Greetings Bossman........Actually there are Two "O" Rings, and sometimes they get "Stuck" in the bottom of the Phenolic Resin Float Bowl.......Use a Flashlight...(make sure that there is Not any Gas or Gas Fumes in your Float Bowl).....and look carefully and see if they are Stuck at the bottom.....In the earlier ones, they used to have Leather or some kind of Gasket material that got really dried up, especially if the engine hasn't been running for a long time.....No "O" Rings = "BIG LEAK!"
Thank you for uploading your videos on the thermoquad, having an american car in the uk most people dont know what a 4 barrel is let alone one that is as …. special … as this one. Gave you a like and subscribed
Greetings...Chris Nichols...........You're welcome, and, thanks for watching, oh, and, thanks for the "like" too...........Lem-me-see-now...hmmm...an American car, on the U.K.'s motorways...??? (I think that's what they might be called?), as in, damn, the..."steering wheel"...is on the "wrong side" of the car...!!!...lol...........If a Thermoquad carburetor, is calibrated properly (jets & metering rods, etc.), and, is also set up correctly, then, it's usually known, that, it'll perform like a beast, well, at least, it usually does for me, on a good day that is............For starters, make sure, that, the two "floats", are in good shape, and are floating, in/on top of the gasoline, in the two float bowls "correctly", as in, sometimes, the nitrophyl, type of float material (looks, kinda like black plastic), can sometimes, over time (years usually), start to act like a "sponge", and start to absorb gasoline (petrol), and then, the "wet" fuel level, in the float bowl/s, will usually become too high, and then, a richer then wanted, air/fuel ratio will be the result (as in, maybe, carbon fouled spark plugs, as well as, poor fuel economy), oh, and, same result can happen, with (hollow) brass floats as well, when-ever a pinhole sized leak, in the brass, or, even in the solder, that secures, both halves, of the (hollow) brass float together, takes place...........If you haven't already done so, do an internet search for...Vaanths Thermoquad Guide...(I hope, that I got it right), and, hopefully, a few of the websites out there, will have a link to it, and, once there, there is lots, did I say Lots, of Thermoquad carburetor information, to be had, and then some............The gentleman that wrote it, did a fantastic job, to say the least...........Enjoy your American ride, in the U.K., even if, some folks, give you funny looks...lol...and........till next time.......Be Safe, take care (watch those "speeding tickets"...lol), and have a good one.
I watched all your videos. all are great and informative. One thing baffles me. I have a 1971 carb off my 1971 duster340. Air horn inside is nothing like what I am seeing here. Have rebuilt it several times in the last 50 years. Still can't find the o rings you talk about. Car runs good as it did in 1971.
Greetings...farmer7465...…….Thanks for the nice comment, and for, watching too...……The proper "rebuild kit", for your "exact" carburetor model number, will hopefully have, the "O" or "X" rings in it (the model number, is usually "stamped into", the lowest part of the Thermoquad carb, at one of the rear corners, and, is usually..."four numbers, followed by the letter "S")…("don't use", the numbers/letters, that are cast into the top of the carb...!!!)……….Those two "O" rings, might be stuck, at the bottom of, the (phenolic resin/black center section's) cavity/s, where the two, (top of the carburetor's), aluminum, fairly long, downwards/protruding parts, fit into (yes, they can get stuck, and be "hiding", so, shine a bright flashlight, down in there, in order to see, if they are in there, or not)………...Check out...Vaanths Thermoquad Guide...on the internet, who's "link", will hopefully, still be posted on some websites...……..The Thermoquad information is very good, and, the guy that wrote/compiled it, did a super job, to say the least...……..Those 340's, had a really good reputation, back in the day...…….The 360, was the engine that replaced it, but smog/emissions, lowered the compression ratio, along with, some of its power output too, but, in 1974, it still had, 245 Horsepower, and, 320 Foot Pounds of Torque (please note, that, in about 1972, they changed, the..."actual"...engine's Horsepower and Torque, to the "Net" system, which is much lower, than, the rating system, that, your 340 was probably rated with)……….."Net" horsepower and torque, as far as I recall, was, by having, most of the engine's, external components, hooked up and operating, and maybe, with some drivetrain losses, thrown in there as well, maybe...I'll have to look it up, sometime)………..Many moons ago, a Chrysler dealership, parts, counter guy, told me that, that, 245 "net" horsepower, would probably be, about 285 Horsepower, as I recall...…….Your 340, is definitely a "Keeper", so..."Keep it"...lol...…...Enjoy Ur ride, and......till next time......Be Safe, take care, and have a good one.
@@RockysRoadshow As I say, my 1971 4972s is nothing like the later thermoquads. The competition series and the 1971's are air metered. Many differences inside. The resin bowl is all together different. No o-Rings. I have not yet run across a video on this. If you can, get a hold of one of these carbs, and check the differences. I have pictures, but can't figure how to send them to you. I am old school, got left behind in the cyber circle.
Greetings...farmer7465...……..Now that you mention it, I do recall hearing about, the air-metered version of the Thermoquad, a long time ago...……..If you ever need any parts for it, then, E-Bay, should still have a few, of the competition Thermoquads for sale, that you can use for spare (and needed...???) parts, and maybe, do so, reasonably soon, just in case, the supply (of them), starts to dry up...…….Yours, might have, "press-in" jets (as opposed to, screw-in jets)..…….See if you can get ah-hold of, a Factory..."Chassis Service Manual"...for your exact car, because, that type of manual, will probably have, lots of information, about your Competition Thermoquad, along with, having, quite a few pictures of it, and, all of the adjustments required, as well as, the specifications for it, as well...……..Some time ago, I saw some, Mopar (Plymouth/Dodge, etc.), website "Forums", that had lots of information/discussions, about the Thermoquad carb, and maybe, there might be a guy or two, that have had, some on-hands experience, with the Competition model, of Thermoquad carb………..Good luck, and...….till next time...….Be Safe, take care, and have a good one.
I 've worked and raced 340 Demons since 1971. Yeah I'm 67 year's old. I still have a mint 340 Demon 4 speed. 14,200 original miles. The 71 Thermoquad doesn't have the o-rings. It's just like the Competition Series Thermoquad. It's 750 CFM vs the 850/1000. It uses the same screw in main jets as the Competition Series. 72 and up are the same . Good luck! They are great carbs!
Greetings...farmer7465...…….The following, should be of some help to you...…….I found two Thermoquad competition series model numbers for you...…....The first one, is a 4846-S, which should be an 850-cfm model, and, a 4847-S, which should be, a 1,000-cfm model (on most Thermoquads, these four numbers, followed by the letter S, are usually stamped into, the lowest part of the Thermoquad, at, one of the rear corners)...…...The Carter AFB carburetor, also, had a line of Competition Series carburetors too, so, watch out now, and, be aware of the differences...lol...…….Ur in luck, because, I saw an EBAY listing, for a "rebuild kit", for the 4800 Thermoquad competition series, and, the EBAY listing, is, as follows...........COMPETITION THERMOQUAD COMP SERIES 4 BBL CARBURETOR KIT 850 - 1000 CFM 4846S 4847S.........and, the seller's name on EBAY, is uscarburetors, and, is probably located in Chicago Illinois USA..........The price is $63.99 (US dollars...???)..........The instructions (paper type), are usually really good (the instructions, might be printed, by a company, named techlit...???...and, I still have, many of them, for different types of carbs, along with, the rebuild kit left-overs, that are still, in their original cardboard boxes too).........If Ya get one, don't lose that...instruction sheet...because, there are gonna be some, very, very good, settings/adjustments/specifications on it, as well as, the proper sequence of doing, said adjustments/settings..........If, Ya ever get around to, rebuilding your competition series TQ, then, if it happens to have those "nitrophyl" (looks, kinda-like, black plastic material) floats, then, put in a pair of new ones, because, I've had one of them, absorb gasoline, like a sponge, and then, it sank too low in the float bowl, and, the exhaust fumes, were through the roof...!!! (literally).........Brass floats, are a better bet, but, rarely, they might end up, having, a pin hole sized leak, or maybe, a faulty solder joint, which are usually, easily repaired, by soldering..........Lem-me-see-now........Old school...plus...paper instruction sheet...PRICELESS...!!!...lol...and......till next time......Be Safe, take care, and have a good one.
Yep, should have watched your video before the teardown! Missed the 2 hidden screws and was trying to pry everything apart! Wouldn't budge! Took out those 2 screws and it very easily came apart!
Greetings Tony....About the Carter Carburetor that you are wondering about....Perhaps just let me know here, in the comment section, then, if I can make a Video about the Carter Carb that you want to know some things about....I'm sure that I can show you much more in a Video, then just by talking about it....also, I have the ability to make drawings/sketches of just about anything on the Planet, as I have some Drafting ability too....Which Carburetor, and what Problems?....Take care my Friend.
Thank you for these videos, I have a similar carburetor on my 1974 Chrysler 440, maybe the same one. I am having issues with very hard starting when the car is cold. The car will start with my foot holding the gas but stalls three or 4 times until I can get enough fuel into it. It will start fine when the engine is warm, if I go into a store or something quickly and come back out. I tried adjusting the idle and fuel mixture screws which helped with idling and acceleration but not starting. I looked at the choke when the engine was cold and it is sitting half open, not closed like it should be. How do i adjust this? Thank you.
+Emerson ....Greetings Emerson....You're welcome, and, Thanks for watching..........Even if the Choke, and its related parts, are adjusted properly, and working as they should be, then, an Engine, that has a Carburetor on it, while also having, a good ole Mechanical type of Fuel Pump, bolted to the Engine block, will usually take even More Time/Engine Cranking, the More Days, that the Engine Sits, Not Running, and also, the Hotter, it happens to be, where the Vehicle is parked, with-out Running at all, as well...............Why You ask...???....well, Gasoline, that is sitting in the Carburetor's Float Bowl, will kinda evaporate, and that, my Friend, usually results in, the Float Bowl/s, having, Too Low of a Wet Fuel Level, or maybe, no Gasoline at all, and that's why, most of these old school Engines, require, quite a bit of Starter Motor Cranking, and that's, just so, the Mechanical Fuel Pump, can Pump enough Gasoline, into the Float Bowl/s, to feed that Cold Engine, the Richer Air/Fuel Ratio/Mixture, that it needs, until it gets up to Operating Temperature..................Now then, here's a Generic explanation, as to how, the Choke works, on the rather Basic, Thermoquad Carburetor, that You saw, in, all of these UA-cam Videos of mine....................If the Choke and its Linkages are adjusted properly, then, the following should take place.................On a Cold, and Not Running Engine, I would Press Down, on the Gas Pedal, and Release it (Foot Off)...............What, that just did (hopefully), would Close the Choke Plate, 100% Closed, and also, let that Big Heavy, Fast Idle Speed Screw, rise Up-wards, as far as it should go, onto a High Speed Step, of the Fast Idle Lever/cam...................Then, I try to Start The Engine, and when it Starts, (intake) Manifold Vacuum develops in the Engine, and actuates the Choke Pull-Off (that little Space Ship lookin' thing-ah-ma-Bob...lol), and, Pulls on the Linkage, causing the Choke Plate to Open, oh, about One Eighth of an Inch, to usually, no more, than about, One Quarter of an Inch (depending on that particular Carburetor's, Choke Break, or Vacuum Kick...[different words, meaning the same thing]...Specifications), which can be found in a Manufacturer's Chassis Manual, or, that particular Carburetor's, Rebuild Kit's, Instructions/paper/s...........Then, the Engine, will probably be, Revving quite High, in RPM's, and that's when, I give the Gas Pedal, a little Tap, and, when I did, that will let, that Trapped, Big Fast Idle Screw, Drop Down a bit, onto a Lower Speed Step, that's on that Fast Idle Lever/cam, and, will usually Lower the Engine RPM's, to a, not overly fast, and (hopefully) acceptable Engine speed..................As the Engine Warms-Up, the Thermostatic, Coiled-Up Choke Spring, that sits, just down inside, from the Top of the intake manifold, will start to Relax, and when it does, the Choke Plate will gradually start to Open, and that Big Fast Idle Screw, will start to Drop also, but, Only When, the Gas Pedal is Moving, other-wise, it gets Trapped, where-ever it happens to be Located, on that Fast Idle Lever/cam, and, the Engine will still be Revving kinda High, until the Gas Pedal starts Movin', so that Trapped Fast Idle Screw can Drop...!!!................Thermoquad Carburetors, can be kinda Tricky, when it comes to things, like Adjusting the Choke Linkages, cuz, that Choke Pull-Off, also Controls, that Bracket-like Thing, with the Curved Slot in it, that's responsible for, the Opening Rate, of the Secondary Air Door/Valve (just behind, where the Choke Plate is)...!!!...Yikes...!!!...........There is a Certain Sequence/Order of Doing Things, when it comes to, making, all of the Required Adjustments, and Setting-Up, of a Thermoquad Carburetor..............If some Adjustments are made "Out of Sequence", it will probably result in, one or more, of the Other Settings, being out of whack/not set-up right...!!!...just so You know..............Maybe, try the following, to determine, whether or not, Your Thermoquad's Choke is working reasonably well............After You have Driven Your Vehicle for the Day, let it sit over-night, then, Start Your Engine, the..."Very Next Day"...that way, there should still be enough Gasoline, inside, both of Your Thermoquad's Float Bowls, and if Your Vehicle Cold Starts Alright, using the Procedure, that I was tellin' You about, just above, then I'd say, Your Choke is probably Workin' OK, but, if not, then, that's when the Fun really Starts...lol.................If You care to, You can let me know, how Ur makin' out, and if need be, we should be able to figure it out (hopefully...lol), and...........till next time........Be Safe, take care, and have a good one.
Greetings aerial wheel....You are welcome, my Friend....Same 2 Hidden Screws can be found on a Rochester Dualjet (2 Barrel Carburetor), and a Rochester Quadrajet (4 Barrel carburetor) as well....I had read a while ago, that some Folks that didn't find those "2 Hidden Screws" on the Thermoquad that they were working on, probably tried to "Pry" that Poor Thermoquad Apart!...That resulted (as I have read), that the Phenolic Resin (plastic) Float Bowl gets "Warped" (bent), and then the "Excuse" that usually gets used, is that the Phenolic Resin Float Bowl "Warped" on its own!....To check out that Theory, all that one has to do, is take a look at the Top, and Bottom of that particular Thermoquads Phenolic Resin Float Bowl, and, Look for the Evidence, and that Evidence is, All of those "Pry Marks" left by the Tool (usually a Flat Tipped Screwdriver), that was used in an Attempt to Separate those "3" Thermoquad Sections (Air Horn, Float Bowl, and Throttle Body)....One might also find those Incriminating Pry Marks on the Bottom of the Aluminum Air Horn, or, on Top of the Throttle Body as well. When I was just starting out, I might have made that very same Mistake, only, I was very Fortunate, that I did indeed "Discover" (perhaps by looking at some drawings/pictures somewhere, if I recall correctly, that is), those "2 Hidden Screws", before I had to make that very same Claim, that My Thermoquads Float Bowl "Mysteriously" Warped on its Own!....Thank Goodness that I didn't have to Travel Down that Road!...lol...(but No lol, with the Damage that may have been caused by all of that Prying and Cursing!). As I see it, about the only way that a Thermoquads Phenolic Resin (plastic) Float Bowl can be "Warped" while still being Assembled as a "Sandwich" between the Air Horn (top aluminum casting), and the Throttle Body (bottom aluminum casting), is, if the Float Bowl becomes "Over-Heated" by various Sources....Perhaps, some of those sources might be, are, Excessive Back-Firing through the Thermoquad, or maybe a Carb (carburetor) Fire, or even a Fire that was in near proximity to the Thermoquad itself. Hmmmmm, I wonder if a Thermoquad Phenolic Resin (plastic) Float Bowl, might "Warp" somewhat, if it was just sitting on its Own (not Assembled as a complete Thermoquad Unit), out in the Hot Sun, on some Sand, and away from any Shade (shadow) that might be cast from a Cactus, or, Cacti (more then 1 Cactus) in the Dessert (oops, I meant DESERT!) as there is only 1 "S" in the word Desert!...(just thinking...). Well, there you have it, my 2-Cents Worth (or, maybe alot more, due to Inflation!...lol). If you require any Help or Advice from me at all, I should be around here somewhere (in Cyber-Space!...lol). Good luck with your Thermoquad. Take care, and have a good one.
Darn those "2" Hidden screws anyway!......Same "2" hidden screws can be found on 2 barrel Dualjet and 4 Barrel Quadrajet Rochester Carburetors as well!......Too bad that the Factory/Factories didn't stamp some warning "Arrows" on the choke plate pointing to those "2" Hidden "Critters" (screws)......Just imagine how many "Cuss" words were spoken when the Carb refused to separate!...lol...Just that the damage that may have been caused, is not so funny......Take care, and have a good one! (Today!)
Hey there, I have a car that originally came with this carb. but was replaced with an edlebrock, anyways after doing an engine rebuild and putting this carb. back on, there's a loss of power at high rpm. Any ideas?
Greetings SteFFy7469....Well now, I'll do what I can to help You out, but first, I need some clarification, as to just which Carburetor that You are having the "Loss of Power at High RPM's" issue with....Was it the Thermoquad, or, was it the Edelbrock Carburetor?....Also, I have no idea what-so-ever, as to what Engine that You have there, that was "Rebuilt?"....First thing that I need to know, is, are we talking about a Thermoquad, or an Edelbrock Carburetor?....In addition to the "Brand" of Carburetor, I will also need the "Model" of Carburetor, and the, shall we say, "Serial Number" of the Carburetor in question. If in fact, you intend to use the Thermoquad Carb, You can find the Identifying Number/Letter "Stamped" into the "Throttle Body" (aka, Bottom Aluminum Casting) on the "Left Rear, and Lowest Part" of Your Thermoquad Carb. You usually should be able to see "4 Numbers with the Letter S" at the end. In the case of the Edelbrock Carburetor, I'll need to know which one that we are talking about, as in...AFB, AVS, or perhaps, the newer offerings from the Edelbrock Folks. If indeed, You will be using the "Eddie" (aka, Edelbrock) Carburetor, it will surely help knowing which one that it happens to be, as well as the Model/Identifying Numbers and/or Letters that are located on the "Edelbrock" Carb. Also, which "Car" and "Year" does Your Car happen to be (I'm assuming that it just might be, a Chrysler, Dodge, or Plymouth perhaps), and, please describe Your Engine's Cubic Inch "Displacement" as in, 318, 340, 360, 383, 400, 440 V-8...or...is it a "Slant Six", as in 6 Cylinder Engine, which I happen to doubt, but, I have known stranger things to happen!...lol. Also, did You do a "Stock" Engine Rebuild, or did You "Modify" it in any way?" Any "Exhaust System Upgrades?" The reason I'm asking, is because, just by going from the "Original Cast Iron" Exhaust Manifolds to Tubular Exhaust "Headers", will usually cause almost any Carburetor to "Lean Out" somewhat, because of, what is known as, Exhaust Gas "Scavenging". This so called "Scavenging" that I'm talking about, causes an "Increase" in Exhaust Gas "Flow", and, from what I have experienced, was, my Spark Plugs were showing a somewhat "Whiter" Color, then they were, when I had the Stock "Cast Iron" Exhaust Manifolds on that there V-8 Engine. I was actually "Fore-Warned", by the Gentleman that sold me those "Exhaust Headers", as to the "Leaning Effect" that Exhaust Headers are known for. There are so many "Things" that can cause the "Symptom" that You were telling me about, and I'll list a few of them, that I've had some experience with... Gasoline these days, is so much different, from the Gasoline from way back when, and will usually cause just about any Carburetor to be running "Leaner", because of the "Ethanol" (aka, alcohol) being added to the "Gasoline Formulation", as well as additional "Stuff", like Oxygenates and Detergents, that are supposed to help with keeping the Fuel System "Clean". I have had, a "Brand New" Mechanical Fuel Pump, that I installed on a V-8 Engine, and, it turned out to be "Not Working" as it should, and the Carburetor was "Starving" for Gasoline! Also, Your Fuel "Filter/Filters" have to be "Clean", in order to prevent "Fuel Starvation!" Your Air Filter has to be very "Clean" as well, or Your Carburetor will probably be running "Rich" (aka, Air/Fuel" Ratio), and your Gas Mileage/Kilometer-age will be suffering as well. I have had to "Increase" my Thermoquads "Primary Jets" from .095" to .104" (95 Thousandths of an Inch, up to 104 Thousandths of an Inch), just to keep my Car from, what is called "Lean Surging" (aka, bucking back and forth) while just trying to maintain about 30 Miles per hour, or its Metric equivalent, being 50 Kilometers per hour, while holding the gas pedal in a fixed position, and on a level road. That my Friend, is how much of an effect that the "Newer" Formulations of Gasoline these days can "Alter" the "Air/Fuel" Ratio, and like I said earlier, Newer Formulations of Gasoline that we use these days, usually will cause just about any Carburetor out there, that was "Originally Calibrated" (aka, Air /Fuel Ratio) for the "Older" Gasoline, of about the Early 1970's and before that point in time. Then there is Your Ignition System's health, and how it's set up, in as far as, Initial Timing, Timing Advance, and Total Advance as well. Spark Plugs must be in good working order, as well as having the "Right" ones. So, there You have it, some "Food for Thought", well, for now that is. So, in order for me to be able to help You out any further, just let me know what I'm dealing with... ...or... ...I'll be going on another... ..."Wild Goose Chase!!!"...lol. Be Safe, take care, and have a good one.
RockysRoadshow Thank you for your quick response, you seem like real car guy. I appreciate you knowledge but do not intend to take up your time with a wild goose chase. I intend on working at getting this carb working this summer and figured there might be something obvious that I overloooked the first time. The car is a 1978 Dodge Aspen Super Coupe, a relatively rare car (531 produced). Originally with a 360ci police interceptor engine but rebuilt into a 408 stroker, larger cam stroker kit, ect. The rebuild has taken the engine from 200hp to about 390hp and 480ft lbs of torque. I am having trouble with the THERMOQUAD CARB (rebuilt). I do not have access to my specific carb at the moment however I know that it is approx. rated at 800 cfm. It's been nearly a year since I've had the thermoquad installed. I remember that this loss off power happened at about 4000-5000 rpm and mainly at WOT. At the lower rpms under WOT there is no hesitation and performs dramatically better than the eddlebrock, which I unfortunately can't get the model number of either at this moment. The car has had exhaust modifications, we have added hooker competition headers which go through 3.5 inch diameter side pipes. The air filter has been replaced, same with the fuel filters, have even tried a run with out some of the fuel filters. We have replaced the mechanical fuel pump for a higher pressure electric pump. Both larger and smaller jets have been tried to fix the issue, maybe a small (positive effect) from the largest jets but didn't solve the problem. The car is ran on about 94 octane gas. Ignition is from a mopar performance orange box and a mopar performance distributor. Spark plugs are quite new and should be in good condition. Thank you very much for your time but don't be too concerned with my carb problems, it's a project car and I have no problem working on it until it's fixed.
SteFFy7469 Greetings SteFFy7469....You are welcome, for that other Quick (Reply) Response, and, Thanks for providing me with most of your Car/Engine information, as, the more that I know about your "Ride", the more that I will be able to help You out, my Friend...and...please don't worry about taking up any of my time, because, "Cars, Trucks, and what makes Em Go" is a very "Major" Hobby of mine!....Let me start with some "Basics"....An Engine like Yours, "Needs"...Proper Ignition Timing...Proper Carburetor Air/Fuel Ratio, for all Engine Operating Conditions, at a "Flow Rate" that will support the demands of your "Modified" Engine, while at WOT and High RPM's...and...an Exhaust System that is able to "Flow" the amount of Exhaust Gas that comes out of Your Engine's "Heads" Exhaust Ports, without any "Exhaust Flow Restriction" especially at High RPM's while at Wide Open Throttle (aka, WOT). Now, let's do some "Eliminating", shall we... By what You said about Your Cars "Exhaust System", I can't see any problem with the "Exhaust Flow Rate" at Higher RPM's, but, You may have noticed, because of having virtually "No Exhaust Back-Pressure" with Your Exhaust System, that, Lower RPM's are a little weaker then, that, of what You may have had, with the "Cast Iron" Exhaust Manifolds installed on Your Engine. I thought that I would mention about the Weaker Lower RPM's Torque/Horsepower, just in case an issue or two arises, about Your Engines "Personality" while it is Running in the Lower RPM's Operating Range. Also, if the Camshaft that You have in Your "408-Stroker-V-8" is Reasonably "Aggressive" (and is usually accompanied by a "Lumpy Idle" as well), that You may have noticed that, You have to get the RPM's up a bit, before You really get going at all. I'll save many more Considerations that I have, for a later date. Now then, I'll state a few things on "Ignition Timing", and, save the "Carburetor Stuff" for last. In Your case of having problematic "Engine Operation" at about the "4000 to 5000" RPM Range, Your Distributor's "TOTAL" Timing has to be "Correct" for both Your "Engine", and The Fuel that You are putting in Your Gas Tank (I say that, just in case you put a different, or Lower "Octane" Gasoline in Your Gas Tank, which usually will require a Lower "Total Ignition Timing", to avoid Knocking and Pinging that could very well "Harm" Your Engine!). Your "TOTAL" Timing, in "Degrees" as measured at Your Engines Crankshaft, has to be, as they say, "ALL IN" Before Your Engine's RPM's reach Your Engines problematic "4000 to 5000" RPM's. (a "Ballpark Figure" would be around 34 Crankshaft Degrees (maybe a few Degrees "Less", and some People have found a few Degrees "More", works for them) Before Top Dead Center, but like I say, this is just a "Ballpark Figure!!!"), and, be "Very Careful" when having Your Engines "TOTAL" Ignition Timing Set, or Your Engine can be "Damaged, or even Destroyed", if You happen to "Over-Advance" Your Engine's "TOTAL" Ignition Timing! A Ball Park, "ALL IN" Ignition Timing of approx. "34" Degrees (Verify what "Your" Engine "Actually" Requires, for "ANY" of Its "Ignition Timing Needs!!!), might be, "ALL IN" by about "3000" RPM, and Your Engine might need a "Different" All In, as well as any "Other" Ignition Amount or Specification. "Total Timing" = is when you "ADD" the "Initial Timing", that is usually measured with a Timing Light, on the Crankshaft Damper/Timing Tab, while the Engine is at Idle Speed, to the 2 Advance Weights Maximum Timing Advance, when they hit their Stops. Before I go any further, there can be some "Confusing" matters that pertain to the following... ...make sure that You, or Anyone, are Fully Aware, that, there are "2-DIFFERENT" Degree Specifications!!!... "Crankshaft degrees, are just that, Degrees that are measured at the Crankshaft, or in other words...What You See, is, What You Get!...lol... ...where-as... ...when it come to "Distributor Degrees", then a Person "Has to Always Remember" that the Distributor "ONLY" Rotates at 1/2 (one half) the RPM's that the Crankshaft Rotates at!!! So, just pay very close attention to, if it happens to be "Distributor Degrees" or "Crankshaft Degrees", or, your Timing is going to be..."ALL MESSED UP!!!" Let's see what a Hypothetical "Total Advance" could be, with the following scenario, shall we... The Distributors Centrifugal Advance Weights have been set up for "24" Crankshaft Degrees (Not Distributor Degrees!), and, we set the "Initial" Timing at Idle speed, to "10" (Crankshaft) Degrees Before Top Dead Center. By Adding the "Initial" Timing to the Advance Timing of "24" (Crankshaft) Degrees, as provided by the Advance weights, we arrive at a "Total Advance" of "34" Degrees (at the Crankshaft)...and...with this "Total Advance", this is the Amount of Crankshaft Degrees that should be "ALL IN" at that "3000" Engine RPM, or whatever "Your" Engine "Likes", for an "ALL IN" RPM Specification. Please Note..."Do Not" Include the "Vacuum Advance" in Your "Total Timing", as, when You "Put-The-Pedal-To-The-Metal" (aka, "WOT"), the Intake Manifold Vacuum Level drops to almost "Zero!" (or, close to nothing at all). Check to see what Other People, and especially if they had their Engine on a "Dyno" (aka, Dynamometer), that have an "Engine like Yours", and are using a Gasoline "Octane Rating" comparable to Your "94" Octane, or "Lower Octane", if you have to go that route, due to the Pump Gas that is available in your Area. (unless, You happen to be adding some "Octane Booster" Concentrate to Your Cars Gas Tank, that is). As You can see, there are "So Many Variables" that can have an "Effect" on the way in which "Any" Gasoline Engine will "Run & Perform!" Now then, Lettuce (aka, Let Us...lol) move on to some of that Good Ole Thermoquad Carburetor Stuff, shall we? At this point in time, I'll just address a typical Thermoquad Carb, as well as, what Your particular "Model and Year" of Thermoquad, may be adding, in the way in which Your Engine is running, at that problematic "4000 to 5000" RPM Operating Range. Got your "Snack and Drink" yet... ..ok, I'll assume that..."All Systems are Go!"...lol. Seeing as how Your Thermoquad may very well be a "1978" Year/Model, I'm thinking that You have either an "800 CFM, or an "850" CFM (CFM = Cubic Feet per Minute Flow Rating). The "800" CFM Thermoquad usually has 1 3/8" (one and three eights of an inch) "Primary Throttle Plates" (aka, butterflies), and the "850" CFM Thermoquads usually have 1 1/2" (one and one half inch) Primary Throttle Plates. Even if You happen to have the "800" CFM Model of Thermoquad Carb, that should be, a "Large enough Flow Rate" for Your "408" while at "Redline", and at WOT, as well, as I see it. The added advantage with having the "Smaller Primaries" that are in the "800" CFM Thermoquad, is that, You will probably have a very "Crispy" (super responsive throttle, especially while driving around at City Speeds). Warning...If indeed Your Thermoquad Carb is a "1978" Model, I'm thinking that, it may very well be, "Calibrated" on the "Lean" side! (Lean = Less Fuel, in the Air/Fuel Ratio), and, that alone, will cause a High Performance Engine like Yours, to be "Acting Up". Hopefully, Your Thermoquad Carb, is Not a "Lean Burn" Model of Carburetor, because of the "Things", that they did to it, back then, not to mention the "Electronics" hidden in the "Thing-ah-mah-jig" that was mounted on the air cleaner housing. There are a few things, that I can think of, off hand, that You might want to do, or try, on Your Thermoquad Carb, and, if it actually "Is" Your Thermoquad causing that Running Problem at the 4000 to 5000 RPM Range, then, here Ya go... Firstly, Your "Choke Pull-off" has to be in "Like New" Condition, or, it "Won't Let the Secondary Air Valve Open Properly!"...and, the Secondary Air Valve will act "Just Like a Choke", and that will provide Your "408" with a..."Way Too Rich" Air/Fuel Ratio!" My advice...Install a "Brand New" Choke Pull-Off, or, You will be fighting a Losing Battle!...and...make sure, that You "Adjust" that New Choke Pull-Off, as per Specifications (there are some Custom Adjustments that can be made also). Now for Your Thermoquads Secondary Air Valve "Torsional" Spring (usually incorrectly called a Tension spring) "Adjustment!" Try Adjusting Your Secondary Air Valve Spring "Wind Up" (Wind Up = the Amount that You Adjust for, on Your Thermoquads Torsional or Tension spring that controls Your Secondary Air Door). I have a number of Videos (actually, Many!, or Lots!) of Stuff on the Thermoquad Carburetor, and one that Specifically Describes...How to "Adjust" the Secondary Air Valves "Torsional" Spring. Just type...RockysRoadshow...in the Search Box, at the Top of UA-cams Main Page...as that should show You a Listing of the 80 UA-cam Videos that I have made to date...Most of them are Automotive related...enjoy. Now, back to that Secondary Air Door "Spring" Adjustment....Just loosen off the screw threaded "Lock Ring" (it has 2 slots in it, and it surrounds the Adjustment "Screw"), then, loosen off the "Adjustment" Screw Slowly, until the Secondary Air Door Flops Open...Then, "Slowly", turn the Secondary Adjustment Screw in the "Tightening" Direction, until the Secondary Door starts coming back up, until it "Just Touches" the Air Horn Boss (aka, top aluminum casting), then, Slowly, turn it an "Additional" 1 1/2 Turns (one and one half turns) from when the Secondary Air Door just "Touched" that Upper Aluminum Casting Boss (Boss, is just a fancy word, for a protrusion)...and..."Don't" Forget to Tighten the "Threaded Locking Ring!!!" Please note...Make Sure that the Inner Screw "DOES NOT" Move or Spin, when You Tighten down the Locking Ring! (That so called Adjustment Screw, Isn't a Screw at all!...as...It Doesn't have any screw threads on it!). That 1 1/2 Turns Secondary "Torsional Spring Wind-Up" Amount, that I had just mentioned, is a very "Good" Starting Point to start at. I would also recommend..."NOT to go Past 2 or 3 Turns" on the Secondary Torsional Spring, as it happens to be telling me, that something "Just-Isn't-Right!", well, in as far as the Secondary Jetting, that is. I had a best result, setting me Secondary "Torsional Spring" Wind-Up....Set for 1 1/4 Turns, as, that's, what worked Best for me, at the time, and, I actually "Removed" the Choke Pull-Off Diaphragm, as I found out, that...I "DID NOT" Need it, due to having a 4-Speed Manual Transmission (You know, that there 3rd Pedal, just to the left of, that there brake pedal, also known as the...Clutch Pedal!...lol). Also, while I remember, my "850" CFM Thermoquad was on a 360 Cubic Inch V-8 (Factory High Performance Version), and it came from the Factory with .143" (one hundred and forty-three thousandths of an inch) "Secondary Jets" (aka BIG Ones!). See what "Secondary Jets" that are "Hiding" inside Your Thermoquad, and "Record" (aka, write it down), as I have seen some "Small" sized ones in the past. You might have to go to something like I had, You know, about .143" Secondary Jets, especially seeing as how you now have a "Gas Guzzler!...lol "ALL" Linkages and Adjustments on each, and every Thermoquad, have to be "Correct", and done in the Proper "Sequence", or, there'll be "Trouble-in-Paradise!" Thermoquads, like any of other of the Carburetors out there, will benefit from a "Fresh & Proper Rebuild". I just noticed that You Added a "HIGH PRESSURE" Fuel Pump!!! That my Friend, is a..."BIG NO-NO", when trying to supply a Thermoquad Carb with "TOO MUCH" Fuel Pressure!!! To me, a "HIGH VOLUME" Fuel Pump, might be OK...but... ...A "HIGH PRESSURE" Fuel Pump, that supplies any more then about "7" PSI (Pounds per square inch) to the Float System, will more then likely "OVER-POWER" the Floats "Ability", to "Apply" enough Force to the "Needles", that Need to be making Positive Contact to the "Seats" Orifice, or hole, if you will!... ...or, in simple terms...Any More, then about "7" PSI, will probably be "Forcing" Gasoline "Past" the Needles and Seats, as the "Floats" "ARE NOT" able to Apply enough Force to the "Needles", in order to "Seal-Off", that there "Very High Pressure Gasoline!!!" Just remember, no more then about "7" PSI Fuel Pressure, No-Matter How Fast (RPM's), or under what given load that the Engine may be subjected to! Also, Your Fuel Pump (be it Electric or mechanical) "Must" be able to supply Enough "Volume" (Not Pressure, as that is limited to about, no more then "7" PSI, or perhaps, just a little less). Make sure that Your Fuel Pump is able to keep Your Thermoquad's Float Bowls Filled-Up, especially at "WOT", where there will be...a "Very High Fuel Consumption Rate!" (Ball Park Fuel Pressure should be around 5 to 7 Pounds per square inch, and, if it falls way Too Low, You will probably be having a way Too Low "Wet Fuel Level" in both of Your Thermoquads Float Bowls!). I'm thinkin...Try and find the "Fuel Pressure" Specification for, perhaps a 440 Cubic Inch Engine, as the 440 will probably have similar "Fuel Pressure" Demands (and maybe Fuel Volume as well perhaps?), that will probably, at least, give You something to go by. Here's something else to consider, as to Your Thermoquads Calibration/Jetting... Gasoline, back in 1978 was a very "Different" Gasoline, as compared to the Gasoline that You put in Your Gas Tank These Days. I find that Today's Gasoline, Did make my Thermoquad Run quite a bit "Leaner" then when it was "Calibrated" for, as in, the good ole gas of the 70's. Warning...about those 2 (Black Plastic) "Nitrophyl" Floats, that I happen to think, that may be "Hiding" inside Your Thermoquad, are Known, to "Absorb" Gasoline", and over time, just might "Start to Sink", which will almost always cause an "Overly Rich" Air/Fuel Ratio, and, I actually "Saw", One of my Thermoquads "Primary Nozzles" (in the Primary throttle bores) actually "Dripping" Gasoline (as in..drip, drip, and even more drops of Gasoline), and that was when the Engine was Only at "Idle Speed!" In closing, and shall we say...Time to wrap it up... ...It's Very Important to Verify Your Engines "Total" Ignition Timing, as Ignition Timing can "Make or Break" Your Engine! (Literally!). Don't forget, there is actually "More" to Ignition Timing then You think, as in, everything, including..."Initial" Timing (aka, usually the amount of degrees Before Top Dead Center, as measured at the Crankshaft Harmonic Balancer, or Damper, if you will, and its position relative to having an "Accurate" Timing "Tab", that has been "Verified" on Your Engine), "Amount of Advance", and how quick it comes in, as well as the point, in RPM's where it just Starts to come in....also, "Vaccum Advance", that is usually a "Givin", on a Street Driven Vehicle, and used mostly for "Economy, and getting way better Gas Mileage/Kilometer-age" as well, when the Vehicle in question, is just "Cruising" along, and with having a very light Gas Pedal Applied as well. Seeing as how You probably have many $$$ Invested in Your "Limited Addition 1978 Dodge Aspen Super Coupe", and Your 408 Engine", I would Strongly "Recommend", that you go out and purchase an "Air/Fuel" Ratio Gauge Kit, that comes with a "Wide Band Oxygen Sensor", that will be able to "Display" Your Engine's Air/Fuel Ratio, while You Drive at different Speeds and Throttle (aka, Gas Pedal) Applications, that way, You'll "Know and See", just what Air/Fuel Ratio, that Your Thermoquad Carb is Feeding Your 408 Engine, while Your Engine is just "Idling", and, also, at all the Engine RPM's, while being under "Very Light Loads" while just Cruising along, up to, and including, a rather Heavy Load at "WOT" from a Standing Start! "Too Much" Ignition Advance is "Harmful" to almost any Engine!... ...and, If You happen to be Hearing any "Knocking" or "Pinging", that is a Sign to me, that, the Engine in question, is at "Risk", of having some "Very Expensive" and "Destructive" Engine Damage happening, as those "Sounds or Noises" are in effect! Same thing can be said about Running an Engine with a "Too Lean" Air/Fuel Ratio, as Running an Engine on a Too Lean Air/Fuel Ratio can and will, eventually Cause some very "Major" Engine Damage, that has been know to..."Drain the Bank Account", but only "If", You intend to "Repair" all of that Engine "Damage", that could have been "Avoided in the first place, so then, "Listen Carefully", that's if You can Hear anything Other then... ...Your (Maybe?)..."Loud" (Exhaust) "Side Pipes!!!"... ...I hope that some of the above, is able to help You out, to some degree... ...till next time... ...Be Safe, take care, and have a good one.
SteFFy7469 Greetings SteFFy7469....I did receive your Personal Message in my Inbox, and, Thank You, for your kind words....What I normally like to do, is to keep all Postings related to any of my UA-cam Videos, out in the open, so that the Public at Large may benefit from the dialog that is being discussed at any given time....I do however respect your need to keep it in a private domain, if that's what you desire....Now then, "On with the Show!"...lol....I watched your "408" Engine UA-cam Video, and, it sure sounded "Awesome!!!"....Congrats on Your D.I.Y. (Do It Yourself) 408 Engine installation in Your "Ride!"....Well done! Good to hear that Your Fuel Pressure is about right for Your Thermoquad Carb! Just remember to "Change Your Motor Oil" in Your 408 Engine reasonably soon, as there will probably be "Lots of Metal Bits and such" findings its way into Your Oil Pan, due to Your 408 Engine "Breaking itself in". Just think of the "Crosshatch" Pattern (Honing Finish in all 8 cylinder bores) in Your 408's Engine Block, and the Pistons Rings "Seating" themselves in, and scraping against those 8 Crosshatched Honed cylinder bores! Yes-Sir-ee-Bob, there is inevitably going to be all kinds of metal bits, and then some, and there is no stopping that, when a "New" or "Rebuilt" Engine gets started and running for the first time! From what I recall, just about every "New or Rebuilt" mechanical part, such as Rear Axle Ring and Pinion Gears, Engines, Transmissions, Bearings, etc., need to be "Broken-In" for about at least 500 Miles. So before You start "Racing Your Ride", Take it Easy for the First 500 Miles or so, in order to let any, and all "New or Rebuilt Parts", Wear In, Seat, or even call it, Parts Conditioning if you like, because, once those New or Rebuilt Parts are "Broken In Properly", each of those Parts "Will" be Lasting Much, Much Longer!...But Racing, well, that's a whole "Different Story!"...lol. I suggest that You Start and Run Your Engine at least Once-ah-Month, and the More, the Better! Why You ask?... Here's why...I had a Flat Tappet/Hydraulic Lifter Camshaft's Exhaust Lobe "Disintegrate" on a Chevy 350 Cubic Inch V-8. Also, had a 2-Piece Rear Crankshaft Seal, on a different V-8, Dry-Out and start "Leaking"... ...and, if you leave an Engine sitting "Dormant" for a very long time, there are Engines that get "Seized-Up" due to the Pistons and Piston Rings Corroding/Bonding to the Engine Blocks Cylinder Bores!... ...I figure that, the Above "Ugly-ness", was due to "Not Starting and Running the Engine Often Enough, and getting that Motor Oil Circulating, to Lubricate the Engines Internal Parts!!!" So then, especially if Your Engine has Flat Lifters, either Mechanical or Hydraulic Type, then, I "Strongly" Suggest that You Start and Run Your Engine Up-To Operating Temperature, No-Less the "Once-ah-Month", to avoid some, Down-Right Expensive and Not Appreciated Engine "Damage!!!" I'll add this here...If Your 408 Engine Does Have a Flat Tappet/Lifter Camshaft in it, perhaps, try to find some Motor Oil with some "Zink" in it (I think that's what some experienced Guys were speaking of, a while back) in order to ensure that Your Camshaft and Tappets/Lifters, get the Proper Lubrication and Protection, as, most of the "Newer" Motor Oil Manufacturers/Producers have taken out, most, if not all of the "Zink" that use to be in the Older Motor Oils, way back when. If in fact, You Do have a Roller Camshaft, and Roller Lifters in Your 408, then, it will be way more forgiving, in as far as the Camshaft Lobe "Destruction" scenario is concerned. Always Remember, that, "ENGINE EXHAUST FUMES ARE DEADLY!!!"...so, MAKE SURE, that You Have LOTS OF FRESH AIR AND VENTILATION, as in, KEEP THE BIG GARAGE DOOR FULLY OPEN whenever Your ENGINE IS RUNNING!!! Here is one More "Disaster" that You can also avoid, as it relates to a Vehicle's Parking/Emergency Brake, while the Vehicle in Extended Storage. Here's what happened to me... ...I had a Car, parked in my garage for a few years, and, when it came time to move it out-ah-there, my Rear Brakes (Drum Brakes) were "Locked Up Solid!!!" Hmmmmm, why is that, I was thinkin... ...I came to the conclusion that, the Rear Brake Shoes actually "Bonded" to the Brake Drums!!!" Damn Car was parked up tight on one side, very close to the garage side wall, so, I had to put a hydraulic jack under the rear axle, and drag the car sideways, so I could get at the wheel and brake drum that was so very close to that garages side wall... ...Man, not something that I ever want to do on a regular basis, that's for damn sure! So then, if You have Drum Brakes on Your Car, You can avoid the "Brake Shoes Bonding to the Brake Drums" Scenario, by just leaving the Emergency/Parking Brake "Off", but be Warned, Your Vehicle should be on Level Ground, Transmission in Park or 1st gear if it's a Standard Transmission, and all 4 Tires must have Tire Chalks (aka, Bricks, Lumber, etc.), to keep the Vehicle from Rolling away, and possibly Injuring Someone, or, crashing into something as well!!! That's all for the time being... ...Be Safe, take care, and have a good one.
I've got one that was sitting inside my 70 charger when it was retrieved. but its froze up solid. looks like it had been sitting in water. I'll do a video on it tomorrow and put it on my page.
+Aziz Lamar Greetings Aziz Lamar....Thanks for watching........................Here's what I would do, if it were me, having the Carb, that You were just talkin' about...............I would Carefully, Remove all of the Screws, and, Carefully, Take "it" Apart.......................Then, Clean it all up.........................Then, by taking a close look at "it", that, in itself, would probably be tellin' me, whether, it was, or was not, "Rebuildable", to the point of, having this particular Carb "Working Properly", and as it should be doing...................In the event, that this particular Carb, was "Too Far Gone", then, a good place to start looking for, the "Exact Same Carb", would be on...E-Bay..................................Some, might be almost New Looking, or Rebuilt (properly, I hope), and, the Price of them, is usually, not all that bad, as well, most of the time....................................Make sure that, You Record/Write Down, the, usually..."4 Numbers, with the Letter S at the end", of those 4 Numbers, that You should be able to see..."Stamped Into"...the..."Lowest, Left Rear Corner"...(as Viewed, from the Back), of Your Thermoquad Carburetor............................Use those..."4 Numbers, with the Letter S at the end"...when-ever You happen to be Ordering any "Parts" for that "Exact Thermoquad" Carb, to be sure, that, You get the Correct Parts for it....................Well......till next time.............Be Safe, take care, and have a good one.
RockysRoadshow thanks. I'm about to shoot a video of it and upload it onto my page. Its should be there in the next 15 to 20 minutes so you can get a glimpse of the problem. Thanks again for the advice.
RockysRoadshow all right sir I've put the video on my page by the title of "The thermoquad. Rebuild?'' on my page. You can redirect to your UA-cam page click the blue person by my name and it should lead you straight to it so you can give me your opinion on can it be rebuilt or not. Thanks.
+Aziz Lamar Greetings Aziz Lamar...I watched Your Thermoquad, UA-cam Video, and, it sure looks like it has seen better days alright............................All of that corrosion-like stuff on the Thermoquad's Aluminum, top and bottom Castings, as well as the rust, that is seen, on the Steel parts, at times, can be caused, by being Stored, in a some-what, Cold, and High Humidity (lots of moisture in the air)...environment, for quite a long time...................I saw that, someone, in the past, Bent some of those rod-like Linkages, in about, the middle of them......................Perhaps, put some Penetrating Oil, on all of the Screw's...screw-threads, to dissolve, some of that corrosion-like stuff, that usually takes place, when-ever Steel (the Screws), are in contact, with the Thermoquad's, Aluminum Castings, so, the Steel Screws, Don't Rip-out, the Aluminum Screw-threads, while trying to remove them, oh and..."Don't Forget about the 2 HIDDEN Screws"...that are Hiding Under the Choke Plate...!!!.................................Also, put some of that Penetrating Oil, on all of the "Moving Parts" as well, in order to have them Move Freely, once again...hopefully................................If and when-ever, You get Your Thermoquad apart, You will be able to actually see, just how good, or bad, the Inside of it looks, that's for sure......................................Even "If"...???...You actually do, rebuild Your Thermoquad carb, there's going to be some Money needed, for some "New Parts", and are as follows......................I Usually Purchase and Install........the Exact Rebuild Kit.......2 New Floats (the Brass ones)......and.....a New Choke Pull-Off (that be that little space ship lookin' thing...lol), so the Thermoquad will work properly, once all of the Adjustments/Set-up, are done, in the Exact, Specified Sequence/Order, according to the Rebuild Kit Instructions, and/or, a Factory Service Manual, if one is available, that is.................................You are looking at, about $100 Canadian Dollars (retail) or more, just for the few parts that I just mentioned..............................Once You find out, what those..."4 Numbers, followed by the Letter S"...are, do an Internet Search for...Vaanths Thermoquad Guide...or just...Vaanths Guide...and, once You find it, there is LOTS of Information, about so Many of the Thermoquad carburetors, that were built over the years...................You can Look-up, just about any Thermoquad, using those..."4 Numbers, with the S at the end"...and, most of the Specifications, will probably include, things, like, Primary and Secondary Fuel/Jet Sizes, as well as, the Step/Sizes, for the Metering Rods as well.........................Check Your Thermoquad's, Primary Throttle Bores/front ones, to see if, they are...1 and 3/8 inch Diameter (800 CFM/Cubic Feet per minute, Air/Fuel, Flow Rating) or, 1 and 1/2 Inch Diameter (850 CFM)..........Vaanths Thermoquad Guide, will probably show You, just What, Year and Engine Size, that those 4 Numbers, followed by, the letter S", that's found on, just about any Thermoquad, was Originally Installed On, right from the Factory, when brand new......................So, if and when, You might, Open Up Your Thermoquad, perhaps, make a UA-cam Video of it, so I'll be able to see, what's happenin', inside of it as well...thanks.......Till next time..............Be Safe, take care, and have a good one.
RockysRoadshow OK thanks for this good advice on the thermoquad. You've been very very helpful. Moneys a little dry right now. It might be some months or so but when I do tear open the thermoquad I will do another video and mention you again and show the thermoquads insides. Thanks again for your help,advice,and thermoquad videos. I'll hit your subscribe button. Thanks again
Thanks for the nice comment!......Sorry for the late reply......More TQ videos on the way......Take care my Friend.
Greetings Bossman........Actually there are Two "O" Rings, and sometimes they get "Stuck" in the bottom of the Phenolic Resin Float Bowl.......Use a Flashlight...(make sure that there is Not any Gas or Gas Fumes in your Float Bowl).....and look carefully and see if they are Stuck at the bottom.....In the earlier ones, they used to have Leather or some kind of Gasket material that got really dried up, especially if the engine hasn't been running for a long time.....No "O" Rings = "BIG LEAK!"
Very informative, thanks so much for taking the time to make the videos.
Like they threw it like a FOOTBALL
HAHAHA
Thank you for uploading your videos on the thermoquad, having an american car in the uk most people dont know what a 4 barrel is let alone one that is as …. special … as this one.
Gave you a like and subscribed
Greetings...Chris Nichols...........You're welcome, and, thanks for watching, oh, and, thanks for the "like" too...........Lem-me-see-now...hmmm...an American car, on the U.K.'s motorways...??? (I think that's what they might be called?), as in, damn, the..."steering wheel"...is on the "wrong side" of the car...!!!...lol...........If a Thermoquad carburetor, is calibrated properly (jets & metering rods, etc.), and, is also set up correctly, then, it's usually known, that, it'll perform like a beast, well, at least, it usually does for me, on a good day that is............For starters, make sure, that, the two "floats", are in good shape, and are floating, in/on top of the gasoline, in the two float bowls "correctly", as in, sometimes, the nitrophyl, type of float material (looks, kinda like black plastic), can sometimes, over time (years usually), start to act like a "sponge", and start to absorb gasoline (petrol), and then, the "wet" fuel level, in the float bowl/s, will usually become too high, and then, a richer then wanted, air/fuel ratio will be the result (as in, maybe, carbon fouled spark plugs, as well as, poor fuel economy), oh, and, same result can happen, with (hollow) brass floats as well, when-ever a pinhole sized leak, in the brass, or, even in the solder, that secures, both halves, of the (hollow) brass float together, takes place...........If you haven't already done so, do an internet search for...Vaanths Thermoquad Guide...(I hope, that I got it right), and, hopefully, a few of the websites out there, will have a link to it, and, once there, there is lots, did I say Lots, of Thermoquad carburetor information, to be had, and then some............The gentleman that wrote it, did a fantastic job, to say the least...........Enjoy your American ride, in the U.K., even if, some folks, give you funny looks...lol...and........till next time.......Be Safe, take care (watch those "speeding tickets"...lol), and have a good one.
I watched all your videos. all are great and informative. One thing baffles me. I have a 1971 carb off my 1971 duster340. Air horn inside is nothing like what I am seeing here. Have rebuilt it several times in the last 50 years. Still can't find the o rings you talk about. Car runs good as it did in 1971.
Greetings...farmer7465...…….Thanks for the nice comment, and for, watching too...……The proper "rebuild kit", for your "exact" carburetor model number, will hopefully have, the "O" or "X" rings in it (the model number, is usually "stamped into", the lowest part of the Thermoquad carb, at one of the rear corners, and, is usually..."four numbers, followed by the letter "S")…("don't use", the numbers/letters, that are cast into the top of the carb...!!!)……….Those two "O" rings, might be stuck, at the bottom of, the (phenolic resin/black center section's) cavity/s, where the two, (top of the carburetor's), aluminum, fairly long, downwards/protruding parts, fit into (yes, they can get stuck, and be "hiding", so, shine a bright flashlight, down in there, in order to see, if they are in there, or not)………...Check out...Vaanths Thermoquad Guide...on the internet, who's "link", will hopefully, still be posted on some websites...……..The Thermoquad information is very good, and, the guy that wrote/compiled it, did a super job, to say the least...……..Those 340's, had a really good reputation, back in the day...…….The 360, was the engine that replaced it, but smog/emissions, lowered the compression ratio, along with, some of its power output too, but, in 1974, it still had, 245 Horsepower, and, 320 Foot Pounds of Torque (please note, that, in about 1972, they changed, the..."actual"...engine's Horsepower and Torque, to the "Net" system, which is much lower, than, the rating system, that, your 340 was probably rated with)……….."Net" horsepower and torque, as far as I recall, was, by having, most of the engine's, external components, hooked up and operating, and maybe, with some drivetrain losses, thrown in there as well, maybe...I'll have to look it up, sometime)………..Many moons ago, a Chrysler dealership, parts, counter guy, told me that, that, 245 "net" horsepower, would probably be, about 285 Horsepower, as I recall...…….Your 340, is definitely a "Keeper", so..."Keep it"...lol...…...Enjoy Ur ride, and......till next time......Be Safe, take care, and have a good one.
@@RockysRoadshow As I say, my 1971 4972s is nothing like the later thermoquads. The competition series and the 1971's are air metered. Many differences inside. The resin bowl is all together different. No o-Rings. I have not yet run across a video on this. If you can, get a hold of one of these carbs, and check the differences. I have pictures, but can't figure how to send them to you. I am old school, got left behind in the cyber circle.
Greetings...farmer7465...……..Now that you mention it, I do recall hearing about, the air-metered version of the Thermoquad, a long time ago...……..If you ever need any parts for it, then, E-Bay, should still have a few, of the competition Thermoquads for sale, that you can use for spare (and needed...???) parts, and maybe, do so, reasonably soon, just in case, the supply (of them), starts to dry up...…….Yours, might have, "press-in" jets (as opposed to, screw-in jets)..…….See if you can get ah-hold of, a Factory..."Chassis Service Manual"...for your exact car, because, that type of manual, will probably have, lots of information, about your Competition Thermoquad, along with, having, quite a few pictures of it, and, all of the adjustments required, as well as, the specifications for it, as well...……..Some time ago, I saw some, Mopar (Plymouth/Dodge, etc.), website "Forums", that had lots of information/discussions, about the Thermoquad carb, and maybe, there might be a guy or two, that have had, some on-hands experience, with the Competition model, of Thermoquad carb………..Good luck, and...….till next time...….Be Safe, take care, and have a good one.
I 've worked and raced 340 Demons since 1971. Yeah I'm 67 year's old. I still have a mint 340 Demon 4 speed. 14,200 original miles. The 71 Thermoquad doesn't have the o-rings. It's just like the Competition Series Thermoquad. It's 750 CFM vs the 850/1000. It uses the same screw in main jets as the Competition Series. 72 and up are the same . Good luck! They are great carbs!
Greetings...farmer7465...…….The following, should be of some help to you...…….I found two Thermoquad competition series model numbers for you...…....The first one, is a 4846-S, which should be an 850-cfm model, and, a 4847-S, which should be, a 1,000-cfm model (on most Thermoquads, these four numbers, followed by the letter S, are usually stamped into, the lowest part of the Thermoquad, at, one of the rear corners)...…...The Carter AFB carburetor, also, had a line of Competition Series carburetors too, so, watch out now, and, be aware of the differences...lol...…….Ur in luck, because, I saw an EBAY listing, for a "rebuild kit", for the 4800 Thermoquad competition series, and, the EBAY listing, is, as follows...........COMPETITION THERMOQUAD COMP SERIES 4 BBL CARBURETOR KIT 850 - 1000 CFM 4846S 4847S.........and, the seller's name on EBAY, is uscarburetors, and, is probably located in Chicago Illinois USA..........The price is $63.99 (US dollars...???)..........The instructions (paper type), are usually really good (the instructions, might be printed, by a company, named techlit...???...and, I still have, many of them, for different types of carbs, along with, the rebuild kit left-overs, that are still, in their original cardboard boxes too).........If Ya get one, don't lose that...instruction sheet...because, there are gonna be some, very, very good, settings/adjustments/specifications on it, as well as, the proper sequence of doing, said adjustments/settings..........If, Ya ever get around to, rebuilding your competition series TQ, then, if it happens to have those "nitrophyl" (looks, kinda-like, black plastic material) floats, then, put in a pair of new ones, because, I've had one of them, absorb gasoline, like a sponge, and then, it sank too low in the float bowl, and, the exhaust fumes, were through the roof...!!! (literally).........Brass floats, are a better bet, but, rarely, they might end up, having, a pin hole sized leak, or maybe, a faulty solder joint, which are usually, easily repaired, by soldering..........Lem-me-see-now........Old school...plus...paper instruction sheet...PRICELESS...!!!...lol...and......till next time......Be Safe, take care, and have a good one.
Yep, should have watched your video before the teardown! Missed the 2 hidden screws and was trying to pry everything apart! Wouldn't budge! Took out those 2 screws and it very easily came apart!
Greetings Tony....About the Carter Carburetor that you are wondering about....Perhaps just let me know here, in the comment section, then, if I can make a Video about the Carter Carb that you want to know some things about....I'm sure that I can show you much more in a Video, then just by talking about it....also, I have the ability to make drawings/sketches of just about anything on the Planet, as I have some Drafting ability too....Which Carburetor, and what Problems?....Take care my Friend.
Thank you for these videos, I have a similar carburetor on my 1974 Chrysler 440, maybe the same one. I am having issues with very hard starting when the car is cold. The car will start with my foot holding the gas but stalls three or 4 times until I can get enough fuel into it. It will start fine when the engine is warm, if I go into a store or something quickly and come back out. I tried adjusting the idle and fuel mixture screws which helped with idling and acceleration but not starting. I looked at the choke when the engine was cold and it is sitting half open, not closed like it should be. How do i adjust this? Thank you.
+Emerson ....Greetings Emerson....You're welcome, and, Thanks for watching..........Even if the Choke, and its related parts, are adjusted properly, and working as they should be, then, an Engine, that has a Carburetor on it, while also having, a good ole Mechanical type of Fuel Pump, bolted to the Engine block, will usually take even More Time/Engine Cranking, the More Days, that the Engine Sits, Not Running, and also, the Hotter, it happens to be, where the Vehicle is parked, with-out Running at all, as well...............Why You ask...???....well, Gasoline, that is sitting in the Carburetor's Float Bowl, will kinda evaporate, and that, my Friend, usually results in, the Float Bowl/s, having, Too Low of a Wet Fuel Level, or maybe, no Gasoline at all, and that's why, most of these old school Engines, require, quite a bit of Starter Motor Cranking, and that's, just so, the Mechanical Fuel Pump, can Pump enough Gasoline, into the Float Bowl/s, to feed that Cold Engine, the Richer Air/Fuel Ratio/Mixture, that it needs, until it gets up to Operating Temperature..................Now then, here's a Generic explanation, as to how, the Choke works, on the rather Basic, Thermoquad Carburetor, that You saw, in, all of these UA-cam Videos of mine....................If the Choke and its Linkages are adjusted properly, then, the following should take place.................On a Cold, and Not Running Engine, I would Press Down, on the Gas Pedal, and Release it (Foot Off)...............What, that just did (hopefully), would Close the Choke Plate, 100% Closed, and also, let that Big Heavy, Fast Idle Speed Screw, rise Up-wards, as far as it should go, onto a High Speed Step, of the Fast Idle Lever/cam...................Then, I try to Start The Engine, and when it Starts, (intake) Manifold Vacuum develops in the Engine, and actuates the Choke Pull-Off (that little Space Ship lookin' thing-ah-ma-Bob...lol), and, Pulls on the Linkage, causing the Choke Plate to Open, oh, about One Eighth of an Inch, to usually, no more, than about, One Quarter of an Inch (depending on that particular Carburetor's, Choke Break, or Vacuum Kick...[different words, meaning the same thing]...Specifications), which can be found in a Manufacturer's Chassis Manual, or, that particular Carburetor's, Rebuild Kit's, Instructions/paper/s...........Then, the Engine, will probably be, Revving quite High, in RPM's, and that's when, I give the Gas Pedal, a little Tap, and, when I did, that will let, that Trapped, Big Fast Idle Screw, Drop Down a bit, onto a Lower Speed Step, that's on that Fast Idle Lever/cam, and, will usually Lower the Engine RPM's, to a, not overly fast, and (hopefully) acceptable Engine speed..................As the Engine Warms-Up, the Thermostatic, Coiled-Up Choke Spring, that sits, just down inside, from the Top of the intake manifold, will start to Relax, and when it does, the Choke Plate will gradually start to Open, and that Big Fast Idle Screw, will start to Drop also, but, Only When, the Gas Pedal is Moving, other-wise, it gets Trapped, where-ever it happens to be Located, on that Fast Idle Lever/cam, and, the Engine will still be Revving kinda High, until the Gas Pedal starts Movin', so that Trapped Fast Idle Screw can Drop...!!!................Thermoquad Carburetors, can be kinda Tricky, when it comes to things, like Adjusting the Choke Linkages, cuz, that Choke Pull-Off, also Controls, that Bracket-like Thing, with the Curved Slot in it, that's responsible for, the Opening Rate, of the Secondary Air Door/Valve (just behind, where the Choke Plate is)...!!!...Yikes...!!!...........There is a Certain Sequence/Order of Doing Things, when it comes to, making, all of the Required Adjustments, and Setting-Up, of a Thermoquad Carburetor..............If some Adjustments are made "Out of Sequence", it will probably result in, one or more, of the Other Settings, being out of whack/not set-up right...!!!...just so You know..............Maybe, try the following, to determine, whether or not, Your Thermoquad's Choke is working reasonably well............After You have Driven Your Vehicle for the Day, let it sit over-night, then, Start Your Engine, the..."Very Next Day"...that way, there should still be enough Gasoline, inside, both of Your Thermoquad's Float Bowls, and if Your Vehicle Cold Starts Alright, using the Procedure, that I was tellin' You about, just above, then I'd say, Your Choke is probably Workin' OK, but, if not, then, that's when the Fun really Starts...lol.................If You care to, You can let me know, how Ur makin' out, and if need be, we should be able to figure it out (hopefully...lol), and...........till next time........Be Safe, take care, and have a good one.
i never found that little o ring @4:40 inside my thermoquad when i took it apart it ran fine on my car beforehand though. were could i find one?
Where did you find a carb for 25
THANK YOU!!!! this is why i always ask someone who has already done it. HIDDEN SCREWS!!!
Greetings aerial wheel....You are welcome, my Friend....Same 2 Hidden Screws can be found on a Rochester Dualjet (2 Barrel Carburetor), and a Rochester Quadrajet (4 Barrel carburetor) as well....I had read a while ago, that some Folks that didn't find those "2 Hidden Screws" on the Thermoquad that they were working on, probably tried to "Pry" that Poor Thermoquad Apart!...That resulted (as I have read), that the Phenolic Resin (plastic) Float Bowl gets "Warped" (bent), and then the "Excuse" that usually gets used, is that the Phenolic Resin Float Bowl "Warped" on its own!....To check out that Theory, all that one has to do, is take a look at the Top, and Bottom of that particular Thermoquads Phenolic Resin Float Bowl, and, Look for the Evidence, and that Evidence is, All of those "Pry Marks" left by the Tool (usually a Flat Tipped Screwdriver), that was used in an Attempt to Separate those "3" Thermoquad Sections (Air Horn, Float Bowl, and Throttle Body)....One might also find those Incriminating Pry Marks on the Bottom of the Aluminum Air Horn, or, on Top of the Throttle Body as well.
When I was just starting out, I might have made that very same Mistake, only, I was very Fortunate, that I did indeed "Discover" (perhaps by looking at some drawings/pictures somewhere, if I recall correctly, that is), those "2 Hidden Screws", before I had to make that very same Claim, that My Thermoquads Float Bowl "Mysteriously" Warped on its Own!....Thank Goodness that I didn't have to Travel Down that Road!...lol...(but No lol, with the Damage that may have been caused by all of that Prying and Cursing!).
As I see it, about the only way that a Thermoquads Phenolic Resin (plastic) Float Bowl can be "Warped" while still being Assembled as a "Sandwich" between the Air Horn (top aluminum casting), and the Throttle Body (bottom aluminum casting), is, if the Float Bowl becomes "Over-Heated" by various Sources....Perhaps, some of those sources might be, are, Excessive Back-Firing through the Thermoquad, or maybe a Carb (carburetor) Fire, or even a Fire that was in near proximity to the Thermoquad itself.
Hmmmmm, I wonder if a Thermoquad Phenolic Resin (plastic) Float Bowl, might "Warp" somewhat, if it was just sitting on its Own (not Assembled as a complete Thermoquad Unit), out in the Hot Sun, on some Sand, and away from any Shade (shadow) that might be cast from a Cactus, or, Cacti (more then 1 Cactus) in the Dessert (oops, I meant DESERT!) as there is only 1 "S" in the word Desert!...(just thinking...).
Well, there you have it, my 2-Cents Worth (or, maybe alot more, due to Inflation!...lol).
If you require any Help or Advice from me at all, I should be around here somewhere (in Cyber-Space!...lol).
Good luck with your Thermoquad.
Take care, and have a good one.
Darn those "2" Hidden screws anyway!......Same "2" hidden screws can be found on 2 barrel Dualjet and 4 Barrel Quadrajet Rochester Carburetors as well!......Too bad that the Factory/Factories didn't stamp some warning "Arrows" on the choke plate pointing to those "2" Hidden "Critters" (screws)......Just imagine how many "Cuss" words were spoken when the Carb refused to separate!...lol...Just that the damage that may have been caused, is not so funny......Take care, and have a good one! (Today!)
Hey there, I have a car that originally came with this carb. but was replaced with an edlebrock, anyways after doing an engine rebuild and putting this carb. back on, there's a loss of power at high rpm. Any ideas?
Greetings SteFFy7469....Well now, I'll do what I can to help You out, but first, I need some clarification, as to just which Carburetor that You are having the "Loss of Power at High RPM's" issue with....Was it the Thermoquad, or, was it the Edelbrock Carburetor?....Also, I have no idea what-so-ever, as to what Engine that You have there, that was "Rebuilt?"....First thing that I need to know, is, are we talking about a Thermoquad, or an Edelbrock Carburetor?....In addition to the "Brand" of Carburetor, I will also need the "Model" of Carburetor, and the, shall we say, "Serial Number" of the Carburetor in question.
If in fact, you intend to use the Thermoquad Carb, You can find the Identifying Number/Letter "Stamped" into the "Throttle Body" (aka, Bottom Aluminum Casting) on the "Left Rear, and Lowest Part" of Your Thermoquad Carb.
You usually should be able to see "4 Numbers with the Letter S" at the end.
In the case of the Edelbrock Carburetor, I'll need to know which one that we are talking about, as in...AFB, AVS, or perhaps, the newer offerings from the Edelbrock Folks.
If indeed, You will be using the "Eddie" (aka, Edelbrock) Carburetor, it will surely help knowing which one that it happens to be, as well as the Model/Identifying Numbers and/or Letters that are located on the "Edelbrock" Carb.
Also, which "Car" and "Year" does Your Car happen to be (I'm assuming that it just might be, a Chrysler, Dodge, or Plymouth perhaps), and, please describe Your Engine's Cubic Inch "Displacement" as in, 318, 340, 360, 383, 400, 440 V-8...or...is it a "Slant Six", as in 6 Cylinder Engine, which I happen to doubt, but, I have known stranger things to happen!...lol.
Also, did You do a "Stock" Engine Rebuild, or did You "Modify" it in any way?"
Any "Exhaust System Upgrades?"
The reason I'm asking, is because, just by going from the "Original Cast Iron" Exhaust Manifolds to Tubular Exhaust "Headers", will usually cause almost any
Carburetor to "Lean Out" somewhat, because of, what is known as, Exhaust Gas "Scavenging".
This so called "Scavenging" that I'm talking about, causes an "Increase" in Exhaust Gas "Flow", and, from what I have experienced, was, my Spark Plugs were showing a somewhat "Whiter" Color, then they were, when I had the Stock "Cast Iron" Exhaust Manifolds on that there V-8 Engine.
I was actually "Fore-Warned", by the Gentleman that sold me those "Exhaust Headers", as to the "Leaning Effect" that Exhaust Headers are known for.
There are so many "Things" that can cause the "Symptom" that You were telling me about, and I'll list a few of them, that I've had some experience with...
Gasoline these days, is so much different, from the Gasoline from way back when, and will usually cause just about any Carburetor to be running "Leaner", because of the "Ethanol" (aka, alcohol) being added to the "Gasoline Formulation", as well as additional "Stuff", like Oxygenates and Detergents, that are supposed to help with keeping the Fuel System "Clean".
I have had, a "Brand New" Mechanical Fuel Pump, that I installed on a V-8 Engine, and, it turned out to be "Not Working" as it should, and the Carburetor was "Starving" for Gasoline!
Also, Your Fuel "Filter/Filters" have to be "Clean", in order to prevent "Fuel Starvation!"
Your Air Filter has to be very "Clean" as well, or Your Carburetor will probably be running "Rich" (aka, Air/Fuel" Ratio), and your Gas Mileage/Kilometer-age will be suffering as well.
I have had to "Increase" my Thermoquads "Primary Jets" from .095" to .104" (95 Thousandths of an Inch, up to 104 Thousandths of an Inch), just to keep my Car from, what is called "Lean Surging" (aka, bucking back and forth) while just trying to maintain about 30 Miles per hour, or its Metric equivalent, being 50 Kilometers per hour, while holding the gas pedal in a fixed position, and on a level road.
That my Friend, is how much of an effect that the "Newer" Formulations of Gasoline these days can "Alter" the "Air/Fuel" Ratio, and like I said earlier, Newer Formulations of Gasoline that we use these days, usually will cause just about any Carburetor out there, that was "Originally Calibrated" (aka, Air /Fuel Ratio) for the "Older" Gasoline, of about the Early 1970's and before that point in time.
Then there is Your Ignition System's health, and how it's set up, in as far as, Initial Timing, Timing Advance, and Total Advance as well.
Spark Plugs must be in good working order, as well as having the "Right" ones.
So, there You have it, some "Food for Thought", well, for now that is.
So, in order for me to be able to help You out any further, just let me know what I'm dealing with...
...or...
...I'll be going on another...
..."Wild Goose Chase!!!"...lol.
Be Safe, take care, and have a good one.
RockysRoadshow
Thank you for your quick response, you seem like real car guy. I appreciate you knowledge but do not intend to take up your time with a wild goose chase. I intend on working at getting this carb working this summer and figured there might be something obvious that I overloooked the first time.
The car is a 1978 Dodge Aspen Super Coupe, a relatively rare car (531 produced). Originally with a 360ci police interceptor engine but rebuilt into a 408 stroker, larger cam stroker kit, ect. The rebuild has taken the engine from 200hp to about 390hp and 480ft lbs of torque. I am having trouble with the THERMOQUAD CARB (rebuilt). I do not have access to my specific carb at the moment however I know that it is approx. rated at 800 cfm.
It's been nearly a year since I've had the thermoquad installed. I remember that this loss off power happened at about 4000-5000 rpm and mainly at WOT. At the lower rpms under WOT there is no hesitation and performs dramatically better than the eddlebrock, which I unfortunately can't get the model number of either at this moment.
The car has had exhaust modifications, we have added hooker competition headers which go through 3.5 inch diameter side pipes.
The air filter has been replaced, same with the fuel filters, have even tried a run with out some of the fuel filters. We have replaced the mechanical fuel pump for a higher pressure electric pump.
Both larger and smaller jets have been tried to fix the issue, maybe a small (positive effect) from the largest jets but didn't solve the problem.
The car is ran on about 94 octane gas.
Ignition is from a mopar performance orange box and a mopar performance distributor. Spark plugs are quite new and should be in good condition.
Thank you very much for your time but don't be too concerned with my carb problems, it's a project car and I have no problem working on it until it's fixed.
SteFFy7469
Greetings SteFFy7469....You are welcome, for that other Quick (Reply) Response, and, Thanks for providing me with most of your Car/Engine information, as, the more that I know about your "Ride", the more that I will be able to help You out, my Friend...and...please don't worry about taking up any of my time, because, "Cars, Trucks, and what makes Em Go" is a very "Major" Hobby of mine!....Let me start with some "Basics"....An Engine like Yours, "Needs"...Proper Ignition Timing...Proper Carburetor Air/Fuel Ratio, for all Engine Operating Conditions, at a "Flow Rate" that will support the demands of your "Modified" Engine, while at WOT and High RPM's...and...an Exhaust System that is able to "Flow" the amount of Exhaust Gas that comes out of Your Engine's "Heads" Exhaust Ports, without any "Exhaust Flow Restriction" especially at High RPM's while at Wide Open Throttle (aka, WOT).
Now, let's do some "Eliminating", shall we...
By what You said about Your Cars "Exhaust System", I can't see any problem with the "Exhaust Flow Rate" at Higher RPM's, but, You may have noticed, because of having virtually "No Exhaust Back-Pressure" with Your Exhaust System, that, Lower RPM's are a little weaker then, that, of what You may have had, with the "Cast Iron" Exhaust Manifolds installed on Your Engine.
I thought that I would mention about the Weaker Lower RPM's Torque/Horsepower, just in case an issue or two arises, about Your Engines "Personality" while it is Running in the Lower RPM's Operating Range.
Also, if the Camshaft that You have in Your "408-Stroker-V-8" is Reasonably "Aggressive" (and is usually accompanied by a "Lumpy Idle" as well), that You may have noticed that, You have to get the RPM's up a bit, before You really get going at all.
I'll save many more Considerations that I have, for a later date.
Now then, I'll state a few things on "Ignition Timing", and, save the "Carburetor Stuff" for last.
In Your case of having problematic "Engine Operation" at about the "4000 to 5000" RPM Range, Your Distributor's "TOTAL" Timing has to be "Correct" for both Your "Engine", and The Fuel that You are putting in Your Gas Tank (I say that, just in case you put a different, or Lower "Octane" Gasoline in Your Gas Tank, which usually will require a Lower "Total Ignition Timing", to avoid Knocking and Pinging that could very well "Harm" Your Engine!).
Your "TOTAL" Timing, in "Degrees" as measured at Your Engines Crankshaft, has to be, as they say, "ALL IN" Before Your Engine's RPM's reach Your Engines problematic "4000 to 5000" RPM's. (a "Ballpark Figure" would be around 34 Crankshaft Degrees (maybe a few Degrees "Less", and some People have found a few Degrees "More", works for them) Before Top Dead Center, but like I say, this is just a "Ballpark Figure!!!"), and, be "Very Careful" when having Your Engines "TOTAL" Ignition Timing Set, or Your Engine can be "Damaged, or even Destroyed", if You happen to "Over-Advance" Your Engine's "TOTAL" Ignition Timing!
A Ball Park, "ALL IN" Ignition Timing of approx. "34" Degrees (Verify what "Your" Engine "Actually" Requires, for "ANY" of Its "Ignition Timing Needs!!!), might be, "ALL IN" by about "3000" RPM, and Your Engine might need a "Different" All In, as well as any "Other" Ignition Amount or Specification.
"Total Timing" = is when you "ADD" the "Initial Timing", that is usually measured with a Timing Light, on the Crankshaft Damper/Timing Tab, while the Engine is at Idle Speed, to the 2 Advance Weights Maximum Timing Advance, when they hit their Stops.
Before I go any further, there can be some "Confusing" matters that pertain to the following...
...make sure that You, or Anyone, are Fully Aware, that, there are "2-DIFFERENT" Degree Specifications!!!...
"Crankshaft degrees, are just that, Degrees that are measured at the Crankshaft, or in other words...What You See, is, What You Get!...lol...
...where-as...
...when it come to "Distributor Degrees", then a Person "Has to Always Remember" that the Distributor "ONLY" Rotates at 1/2 (one half) the RPM's that the Crankshaft Rotates at!!!
So, just pay very close attention to, if it happens to be "Distributor Degrees" or "Crankshaft Degrees", or, your Timing is going to be..."ALL MESSED UP!!!"
Let's see what a Hypothetical "Total Advance" could be, with the following scenario, shall we...
The Distributors Centrifugal Advance Weights have been set up for "24" Crankshaft Degrees (Not Distributor Degrees!), and, we set the "Initial" Timing at Idle speed, to "10" (Crankshaft) Degrees Before Top Dead Center.
By Adding the "Initial" Timing to the Advance Timing of "24" (Crankshaft) Degrees, as provided by the Advance weights, we arrive at a "Total Advance" of "34" Degrees (at the Crankshaft)...and...with this "Total Advance", this is the Amount of Crankshaft Degrees that should be "ALL IN" at that "3000" Engine RPM, or whatever "Your" Engine "Likes", for an "ALL IN" RPM Specification.
Please Note..."Do Not" Include the "Vacuum Advance" in Your "Total Timing", as, when You "Put-The-Pedal-To-The-Metal" (aka, "WOT"), the Intake Manifold Vacuum Level drops to almost "Zero!" (or, close to nothing at all).
Check to see what Other People, and especially if they had their Engine on a "Dyno" (aka, Dynamometer), that have an "Engine like Yours", and are using a Gasoline "Octane Rating" comparable to Your "94" Octane, or "Lower Octane", if you have to go that route, due to the Pump Gas that is available in your Area. (unless, You happen to be adding some "Octane Booster" Concentrate to Your Cars Gas Tank, that is).
As You can see, there are "So Many Variables" that can have an "Effect" on the way in which "Any" Gasoline Engine will "Run & Perform!"
Now then, Lettuce (aka, Let Us...lol) move on to some of that Good Ole Thermoquad Carburetor Stuff, shall we?
At this point in time, I'll just address a typical Thermoquad Carb, as well as, what Your particular "Model and Year" of Thermoquad, may be adding, in the way in which Your Engine is running, at that problematic "4000 to 5000" RPM Operating Range.
Got your "Snack and Drink" yet...
..ok, I'll assume that..."All Systems are Go!"...lol.
Seeing as how Your Thermoquad may very well be a "1978" Year/Model, I'm thinking that You have either an "800 CFM, or an "850" CFM (CFM = Cubic Feet per Minute Flow Rating).
The "800" CFM Thermoquad usually has 1 3/8" (one and three eights of an inch) "Primary Throttle Plates" (aka, butterflies), and the "850" CFM Thermoquads usually have 1 1/2" (one and one half inch) Primary Throttle Plates.
Even if You happen to have the "800" CFM Model of Thermoquad Carb, that should be, a "Large enough Flow Rate" for Your "408" while at "Redline", and at WOT, as well, as I see it.
The added advantage with having the "Smaller Primaries" that are in the "800" CFM Thermoquad, is that, You will probably have a very "Crispy" (super responsive throttle, especially while driving around at City Speeds).
Warning...If indeed Your Thermoquad Carb is a "1978" Model, I'm thinking that, it may very well be, "Calibrated" on the "Lean" side! (Lean = Less Fuel, in the Air/Fuel Ratio), and, that alone, will cause a High Performance Engine like Yours, to be "Acting Up".
Hopefully, Your Thermoquad Carb, is Not a "Lean Burn" Model of Carburetor, because of the "Things", that they did to it, back then, not to mention the "Electronics" hidden in the "Thing-ah-mah-jig" that was mounted on the air cleaner housing.
There are a few things, that I can think of, off hand, that You might want to do, or try, on Your Thermoquad Carb, and, if it actually "Is" Your Thermoquad causing that Running Problem at the 4000 to 5000 RPM Range, then, here Ya go...
Firstly, Your "Choke Pull-off" has to be in "Like New" Condition, or, it "Won't Let the Secondary Air Valve Open Properly!"...and, the Secondary Air Valve will act "Just Like a Choke", and that will provide Your "408" with a..."Way Too Rich" Air/Fuel Ratio!"
My advice...Install a "Brand New" Choke Pull-Off, or, You will be fighting a Losing Battle!...and...make sure, that You "Adjust" that New Choke Pull-Off, as per Specifications (there are some Custom Adjustments that can be made also).
Now for Your Thermoquads Secondary Air Valve "Torsional" Spring (usually incorrectly called a Tension spring) "Adjustment!"
Try Adjusting Your Secondary Air Valve Spring "Wind Up" (Wind Up = the Amount that You Adjust for, on Your Thermoquads Torsional or Tension spring that controls Your Secondary Air Door).
I have a number of Videos (actually, Many!, or Lots!) of Stuff on the Thermoquad Carburetor, and one that Specifically Describes...How to "Adjust" the Secondary Air Valves "Torsional" Spring.
Just type...RockysRoadshow...in the Search Box, at the Top of UA-cams Main Page...as that should show You a Listing of the 80 UA-cam Videos that I have made to date...Most of them are Automotive related...enjoy.
Now, back to that Secondary Air Door "Spring" Adjustment....Just loosen off the screw threaded "Lock Ring" (it has 2 slots in it, and it surrounds the Adjustment "Screw"), then, loosen off the "Adjustment" Screw Slowly, until the Secondary Air Door Flops Open...Then, "Slowly", turn the Secondary Adjustment Screw in the "Tightening" Direction, until the Secondary Door starts coming back up, until it "Just Touches" the Air Horn Boss (aka, top aluminum casting), then, Slowly, turn it an "Additional" 1 1/2 Turns (one and one half turns) from when the Secondary Air Door just "Touched" that Upper Aluminum Casting Boss (Boss, is just a fancy word, for a protrusion)...and..."Don't" Forget to Tighten the "Threaded Locking Ring!!!"
Please note...Make Sure that the Inner Screw "DOES NOT" Move or Spin, when You Tighten down the Locking Ring!
(That so called Adjustment Screw, Isn't a Screw at all!...as...It Doesn't have any screw threads on it!).
That 1 1/2 Turns Secondary "Torsional Spring Wind-Up" Amount, that I had just mentioned, is a very "Good" Starting Point to start at.
I would also recommend..."NOT to go Past 2 or 3 Turns" on the Secondary Torsional Spring, as it happens to be telling me, that something "Just-Isn't-Right!", well, in as far as the Secondary Jetting, that is.
I had a best result, setting me Secondary "Torsional Spring" Wind-Up....Set for 1 1/4 Turns, as, that's, what worked Best for me, at the time, and, I actually "Removed" the Choke Pull-Off Diaphragm, as I found out, that...I "DID NOT" Need it, due to having a 4-Speed Manual Transmission (You know, that there 3rd Pedal, just to the left of, that there brake pedal, also known as the...Clutch Pedal!...lol).
Also, while I remember, my "850" CFM Thermoquad was on a 360 Cubic Inch V-8 (Factory High Performance Version), and it came from the Factory with .143" (one hundred and forty-three thousandths of an inch) "Secondary Jets" (aka BIG Ones!).
See what "Secondary Jets" that are "Hiding" inside Your Thermoquad, and "Record" (aka, write it down), as I have seen some "Small" sized ones in the past.
You might have to go to something like I had, You know, about .143" Secondary Jets, especially seeing as how you now have a "Gas Guzzler!...lol
"ALL" Linkages and Adjustments on each, and every Thermoquad, have to be "Correct", and done in the Proper "Sequence", or, there'll be "Trouble-in-Paradise!"
Thermoquads, like any of other of the Carburetors out there, will benefit from a "Fresh & Proper Rebuild".
I just noticed that You Added a "HIGH PRESSURE" Fuel Pump!!!
That my Friend, is a..."BIG NO-NO", when trying to supply a Thermoquad Carb with "TOO MUCH" Fuel Pressure!!!
To me, a "HIGH VOLUME" Fuel Pump, might be OK...but...
...A "HIGH PRESSURE" Fuel Pump, that supplies any more then about "7" PSI (Pounds per square inch) to the Float System, will more then likely "OVER-POWER" the Floats "Ability", to "Apply" enough Force to the "Needles", that Need to be making Positive Contact to the "Seats" Orifice, or hole, if you will!...
...or, in simple terms...Any More, then about "7" PSI, will probably be "Forcing" Gasoline "Past" the Needles and Seats, as the "Floats" "ARE NOT" able to Apply enough Force to the "Needles", in order to "Seal-Off", that there "Very High Pressure Gasoline!!!"
Just remember, no more then about "7" PSI Fuel Pressure, No-Matter How Fast (RPM's), or under what given load that the Engine may be subjected to!
Also, Your Fuel Pump (be it Electric or mechanical) "Must" be able to supply Enough "Volume" (Not Pressure, as that is limited to about, no more then "7" PSI, or perhaps, just a little less).
Make sure that Your Fuel Pump is able to keep Your Thermoquad's Float Bowls Filled-Up, especially at "WOT", where there will be...a "Very High Fuel Consumption Rate!" (Ball Park Fuel Pressure should be around 5 to 7 Pounds per square inch, and, if it falls way Too Low, You will probably be having a way Too Low "Wet Fuel Level" in both of Your Thermoquads Float Bowls!).
I'm thinkin...Try and find the "Fuel Pressure" Specification for, perhaps a 440 Cubic Inch Engine, as the 440 will probably have similar "Fuel Pressure" Demands (and maybe Fuel Volume as well perhaps?), that will probably, at least, give You something to go by.
Here's something else to consider, as to Your Thermoquads Calibration/Jetting...
Gasoline, back in 1978 was a very "Different" Gasoline, as compared to the Gasoline that You put in Your Gas Tank These Days.
I find that Today's Gasoline, Did make my Thermoquad Run quite a bit "Leaner" then when it was "Calibrated" for, as in, the good ole gas of the 70's.
Warning...about those 2 (Black Plastic) "Nitrophyl" Floats, that I happen to think, that may be "Hiding" inside Your Thermoquad, are Known, to "Absorb" Gasoline", and over time, just might "Start to Sink", which will almost always cause an "Overly Rich" Air/Fuel Ratio, and, I actually "Saw", One of my Thermoquads "Primary Nozzles" (in the Primary throttle bores) actually "Dripping" Gasoline (as in..drip, drip, and even more drops of Gasoline), and that was when the Engine was Only at "Idle Speed!"
In closing, and shall we say...Time to wrap it up...
...It's Very Important to Verify Your Engines "Total" Ignition Timing, as Ignition Timing can "Make or Break" Your Engine! (Literally!).
Don't forget, there is actually "More" to Ignition Timing then You think, as in, everything, including..."Initial" Timing (aka, usually the amount of degrees Before Top Dead Center, as measured at the Crankshaft Harmonic Balancer, or Damper, if you will, and its position relative to having an "Accurate" Timing "Tab", that has been "Verified" on Your Engine), "Amount of Advance", and how quick it comes in, as well as the point, in RPM's where it just Starts to come in....also, "Vaccum Advance", that is usually a "Givin", on a Street Driven Vehicle, and used mostly for "Economy, and getting way better Gas Mileage/Kilometer-age" as well, when the Vehicle in question, is just "Cruising" along, and with having a very light Gas Pedal Applied as well.
Seeing as how You probably have many $$$ Invested in Your "Limited Addition 1978 Dodge Aspen Super Coupe", and Your 408 Engine", I would Strongly "Recommend", that you go out and purchase an "Air/Fuel" Ratio Gauge Kit, that comes with a "Wide Band Oxygen Sensor", that will be able to "Display" Your Engine's Air/Fuel Ratio, while You Drive at different Speeds and Throttle (aka, Gas Pedal) Applications, that way, You'll "Know and See", just what Air/Fuel Ratio, that Your Thermoquad Carb is Feeding Your 408 Engine, while Your Engine is just "Idling", and, also, at all the Engine RPM's, while being under "Very Light Loads" while just Cruising along, up to, and including, a rather Heavy Load at "WOT" from a Standing Start!
"Too Much" Ignition Advance is "Harmful" to almost any Engine!...
...and, If You happen to be Hearing any "Knocking" or "Pinging", that is a Sign to me, that, the Engine in question, is at "Risk", of having some "Very Expensive" and "Destructive" Engine Damage happening, as those "Sounds or Noises" are in effect!
Same thing can be said about Running an Engine with a "Too Lean" Air/Fuel Ratio, as Running an Engine on a Too Lean Air/Fuel Ratio can and will, eventually Cause some very "Major" Engine Damage, that has been know to..."Drain the Bank Account", but only "If", You intend to "Repair" all of that Engine "Damage", that could have been "Avoided in the first place, so then, "Listen Carefully", that's if You can Hear anything Other then...
...Your (Maybe?)..."Loud" (Exhaust) "Side Pipes!!!"...
...I hope that some of the above, is able to help You out, to some degree...
...till next time...
...Be Safe, take care, and have a good one.
SteFFy7469
Greetings SteFFy7469....I did receive your Personal Message in my Inbox, and, Thank You, for your kind words....What I normally like to do, is to keep all Postings related to any of my UA-cam Videos, out in the open, so that the Public at Large may benefit from the dialog that is being discussed at any given time....I do however respect your need to keep it in a private domain, if that's what you desire....Now then, "On with the Show!"...lol....I watched your "408" Engine UA-cam Video, and, it sure sounded "Awesome!!!"....Congrats on Your D.I.Y. (Do It Yourself) 408 Engine installation in Your "Ride!"....Well done!
Good to hear that Your Fuel Pressure is about right for Your Thermoquad Carb!
Just remember to "Change Your Motor Oil" in Your 408 Engine reasonably soon, as there will probably be "Lots of Metal Bits and such" findings its way into Your Oil Pan, due to Your 408 Engine "Breaking itself in".
Just think of the "Crosshatch" Pattern (Honing Finish in all 8 cylinder bores) in Your 408's Engine Block, and the Pistons Rings "Seating" themselves in, and scraping against those 8 Crosshatched Honed cylinder bores!
Yes-Sir-ee-Bob, there is inevitably going to be all kinds of metal bits, and then some, and there is no stopping that, when a "New" or "Rebuilt" Engine gets started and running for the first time!
From what I recall, just about every "New or Rebuilt" mechanical part, such as Rear Axle Ring and Pinion Gears, Engines, Transmissions, Bearings, etc., need to be "Broken-In" for about at least 500 Miles.
So before You start "Racing Your Ride", Take it Easy for the First 500 Miles or so, in order to let any, and all "New or Rebuilt Parts", Wear In, Seat, or even call it, Parts Conditioning if you like, because, once those New or Rebuilt Parts are "Broken In Properly", each of those Parts "Will" be Lasting Much, Much Longer!...But Racing, well, that's a whole "Different Story!"...lol.
I suggest that You Start and Run Your Engine at least Once-ah-Month, and the More, the Better!
Why You ask?...
Here's why...I had a Flat Tappet/Hydraulic Lifter Camshaft's Exhaust Lobe "Disintegrate" on a Chevy 350 Cubic Inch V-8.
Also, had a 2-Piece Rear Crankshaft Seal, on a different V-8, Dry-Out and start "Leaking"...
...and, if you leave an Engine sitting "Dormant" for a very long time, there are Engines that get "Seized-Up" due to the Pistons and Piston Rings Corroding/Bonding to the Engine Blocks Cylinder Bores!...
...I figure that, the Above "Ugly-ness", was due to "Not Starting and Running the Engine Often Enough, and getting that Motor Oil Circulating, to Lubricate the Engines Internal Parts!!!"
So then, especially if Your Engine has Flat Lifters, either Mechanical or Hydraulic Type, then, I "Strongly" Suggest that You Start and Run Your Engine Up-To Operating Temperature, No-Less the "Once-ah-Month", to avoid some, Down-Right Expensive and Not Appreciated Engine "Damage!!!"
I'll add this here...If Your 408 Engine Does Have a Flat Tappet/Lifter Camshaft in it, perhaps, try to find some Motor Oil with some "Zink" in it (I think that's what some experienced Guys were speaking of, a while back) in order to ensure that Your Camshaft and Tappets/Lifters, get the Proper Lubrication and Protection, as, most of the "Newer" Motor Oil Manufacturers/Producers have taken out, most, if not all of the "Zink" that use to be in the Older Motor Oils, way back when.
If in fact, You Do have a Roller Camshaft, and Roller Lifters in Your 408, then, it will be way more forgiving, in as far as the Camshaft Lobe "Destruction" scenario is concerned.
Always Remember, that, "ENGINE EXHAUST FUMES ARE DEADLY!!!"...so, MAKE SURE, that You Have LOTS OF FRESH AIR AND VENTILATION, as in, KEEP THE BIG GARAGE DOOR FULLY OPEN whenever Your ENGINE IS RUNNING!!!
Here is one More "Disaster" that You can also avoid, as it relates to a Vehicle's Parking/Emergency Brake, while the Vehicle in Extended Storage.
Here's what happened to me...
...I had a Car, parked in my garage for a few years, and, when it came time to move it out-ah-there, my Rear Brakes (Drum Brakes) were "Locked Up Solid!!!"
Hmmmmm, why is that, I was thinkin...
...I came to the conclusion that, the Rear Brake Shoes actually "Bonded" to the Brake Drums!!!"
Damn Car was parked up tight on one side, very close to the garage side wall, so, I had to put a hydraulic jack under the rear axle, and drag the car sideways, so I could get at the wheel and brake drum that was so very close to that garages side wall...
...Man, not something that I ever want to do on a regular basis, that's for damn sure!
So then, if You have Drum Brakes on Your Car, You can avoid the "Brake Shoes Bonding to the Brake Drums" Scenario, by just leaving the Emergency/Parking Brake "Off", but be Warned, Your Vehicle should be on Level Ground, Transmission in Park or 1st gear if it's a Standard Transmission, and all 4 Tires must have Tire Chalks (aka, Bricks, Lumber, etc.), to keep the Vehicle from Rolling away, and possibly Injuring Someone, or, crashing into something as well!!!
That's all for the time being...
...Be Safe, take care, and have a good one.
I've got one that was sitting inside my 70 charger when it was retrieved. but its froze up solid. looks like it had been sitting in water. I'll do a video on it tomorrow and put it on my page.
+Aziz Lamar Greetings Aziz Lamar....Thanks for watching........................Here's what I would do, if it were me, having the Carb, that You were just talkin' about...............I would Carefully, Remove all of the Screws, and, Carefully, Take "it" Apart.......................Then, Clean it all up.........................Then, by taking a close look at "it", that, in itself, would probably be tellin' me, whether, it was, or was not, "Rebuildable", to the point of, having this particular Carb "Working Properly", and as it should be doing...................In the event, that this particular Carb, was "Too Far Gone", then, a good place to start looking for, the "Exact Same Carb", would be on...E-Bay..................................Some, might be almost New Looking, or Rebuilt (properly, I hope), and, the Price of them, is usually, not all that bad, as well, most of the time....................................Make sure that, You Record/Write Down, the, usually..."4 Numbers, with the Letter S at the end", of those 4 Numbers, that You should be able to see..."Stamped Into"...the..."Lowest, Left Rear Corner"...(as Viewed, from the Back), of Your Thermoquad Carburetor............................Use those..."4 Numbers, with the Letter S at the end"...when-ever You happen to be Ordering any "Parts" for that "Exact Thermoquad" Carb, to be sure, that, You get the Correct Parts for it....................Well......till next time.............Be Safe, take care, and have a good one.
RockysRoadshow thanks. I'm about to shoot a video of it and upload it onto my page. Its should be there in the next 15 to 20 minutes so you can get a glimpse of the problem. Thanks again for the advice.
RockysRoadshow all right sir I've put the video on my page by the title of "The thermoquad. Rebuild?'' on my page. You can redirect to your UA-cam page click the blue person by my name and it should lead you straight to it so you can give me your opinion on can it be rebuilt or not. Thanks.
+Aziz Lamar Greetings Aziz Lamar...I watched Your Thermoquad, UA-cam Video, and, it sure looks like it has seen better days alright............................All of that corrosion-like stuff on the Thermoquad's Aluminum, top and bottom Castings, as well as the rust, that is seen, on the Steel parts, at times, can be caused, by being Stored, in a some-what, Cold, and High Humidity (lots of moisture in the air)...environment, for quite a long time...................I saw that, someone, in the past, Bent some of those rod-like Linkages, in about, the middle of them......................Perhaps, put some Penetrating Oil, on all of the Screw's...screw-threads, to dissolve, some of that corrosion-like stuff, that usually takes place, when-ever Steel (the Screws), are in contact, with the Thermoquad's, Aluminum Castings, so, the Steel Screws, Don't Rip-out, the Aluminum Screw-threads, while trying to remove them, oh and..."Don't Forget about the 2 HIDDEN Screws"...that are Hiding Under the Choke Plate...!!!.................................Also, put some of that Penetrating Oil, on all of the "Moving Parts" as well, in order to have them Move Freely, once again...hopefully................................If and when-ever, You get Your Thermoquad apart, You will be able to actually see, just how good, or bad, the Inside of it looks, that's for sure......................................Even "If"...???...You actually do, rebuild Your Thermoquad carb, there's going to be some Money needed, for some "New Parts", and are as follows......................I Usually Purchase and Install........the Exact Rebuild Kit.......2 New Floats (the Brass ones)......and.....a New Choke Pull-Off (that be that little space ship lookin' thing...lol), so the Thermoquad will work properly, once all of the Adjustments/Set-up, are done, in the Exact, Specified Sequence/Order, according to the Rebuild Kit Instructions, and/or, a Factory Service Manual, if one is available, that is.................................You are looking at, about $100 Canadian Dollars (retail) or more, just for the few parts that I just mentioned..............................Once You find out, what those..."4 Numbers, followed by the Letter S"...are, do an Internet Search for...Vaanths Thermoquad Guide...or just...Vaanths Guide...and, once You find it, there is LOTS of Information, about so Many of the Thermoquad carburetors, that were built over the years...................You can Look-up, just about any Thermoquad, using those..."4 Numbers, with the S at the end"...and, most of the Specifications, will probably include, things, like, Primary and Secondary Fuel/Jet Sizes, as well as, the Step/Sizes, for the Metering Rods as well.........................Check Your Thermoquad's, Primary Throttle Bores/front ones, to see if, they are...1 and 3/8 inch Diameter (800 CFM/Cubic Feet per minute, Air/Fuel, Flow Rating) or, 1 and 1/2 Inch Diameter (850 CFM)..........Vaanths Thermoquad Guide, will probably show You, just What, Year and Engine Size, that those 4 Numbers, followed by, the letter S", that's found on, just about any Thermoquad, was Originally Installed On, right from the Factory, when brand new......................So, if and when, You might, Open Up Your Thermoquad, perhaps, make a UA-cam Video of it, so I'll be able to see, what's happenin', inside of it as well...thanks.......Till next time..............Be Safe, take care, and have a good one.
RockysRoadshow OK thanks for this good advice on the thermoquad. You've been very very helpful. Moneys a little dry right now. It might be some months or so but when I do tear open the thermoquad I will do another video and mention you again and show the thermoquads insides. Thanks again for your help,advice,and thermoquad videos. I'll hit your subscribe button. Thanks again