both...Ignition System"...related...and/or...."Fuel System"...related...as I see it, and also, from, all of the previous experience, that I've had the pleasure to entertain...head scratch...and, try to figure out, and, in the end, I Won, and, had great running engines, as a result of, what I had to do, to...make "it" happen...!!!...lol..........................If Your Ignition System, and, Fuel System, that includes Your Thermoquad, are Functioning, at a "Good Enough Level", then, all it might take, to keep Your Engine from Stalling, or almost Stalling, when You put it in Gear, might just be a matter of Adjusting the "Curb Idle Speed Screw or Solenoid", to Increase the Idle Speed, up to the "Specified Idle Speed", for Your "Exact, Engine/Vehicle Combination"...and/or...maybe the Thermoquad's "Idle Mixture Screws"..."Set To"...the..."Factory Specified Settings"...in order to produce, a..."Smooth Enough Idle"...and not Waste Gasoline, by being Set..."Too Rich"...at the very same time...hopefully...............................If You plan on making any Adjustments to Your Thermoquad carburetor, I find, that, by making any "Idle Speed"...or..."Idle Mixture"...Settings/Adjustments...while having the Engine Running, is to, have, for..."Safety's Sake"...the Automatic Transmission's, Gear Selector, Placed in..."PARK"...on Level Ground, and some Wheel Chalks/Tire Stoppers, so the vehicle..."Does Not Take off"...and cause any Serious Problems...!!!...................................Also, Make Sure, that, there is "Plenty of Fresh Air and Ventilation", when-ever the Engine is Running, as..."Exhaust Gas is DEADLY"...!!!.................................................................................When it comes to having, a Well & Properly Running Engine, both Performance-wise, as well as Economy-wise, it will usually require, that, a considerable amount of Money be Spent, for the much needed Parts & Pieces, that the Engine, and, any related parts, that "Make it Go"...or...Spare the Money...and Buy...Lots of Headache Pills...cuz...You'll probably..."Need-Em"...when You Engine, Finally...Quits Runnin'...in, the..."Middle of No-Where"...Yikes...!!!...lol................................Well, there You have it, for now that is, and....................Till next time.............Be Safe, take care, and have a good one.
RockysRoadshow Thank you once again Rocky, I shall take your advice and order a rebuild kit for my model carb, I found a company who had my listing in stock in the states $45.00. I shall also order a new contact pick up assembly for the distributor plus a new cap and a set of HT leads inc coil lead. Hopefully at some stage the fault will be cured by changing out everything. I shall keep you advised of the updates and hopefully once day soon will be able to say to you, yes she is fixed and on the road again running superb. In the meantime I will get on with it and be back to pester you if any more advice is needed,Cheers
Rocky,
Great videos, thanks much - you really know your stuff and I like that!
4 comments: 1) Do you have a vid on how to tune the accelerator pump, I dont seem to see that one, 2) my mixture screws are now 4 turns out and definitely better than 3 turns, is that OK? and 3) my idle does waver a bit and wonder if you can guess why that is, and 4) how the heck where and how - do I put a air cleaner mounting stud to keep the air cleaner from flopping all over the place! thnx, John
...when you tap the gas pedal, the fast idle screw drops to the second step of the fast idle cam, thus, lowering the RPMs (Revolutions Per Minute) of your engine, when its running....Now for "Hot" Engine Starting = Hold gas pedal about 1/4 to 1/2 way down as you engage the starter (all cars are a bit different from one another, just apply the amount that give the best result), as soon as engine starts, release the gas pedal, so the engine will idle on its own....(con't)...
Could you help me. our thermo quad caught fire in our rv i got rebuild kit but before and after cleaning I realized the valves don’t open? I tried Ed 40 and nothing
Greetings...Linda Burkett.........Thanks for watching.........Better late, than never, I guess (me, that is).........You have probably got it fixed by now, but, I'll still put in my 2-cents worth, never-the-less..........Carb fire...got really hot...bottom and top are made out of aluminum, which melts (and warps), at a lower temperature than steel or iron........Might be, that the throttle shaft/s seized, where it goes through/into, the TQ's throttle body (base plate), or maybe, the linkages got all distorted or whatever perhaps.........If you care to, you can let me know, what the conclusion was, to your mishap, and what the cure, ended up being, thanks.....and.....till next time......Be Safe, take care, and have a good one.
Hi Rocky. Following up from my previous problems. it turned out to be the electronic contact unit in the distributor that was causing my hot die out problems. Anyhoo your help on the thermo quad was superb and I now have a rebuild kit as you suggested, I was having a problem on our last run out with massive fuel consumption and after watching your videos again a couple of days ago I have figured out a major problem is the secondary air doors are not open, I have ordered a new choke pull off which hopefully I will get in the next week or so from the states. I need to ask one question though if I may, how do you set up the fast idle correctly, my choke wasn't coming off fully which would contribute to the fuel consumption along with the none opening air doors, I want to rebuild the carb and also set it up spot on so to maximise fuel consumption because she is using so much it is actually limiting our use of our RV because we cannot afford her getting just ten mpg, I'm sure a rebuild and full set up with the secondary doors opening will almost double our gas mileage. I have watched and read a couple of blogs where people talk about the "special" noise from the carb when the secondary air doors are drawing in, I haven't heard this noise yet but look forward to it. Could you point me in the direction of your video that deals with the setting up of the choke fast idle please or is it a simple question of making sure it goes onto the bottom step when the choke is fully off. Thanks again Rocky and hope you're ok ovet there in Canada ☺
+Colin Gowland Greetings Colin Gowland....Good to hear, that You found out, what the problem was, with Your Distributor..................If...???... it is the Reluctor (has those teeth on it, that spins with Your distributor's shaft), and is very Close to, that Magnetic Pick-up Unit, I hope that, You "Set that (air) Gap", to "Specifications", with a "Brass or Non-Magnetic", type of Feeler Gauge", cuz, if that "Gap", is Too Big or Too Small, Your Engine, might not Work, as good as it should be, and maybe, might have some Ignition Miss-Firing, possibly.................................I hope that, if and when, You have, or, are going to, "Rebuild" Your Thermoquad, that You "DO", install, "2 Brand New Floats", Especially, if the ones, that, are/were, in there previously, are made of that "Nitrophyl" Material (looks, kinda like, black plastic)..............A while back, I had, one of those..."Nitrophyl Floats"...in a Thermoquad Carb..."Sinking"...as in Sunk, or partially Sunk, and, it kinda Acted, just like a Sponge does, as in, "it" Absorbed Gasoline, causing it to "Sink", and Didn't actuate the Needle, inside its Seat properly, which Allowed "Way Too Much Gasoline", into that particular "Float Bowl" (there are 2 of them), which causes, a "Way Too High, Wet Fuel level", and, the result was, "A Way Too Rich Air/Fuel Ratio"...for the Engine to Burn Properly, and, the Smell was Obnoxious, to say the least...!!!........................You can "Check", to see, some-what, for, proper Operation, of the "Choke Plate", on Top of the Thermoquad, and "Fast Idle Screw" (that be, the Big Heavy Screw, that makes contact, with those Steps, on the fast idle Lever/cam), and the Linkage, that actuates them, by doing the following.....................With Your Engine "Cold and Not Running", Remove the Air Cleaner Housing's "Lid" just simply, pull down, easy now, on that "BIG Fast Idle Screw", and when it hits Bottom, make sure, that the Small "Tip", of that BIG Fast Idle Screw, is in that "Notch", at the Bottom, of all of those "Steps, on the Fast Idle Lever/Cam", and "Wiggles Freely", up and down, just a small amount, without making any Contact/Interference, with that very same, Fast Idle Lever/Cam, and, make sure, that, the "Choke Plate", is Fully "Vertical", while You are holding, that BIG Fast Idle Screw Down, at the same time..............................Sometimes, the Choke, and/or Linkage, gets Sticky or Stuck, so, make sure, that, it's all "Wiggly and Free" from hangin' up...............................Well, when that Secondary "Air Door", Opens Up, as far as it's able to", and You are able to hear, that, very impressive "Growl", that's not Fuel Economy, that You'll be hearin', it'll be the "Mad Rush of Gasoline"...(and the Air, required, to go with it, in the order of, an Air/Fuel Ratio/Mixture, of approx. 12.5 to 1, as opposed to just cruzin' along, be-in, at the 14.7 to 1 Air/Fuel Ratio/Mixture, there-abouts)...............Also, if the Factory/Stock, Sheet Metal, Air Filter..."Housing", is installed on the Engine, it will usually "Muffle" that "Growl-ee Sound", that Ur dyin' to hear, by quite a bit, as in, a reduction of Decibel/Loudness, as opposed to, the much Louder Growl-ee Sound, that Others will be Hearin', while having, something like, a rather Open/Un-Obstucted/Un-Restricted, Air Filter Unit, on Their..."I Wanna Hear it Roar, and I Wanna Hear it Roar Now"...Thermoquad equipped Engine!!!...lol...............................................The "Instructions" (sheet/s of paper), that are usually included, in the Rebuild Kit, should give You, a pretty good Understanding, of what needs to be done, as it applies, to the Rebuilding, and Setting-up, of Your Thermoquad Carb...........You have to..."Make Sure"...that You..."Follow the Sequence"...as in the..."Order of Setting-up the Linkages and Adjustments"...on Your Thermoquad Carb, according to, the (usually), Numbered Pictures, and what You Read in Print, on the Rebuild Kit's, "Instruction Sheet/s", that, as I've found, that will Show You..."How to Do It Correctly"...or, just like tryin' to Assemble "IKEA Furniture", and not doing it right, You'll probably, have to go back, and "Read the Instructions anyways"...!!!...lol...Not to worry though, it's usually a Guy Thing, where we usually..."Read the Instructions"..."LAST"...!!!...lol.................So, to Avoid..."Going on a Wild Goose Chase"...do Yourself a favor, and really study those "Instructions, that come with, the Rebuild Kit"...!!!................................Also, the "More %-age/Per cent-age", or Amount of "Ethanol/Alcohol" (if any, that is?), that is in the Gasoline "Blend", that You put in Ur Gas Tank, will usually, cause, the Non-Feed back, type of Thermoquad Carbs, to Supply the Engine, with a "Leaner Air/Fuel Ratio/Mixture, as compared to that good ole Gasoline, that Never had any Ethanol/Alcohol in it, and, if Ur Engine, starts to "Lean Surge" on Ya, while just Cruzin' along at City Speed, that Ethanol/Alcohol, might just be the Culprit, that's causin' it, perhaps.................Remember Now........Install..."2 New Floats" (if, there were those Nitrophyl/black plastic ones, in there previously).........and a New "Choke Pull-Off"...cuz, sometimes They Stick, or get too Slow, or, maybe even have an unwanted Air Leak, in its Diaphragm, perhaps..............................Sorry, but I don't have any actual Thermoquad Carb, "Adjustments/Set Up" Videos, at the moment....................I hope that, Your Fuel Pump, "Is Not" putting out, too Much Fuel "Pressure", cuz, the Floats, will not have enough Force, to apply to the Needles, to Stop, any Fuel Pressure, that's Above, oh, about 7 PSI/Pounds per Square Inch, or, put it this way, Fuel Pressure, Over 10 PSI, is, Way Too Much, just sayin' now..............................To have the best chance, at having Your Thermoquad, "Run/Perform, and with good Fuel Economy" as well, it's almost a no-brainer, well, for me that is, to have, all of those, very old/high mileage "Thermoquad Parts"..."Replaced with New Parts"...and also, be..."Set-up/Adjusted Properly"...as well, cuz, from my past experience, there's No Other Way...!!!...lol...................Let me know, when You get to the point, of actually "Rebuilding Your Thermoquad Carb", or, it'll probably, just end up, be-in, another one, of those..."Wild Goose Chases"...!!!...(and yes, I know all about..."Them"...!!!...lol).......................Well, things, here in Canada, are Eh-Oh-Kay...Thanks, and, I hope, all is Well, with You, and Yours as well............and.........till next time...............Be Safe, take care, and have a good one.
@WindowsIP Might not be the Carburetor? To me it sounds more like a Vacuum Leak. Check vacuum hoses and what they connect to for Vacuum leaks. Intake Manifold Gaskets, and nuts/bolts tight? There are so many things that can cause your fluctuating idle. If it is Computer controlled, check for trouble codes. Check EGR Valve and connections. If Carburetor has lots of miles/kilometers on it, a carburetor rebuild may be what is needed. Try to get a good Book on your Carburetor, it should help.
What would you do different in lean burn?
Greetings...belloa3026......Thanks for watching......You asked, what would I do different, when it comes to lean burn........Well, it all depends upon, what you want it to end up as, as in, almost stock/factory, so it will have all of its factory parts and pieces, so it will pass a visual test at the smog testing station? (maybe)..........If the vehicle does not have to go through the smog test, and the area where you live, doesn't care how the vehicle is modified, then, there are, quite a few things that I would change alright.........I would get rid of the lean burn system altogether..........A different distributor, that has advance weights and springs, and a vacuum advance unit mounted onto it, so it will work, shall we say, the old school way........I would also get a basic looking thermoquad carburetor, much like the thermoquad, that you see in my youtube videos, that does not have all of those extra parts and gadgets, showing on the outside of the thermoquad carburetor, that way, it will be much easier to work on, and tune as well........I've never had, or worked on a lean burn system at all...........Do a search on youtube, for people that have done, the elimination of the lean burn system, in order to see, all of the work that needs to be done, if that's what you're really after, in the long run........You can still, just rebuild your lean burn thermoquad, by getting a rebuild kit for it, if you want to........If you do, then, buy 2 new "Brass" floats, as those black/nitrophyl floats, can at times, absorb gasoline, and start to sink, which will cause a rich (air/fuel ratio), running thermoquad.........Good luck with, what choice, you might make, and.....be safe, take care, and have a good one.
Now, about a leaking Thermoquad....If you notice lots of fumes coming from your exhaust systems tail-pipe (make sure you Never run an engine with the Garage Door CLOSED!!!), that could be one or both Seals inside your Thermoquad drying out and shrinking causing a leak...could also be one, or both Floats starting to Sink! (if they are the Plastic ones)...also if you notice any gasoline like smell on your Oil Dipstick when you check your oil level...Those are some possible "Tell-Tales!"...(con't)
Now, on to the Stud!...lol........It looks like my "Display" Thermoquad doesn't have an Air Cleaner Mounting Stud at all !!!........Oh my goodness !!!......Ok, here's the lowdown on the subject........Have a look at the secondary air door nearest the center of the carb (on top) and you will notice a square cut-out there........Down under is a Threaded hole that has a 1/4" - 20 T.P.I. or (One-Quarter Inch Diameter times 20 Threads per Inch tapped hole, I think...) Insert correct stud length!
Hey Rocky. I was wonder if you could help me with something. I have the 800 CFM thermoquad off of a 77' Chrysler Cordoba that I still own. I'm having a problem with gas evaporating out of the float bowls, which makes it hard to start. I'm not if there is a leak, or if it evaporates quick naturally. It only does it if you leave it sitting for more than four days or so. It always starts, but its a major inconvenience. Is there any way to test for a leak?
...Cold Engine Starting = Push on gas pedal and release...start car...when engine starts, it should be running at high RPM's...tap gas pedal, that should lower RPM's a bit so the engine doesn't star screaming at you!...lol...What that does is set your Choke valve (plate), and sets the fast idle screw on the highest step of the fast idle cam before you start cranking the engine... when engine starts, RPM's are a bit too fast...then...(con't)...
What if it only idles up turning counter clockwise. Righty idles mine down. It's a 1978 Dodge W100 360 4 bl thermoquad
Bernardo Rangel Greetings Bernardo "Cricket" Rangel....Thanks for watching, and for Your comment (question) as well.................................It appears, to me, that, Your "Idle Mixture Screws" (those be, the 2 Idle Mixture Screws, found, in/on, the Lowest part, and, at the Front of Your Thermoquad Carburetor) are Working, just as "They" should be Working, in that, You are Hearing, Your 360 Engine's "RPM's (Revolutions Per Minute), going, both, "Higher", and "Lower", when-ever You happen to "Turn", one or both, "Idle Mixture Screws"..."In or Out" (In = Clockwise rotation...and...Out = Counter-Clockwise rotation), while the Engine is just at "Idle Speed"....................For the most part, as it pertains, to a Thermoquad Carburetor, while having the Engine, up to Operating Temperature, and at..."Idle Speed"...then, Turning, one or both..."Idle Mixture Screws"..."In/Clockwise"...will usually..."Lean-out", the "Idle Mixture" (or, Air/Fuel Ratio)..................................When Turning, one or both..."Idle Mixture Screws"..."Out/Counter-Clockwise"...then, the..."Idle Mixture" (and again, I say...or, Air/Fuel ratio...lol), will usually..."Richen" (as in, Make Richer), the..."Idle Mixture" (or, Air/Fuel Ratio)..................................How, a Thermoquad's..."Idle Mixture Screws", actually "Get Set", as in, Full and Partial Turns, "Out", from, just being "Lightly Seated" (aka, Fully Turned...In/Clockwise...until they Stop), depends on, wether or not, the Vehicle in question, has to be..."Emissions Tested"...???................................I've used, what is called, the.."Lean Drop Method" as it pertains to, how I Adjusted both "Idle Mixture Screws", as well as the "Idle Speed Screw", to arrive at, an "Air/Fuel Ratio" (Mixture), that would, shall we say..."Lower/Reduce, the Emissions/Pollutants"...that were Exiting my Tail-Pipe, or, Tail-Pipes, as the case may be, and, be, Under the Maximum Allowable Emission Limits, as set forth, by, that, rather "Sensitive"..."Poice-Tracking-Dog-like"..."Computerized"..."Tail-Pipe-Sniffin'-Equipment"...at the..."Vehicle Emissions Testing Establishment"...that..."Just Can't be Fooled"...or, can "It"...???...lol...........................If, the Vehicle in question "Does Not" have to be "Emission Tested", then, it's, that much easier, to set-up, the "Idle Mixture Screws", and, the, "Idle Speed Screw" as well..............................Here's the Deal....................We Don't want those "Idle Mixture Screws"..."Set Too Rich" (as in, Out/Counter-Clockwise, from being Lightly Seated), as, by doing so, Gasoline gets Wasted, that the Engine, really Doesn't need, while just sitting there, Idling away.................................Also, we Don't want those "Idle Mixture Screws..."Set Too Lean" (as in, Turned In too much), or, that in itself, can at times, cause, what is known, as a "Lean Miss-Fire", where-by, the "Idle Mixture" (Air/Fuel Ratio), while, being "Set Too Lean", will at times, make for, an "Idle, Air/Fuel Mixture", that "Won't Burn Properly", and, cause the Engine to "Miss-Fire", and, all of that Gasoline, that Doesn't Burn, some-what, Completely, gets sent, out of the Engine's Exhaust Valve, and through the exhaust system it goes.......................................If the Vehicle "Does Not", have to be Emissions tested, then, here's a rather simple, and Basic way/method, that, I, in the past, use to do/perform, on an Engine, that had a Carburetor, that Did-Not, have any Smog-Gadgets, mounted on it...............................Before "Starting the Engine", Make Sure, that, there is Plenty of "Fresh Air and Ventilation", as "Engine Exhaust Fumes are Deadly"...!!!........................Get the Engine, Fully Warmed Up, and make sure, that, the Choke is Fully Off as well................................Shut the Engine Off, then Hook-up a Tach (aka, Tachometer), then, Lightly Seat, the Idle Mixture Screw/s, and Place a "Chalk-Mark", on "Them", closest to the Sky (12-Oh-Clock position)...then turn them Out, oh, about 4 Turns, then, Start the Engine.....................................Lettuce say, for Example (Only!), that this Hypothetical/Vehicle had an Automatic Transmission, and, that, the predetermined/hypothetical..."Final"...."Idle Speed", was "600 RPM", with the Automatic Transmission In Gear, and my Foot is on the Brake! (as in, when I'm all Finished, said, and done)................................I would make my Adjustments, while the Automatic Transmission was in "PARK", for Safety Reasons, and, have the Vehicle on Level Ground, with the Parking/Emergency Brake On, and also, while having some Bricks or Lumber, to Block the Tires, so the Vehicle...Doesn't go, on a "Trip" of its Own...!!!..................................I do my Hypothetical, "Idle Mixture" Settings, while the Automatic Transmission, is in "PARK", at "700 RPM's", because, when I'm Finished, all said, and done, and, when I finally get around to Placing the Automatic Transmission in "GEAR", the "Idle SPEED", will usually, "Drop Down/Reduce", about "100 RPM's", give or take a bit, depending on the Engine be-in worked on ,............................Then, I would keep a close watch, on the Tach/Tachometer, when the Engine was running, and, any time, that I was Adjusting, the "Idle Mixture Screw/s", I would Make Sure, that, if and when-ever, the Engine "RPM's"...Went-Over, that..."700 RPM's"...I would "Re-Adjust", the..."Idle SPEED" Screw, back to that "700 RPM's", with the..."Idle SPEED Screw Only"...!!!................................You see my Friend, and, as You have probably already noticed, is that, when-ever Turning the "Idle Mixture Screws", with the Engine Running, the Engine's "RPM's", will usually Change, with at least One Exception, and that Exception is...........................When an Idle Mixture Screw, reaches "its", shall we say "Rich Limit", kinda like, when "Turning Out" (One Only), "Idle Mixture Screw", there is usually, a point/setting, where-by..."Richening/Turning-Out"...the..."Idle Mixture Screw"...Any..."Richer/Out"..."Does Not", seem to Change the Engine RPM's much, or, not all all, and, that to me, is, probably, just, like I was sayin' earlier..."Just a Waste of Gasoline"...!!!...lol...but, then again, that "Rich Limit", well, once You hit it, that is, is "Still a bit on the Rich Side", and, is still, for the most part...."Wasting"...that..."Liquid Gold"...!!! (aka, Gasoline)..................................What I'm really after here, is, tying to get, the Idle Mixture Screws, "Set", about the "Same Amount", of, "Turns and Partial Turns" out, from being Lightly Seated, in order to, shall we say, have them both "Set", so that they are some-what "Balanced", to, One-Another...rather then having, One Set, Out Too Far, and the Other One, In Too Far (as an example).............................I Adjust the "Idle Mixture Screws", so, the Engine, "Idles Fastest", while keeping the Engine RPM's at that, in this case...700 RPM's", with the "Idle SPEED Screw", cuz,, if I Don't, the Idle Mixture, is probably, gonna be "All Messed Up"..................................You can use a Tachometer, or, a Vacuum Gauge (to get Highest Vacuum reading), and, I've even got pretty good results, just Use-in my Ears/Hearing, while Setting, both, Idle Mixture Screws, as well as, the Idle Speed/Screw.................................Just make sure, when, all's said and done, is to..."Not have the Engine's "Idle Speed Too Fast, in Park, or In Gear"...!!!...as, if the Idle Speed is..."Too Fast"...and, You go from "Park, to In-Gear"...then it usually goes "KLUNK", Big Time, when You do so...!!!...and...once, In-Gear, the Vehicle, will usually..."CREEP"...as in..."Move on its very Own, and probably, Too Fast as well"...and..."Your Foot Was Not On the Gas Pedal"...at all...!!! (to lol, or, not to lol, that is the question)...................................Yeah, I know, that, it may seem to be a bit Tricky at first, but, with a bit more time spent, just as I have, You'll know what to expect, some-what, as to, what's go-in on, when making some Adjustments, from time to time.............................Just, keep in mind, that, "Gasoline, Internal Combustion Engines"...tend, to Get..."Zero"...Miles per Gallon...when...the..."Engine is Running"...and...the..."Vehicle"..."IS NOT MOVING"...!!!...lol................................So, that's about it for now, and...................Till next time.................Be Safe, take care, and have a good one.
left is richer, right is leaner. Most all ThermoQuad have a high and curb idle speed screw. Fast idle is the long screw on top, curb idle on bottom. the fast idle cam often wears out. if it works, set fast idle at 1200. curb idle should barely touch the throttle plate link. if the motor won't run unless curb idle screw is in, advance the timing and/or adjust mixture so it will idle with little or no added idle air.
+Pete Kranz ....Greetings Pete Kranz....Thanks for watching.................There are a number of things to consider, and to be aware of, when it comes to a Thermoquad Carb equipped, factory/stock, engine and vehicle, and it gets kinda Fussy, when that Thermoquad Carb, has to make it though, Smog/Emissions Testing (just ask me, cuz, the adjustments/setting-up, that I did in the past, worked really good, and I got some pretty impressive smog reports to prove it...lol)....................There are different Specifications, for different engine/vehicle combinations, for a Thermoquad's Fast Idle Speed Setting, such as, which Step, on the Fast Idle Cam/Stepped Lever, that the Fast Idle Screw should be on, as well as, whether the setting, is to be done, on a cold (bench setting?), or, hot engine as well........................As for the Factory's way of doing things, when dealing with a Stock/un-modified Engine, and having the Engine warmed up to Operating Temperature, the Primary Throttle Plates/Butterflies, at warmed-up, curb Idle Speed, should be Opened-up, just enough, to expose, the Transfer Slots, so there's, what appears to be, a Square Shaped Opening there-abouts, of the Transfer Slots showing, as viewed from the Bottom of the Thermoquad, in order to have the Thermoquad, Transition smoothly, and properly, from curb idle speed (idle circuit), up to where, the Primary Main Circuit (primary main fuel jets and metering rods) take over, and yes, with a little help from the accelerator pump as well...lol..............I went, and got hold of, my good ole Thermoquad, that You see in all of these videos, and I closed the primary throttle plates/butterflies 100%, and, there was..."No Transfer Slots Showing At All"...!!!...Yikes...!!!...lol........................Some Carburetors, do have a separate, and adjustable Idle Air Bypass Circuit or what-ever in them, and, even so, I would have a very close look at that Carb Manufacturer's Instructions/Specifications, to make sure that, the Primary, and/or Secondary Throttle Plates/Butterflies were in the "Correct Position" in relation to the Transfer Slots.............Oh, and, the Big Heavy, Fast Idle Screw, is on the Bottom, "Under" the Curb Idle Screw (I had to look, to make sure...lol)...................Then, if the Thermoquad has a Curb Idle speed "Solenoid" on it, mounted on the opposite side, in relation to where the Big Fast Idle screw, and that, so called curb idle screw is located, well, that "Solenoid", is for Setting the Warm Engine, Curb Idle Speed, and that Screw, that we were just calling, the Curb Idle speed Screw, that's just Above, that Big Heavy fast idle screw, would usually be set, oh, about 100 RPM's (that be-in a Specification, that I might recall), Lower than, the Curb Idle speed "Solenoid" was set at, when at, the proper, warm engine, curb idle speed, in order to Prevent the Engine from Dieseling/Running-On, when the Engine was shut off, how about that...lol......................Now then, let's talk, a little, about Ignition Timing, as it applies to, a Distributor, that has centrifugal advance weights & springs, along with a Vacuum Advance Canister/unit on it as well, shall we.......You were saying, to Advance the Distributor's Initial (base) Ignition Timing, from, where it was already set at......................Well, there's a lot more to Ignition Timing, than You might think.................Sure, by Advancing the Distributor's Initial (base) Ignition Timing, at Idle Speed, it's pretty much a given, that, the Engine RPM's will Increase, to a point, alright...But...be Aware, by doing so, that, every other part of the Ignition Timing Curve, will Advance also, why is that Important You ask...???...well, let's say for example, that the Distributor's Initial (base) Ignition Timing has a Specification of 5...Degrees BTDC/Before Top Dead Center (crankshaft degrees), and that's a typical Smog Setting, oh, and, the Advance Canister/unit, is hooked up to a Ported Vacuum source, just so You know (cuz, it needs to be, for smog testing, in this example), and let's say, You went ahead, and Added another 10 (crankshaft) Degrees to it, to get that really nice Idle, now we're at 15 (crankshaft) Degrees BTDC....................Now then, the Total (that's the Initial/base degrees, added to the centrifugal/weights degree amount) Ignition Advance (please note, that Total, "does not" include the vacuum advance, and it was probably the racing crowd, that never used vacuum advance, that used that Total, description word, as my best guess), was already at the "Maximum" Total Ignition Advance, of, oh, let's say it's 35 (crankshaft) Degrees BTDC, shall we..................So, now, we just Added, that very same, Extra, 10 (crankshaft) Degrees BTDC, to that already Maximum Total of 35 (crankshaft) Degrees BTDC, and now we have a Total of 45 (crankshaft) Degrees BTDC, and the Gas Pedal gets Stomped-On, and, is now at WOT/Wide Open Throttle...then, all of a sudden, the Engine goes...knock...Knock...KNOCK...BANG...BOOM...!!!...then silence, as the car, starts to lose speed, and onto the side of the road...it gets parked.......................The Most Important and Critical Ignition Timing Advance (crankshaft) Degrees BTDC Amount, as I see it, is when the Engine is going WOT/Wide Open Throttle, and also, when there is, a High Engine Load involved as well, cuz, that's usually where the Most Engine Damage will occur, and in a very short time-frame as well.........................So, it's kinda like that good ole sayin', and that sayin' is..."Look Before You Leap"...and in this case, I'm referring to, having a Plan First, and make sure that, the Ignition Timing Advance Curve, is "Safe" for the Engine, under All Operating Conditions, or a Person, might have Expensive Engine Damage, by not doing Their Homework First...........It's pretty much, a Whole New Ball-Game, when-ever an Engine gets Modified, and much more so, when that Engine's, New, Go-Fast Parts, start to fall in the category of..."Extreme"...!!!...Yikes...!!!...lol.........So, to play it Safe, go easy on the Ignition Timing Curve, especially on the Total (crankshaft) Degrees BTDC at WOT/Wide Open Throttle, or, maybe, bye Bye Engine, and, I sure hope not, and........till next time......Be (Ignition Timing) Safe, take care, and have a good one.
You add crank timing to base timing to get total timing, and most LA blocks ran best around 33 - 35° all in. Adding vacuum to that, and you should be 48 -58° total mechanical and vacuum all in (depends on distributor or ESC computer).
The problem with tuning a TQ is whether or not you have the right jets and rods for your carb and application. I've had a few where the rods didn't match, or it was a "360" carb with 318 rods and jets. Then the floats leak, the bowls leak, transfer tubes leak, accelerator pump cup leaks, or I've even found the check ball missing.
+Pete Kranz ....Greetings Pete Kranz....I hear Ya, when it comes to, what seems like, a Lot of Ignition Timing Advance, when the Vacuum Advance, from the Vacuum Advance Canister/Unit (in crankshaft) Degrees BTDC, is Added to, the Total (Initial plus Centrifugal/Weights & Springs)...and...(in this Example, Total = 35 (crankshaft) Degrees BTDC ,for a Factory Stock, Low Compression, V-8 Engine, so, we would almost be guaranteed, a nice Strong amount of Manifold Vacuum)...........................A Factory installed, Vacuum Canister/Unit, for this particular Distributor, would usually have, a Pre-Set, Amount of Vacuum Advance built into it, so, when it was Maxed-Out, and Added to the Total (Initial and Centrifugal/Weights), then, we should arrive at that "Magic" Number, would we not...???.....................As You were saying, up to 58 Degrees, but, for me, that seems a bit on the high side, but, with a functioning EGR/Exhaust Gas Recirculation System, Diluting, an already Lean Air/Fuel Ratio/Mixture, it could be possible, due to a very Lean Air/Fuel Ratio/Mixture, needing, so much more Ignition Timing Advance, to arrive at, what the Engine needs, while under a Light Engine Load, to have the Peak Cylinder Pressure occur, at about 15 (crankshaft) Degrees "ATDC/After Top Dead Center", to get that, good ole, Good/high as possible Gas Mileage, which ultimately, reduces the Gasoline Bill...but only if, You or I, can keep the Go-Fast Pedal, Off of the Floor...!!!...lol.............Unleaded Gasoline, with about 10% Ethanol in its Blend, as I've experienced, with a Thermoquad Carb of mine, tends to Lean-Out the Air/Fuel Ratio quite a bit, and I had to Re-Jet (Enlarge), a TQ's Primary Fuel Jets, from Ninety-Five Thousandths of an Inch, all the way Up-To, One Hundred (and) Four Thousandths of an Inch, just to get rid of, that very annoying Lean-Surge (Car was Bucking back and forth), while just maintaining city speed, that I was havin' a few years ago.....................Gotta remember, that, this particular TQ was Calibrated on the good ole Gasoline of the early 1970's, that never did have any Ethanol/Alcohol in it what-so-ever.........................I actually have a UA-cam Video, on how I Enlarged those two TQ Primary (fuel Jets), along with a Tapered Gauge, that I made out of, a piece of coat hanger wire, and used a felt pen and a micrometer to measure the hole/orifice size of the Jet, that was showing up on the Gauge, of those two measured, Enlarged Primary Jets......................Also, in this very same TQ, I put some Truck Metering Rods in it, (2024's if I recall correctly), where-by, the Large Diameter was super close, the Taper was reasonably the same, but the Power Tip Diameter was Three Thousandths of an Inch Smaller than the Original ones, and, the result was Super, but one more thing to make it Super-Duper (lol), that I did, was, I made up a Custom, Choke Pull-Off linkage "Rod", that actuates the Choke "Only", and now, has nothing to do with Controlling the Secondary Air Door/Valve at all...................Only the Torsional Wind-Up Spring (was set at the Factory Specification, of, 1 and 1/4 Turns), Regulates the Opening of the Secondary Air Door, and Man, once the engine is at operating temperature, it Goes Like..."!#%&*%#!*#...and then some...!!!...and never hesitates, bogs, etc............This awesome Mod that I did, was on a TQ equipped, small block Dodge, 4 Speed "Standard" Transmission/with a Clutch, so, I can't say, whether or not, it would be as Awesome, or even work for that matter, if done to a TQ, that was on an Automatic Transmission Car...???.......................The only real problem I had with Nitrophyl (looks like black plastic) Floats, was when one of them, decided to become a Sponge, and absorbed Gasoline, and started to Sink, as, I found out, while having, what seemed to be, a Choke related Engine problem...............Yes-Sir-ee-Bob, when I looked down, into the TQ's, passenger side, primary throttle bore, while the warmed-up Engine, was running at idle speed, there it was, the Primary Nozzle, was goin'...Drip...Drip...Drip..........No More, I wanna Be a "Sponge", Nitrophyl Floats for this Kid...Only Brass Will Do from Now On...!!!...lol.......................Have You Seen that 4-Barrel Street Demon Carburetor, that came out, just a few Years ago...???............They sure have, what looks to be, lots of TQ Features on it/them alright..................Can even get one, with that good ole black/plastic lookin', center section on it, that, as they say, should keep the Gasoline, about 20 degrees Cooler, that an all metal carb.................I might just get me one, some day.......................Well, that's about all for now, and..........till next time..........Be Safe, take care, and have a good one.
Greetings Dutch....Try this first...Start your Cordoba "1" Day after it was running last....Your Cordoba should start much quicker, providing that your Starter and Battery are performing at their best....Listen to how fast the engine "Cranks" over, and count how many seconds the starter is operating before the engine is actually running on its own...and, are you using the "Correct" Procedure to start your Cordoba, as per your Car Owners Manual?....(con't)...
...Now, about Gasoline....Gasoline, as compared to the Gasoline of the 1970s is about 3% "Leaner" then it was back then...Just that alone can cause any Carburetor to run a bit on the Lean side (Air-Fuel Ratio), when considering that the Carburetors back then were "Calibrated" using the Good Old Stuff! (Gasoline), and yes, the longer you let your Cordoba's Engine sit, without running, the less fuel there will be in the float bowls, due to Evaporation (and maybe leaks too!)...Take care, my Friend