How to adjust timing - 350 Chevy small-block | Hagerty DIY
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- Опубліковано 23 жов 2017
- In this Hagerty DIY, Kyle Smith walks you through the process of adjusting timing on a Chevy small-block engine.
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Been a diesel mechanic for 2 decades but haven't worked on a small block in 10yrs, great refresher! Thanks for keeping it simple, even a newbie could follow along. Love the simplicity of older Chevs, nothing better!
just fixed my truck thanx to you.. thank you so much you have no idea the stress and trouble you saved me
Nice! Great to see some "old school" vids. Something to mention is that carburetor settings might need adjustment once you get the timing set.
It’s so beautiful the way it just started at the end... man...
I’m a rookie mechanic (max green around the ears) and this is my first time doing this. Thanks to this video and excellent narrative I managed to set the timing with very little difficulty. Thank you for the outstanding instruction video.
A little older (OK A LOT probably:)) but take advantage of these DIYer videos, when I learned (as a Greenie) it was reading oil stained books with missing pages:) and Ole School Shade Trees that were as quick with a lesson as they were with disparaging remarks:):) Man, these videos are so instructive they'll make you believe you can rebuild a trans on the side of the road:):)
Nice Founders sticker on the tool box, they are one of my favorite breweries too.
I've been working on engines for 50 plus years and finally at age 77 I understand what I've been doing wrong when I timed an engine. Wondered where the ping came from and why acceleration felt like I was dragging an anchor. Great presentation thanks
Thanks for the video, definitely forgot to plug the vacuum advance when trying to time my truck lol!
Don't take the timing light off until you tighten the distributor hold down bolt. Often times it moves a bit so check it again after it's tightened to ensure it's still where you want it before you unhook it and put it away. Sometimes you have to loosen it and set it again... its easier to have 2 people when you do it. One to run the light and one to turn and tighten.
Could not have found a more useful video, I have a 73 C10 with the 350 so it’s pretty much the same process for my truck, thanks
im new to this and had a basic understanding. but have no clue how to fine tune any of it. this was very helpful in starting back from square one
You missed setting points & CONDENSERS. 😁
Match book worked good but they bite like Zeus if you did it wrong. Whiplash yer arm off your body
Kyle! Thanks for the journey back to when I was about your age, adjusting the timing on the 3.8L V6 on my collegemobile, a 1981 Buick Century.
A poster on another forum is having trouble with the timing on their Century, same year. He claims he followed all the steps, including disconnecting some electronic thingy.
He didn't mention whether he just did ehat I did: disconnect and plug the vacuum advance hose, then perform the timing adjustment.
I have a comment I didn't unplug my advance timing after setting everything do I just unplug it and then check my timing again thank you I really enjoyed your video it showed things that other videos don't show God bless you all and have a blessed day
Thank you for creating and posting this.
On my old pontiacs, I just give it as much time as I can an still start the engine! Works good!
I just bought me a 1981 chevy c10. I've always owned newer cars and trucks and this being older then me is a trip on how simple it is but at the same time its a whole new world. I still need to fix the timing on my truck right after I figure out the whole vacuum lines going to the carb (previous owner took everything apart that has to deal with the carb) Good thing is I got it started but it sounds like its about to die.
A pencil stub is an excellent vacuum plug.
Safety tip, always connect the ground /negative last. If it's grounded when the hot side is connected it could spark.
Use a glittery pearlized nail polish to mark your timing marks as it's much easier to see.
i painted cranshaft pully black then use a tooth pick and white paint to mark degree tiny grooves (out standing ) with flashing light
@@frankdavidson9675 that certainly works too.
Definitely going to help me next weekend when I go to time my truck
Hey my friend I've been a mechanic 36 years and I still struggle with things especially on my own machines I'll tell you what you're one hell of a guy you help me out a great deal definitely a good explainer right to the T!! Therefore and they're being I have no questions I understood every word you said thank you very much and keep them wrenches turning 💪🏼💪🏼💪🏼😉
Got a 69 gmc - they are great trucks!
Nice video. Very clear. Great Job.
Road time it. Advance little bit at a time until pinging starts on a hard 1st to third or 2nd to fourth shift...then back it off a bit. This is how I timed cars back in the day after getting it close with a light. Nicely done video!
Every other time I drive my350 I get pings and when I goose the gas I’ll get backfiring. Wich way should I rotate my distributor?
Clockwise
It's like being in Auto Shop again in High School....lol...Thanks.
Also that knob on the back of timing light is to check total advance. You bring rpm up then while holding it there you turn the knov until the timing shows back at zero and you read the knob which tells you the total advance.
That is correct. Total timing is way more important than initial timing. The advance springs in most distributors are super strong and don't allow full advance until 4k rpm or redline. Not what you want. I take the springs out so you don't need very high rpm to achieve total timing while you're under the hood...I like my hearing lol
@@paulkessler8622 What RPM should total timing be at?
@@ghatazhak4265 it's whatever rpm will allow the weights to fully extend out, depending on the springs you use. I usually remove the springs, then only rev it to about 2k rpm, set it, replace springs, and done.
@@ghatazhak4265 I like my total timing all in at about 3000rpm. 32-34 degrees on the sbc.
@@paulkessler8622 sometimes it’s a balancing act. As parts wear things get off from the base factory numbers. “ stacked tolerances” will have an effect. So, when one sets timing to say full advance, the initial timing can be off enough to cause hard starting etc.
The opposite is also true, setting initial time in general dead on and full advance might be off quite a bit.
Personally I set the base, and check the advance, and , if need be, tweak either/or until a happy compromise is met.
Easy starting and acceptable road performance. Now this is for a daily driver of course. A race or high performance application one wants max output.
You should always double check your timing after you tighten your distributor just to make sure you didn't bump it accidentally it does happen sometimes so why you have the light still hooked up it doesn't hurt to check it and then take it off
Robert Waldrop usually it’s due to the hold down grabbing and turning while tightening it down.
Also, turning the distributor via the cap? Not the only one who cringed at that am I?
I couldn't agree more. I've had to fight this exact problem.
@@dylnbxtr o6i⁷67⁶
It's a great job thanks for the video
actually bought a 1969 chevy c20 today. transfer of ownership takes place at the dmv tomorrow in the morning and im here because the motor needs to be overhauled as it burns oil do to bad piston rings. that being said, I want to install a 465 lift cam with a 224 duration to increase performance of the engine. so im here to learn timing
how did you deside its the rings could be the valves ???????? this is a tip for new guys burning oil take plugs take compression readings now add small spoon of mtr. oil each plug hole re take comp. readings did it help then its the rings if it does not help its the valves they need grinding
Im setting here thinking a long time ago..wasnt it 4before4 on those old small block..to set the timing..i always used a white marker and marked that balancer..just thinking back..really nice truck.. i had one once.
Man, the last car I timed was my new '87 Mustang GT. IIRC, I installed a cooler 160 degree thermostat and removed the air box silencer to free up the airflow a bit. I think I bumped it up 2 degrees and only used premium fuel from there on after. I used to do the fun meal deal on my older cars quite often. I bet I changed the plugs, wires, rotor, cap, condenser every year. Now cars can go 100,000 miles between tuneups. Back in the old days I used to think 100k was end of life for engines. heh
Awesome video 👍
I gave up on partially rebuilt bases, and bought a new billet one a few years back. I can't remember now exactly what I dialed in, but I got ported vs. manifold sorted out, and set the advance curve up to something that the 305 loves.
What advance curve did you use and what did you decide on ported vs manifold?
@@paulkessler8622 you never seem to get a reply from people?
@@peacepoet1947 A lot of times lol
Nice and easy not like todays cars where you have to be an automotive surgeon and have $5,000 worth of tools just to change a light bulb
Vanmyster94 haha yep that’s why I have a 1983 Chevy 350 k5 blazer
You laugh but I've seen cars you have to take the front wheel off of just to change a headlight.
@@1337penguinman my dad was a mechanic a while back and showed me it was easier to change the back most spark plugs on a s-10 with 4.3 from the wheel wells
I am a collision tech and to be honest its about the same. You have to have knowledge to identify problems in old cars. Carburator adjustment, timing etc also skills you need to make them run right and be correctly tuned. New cars have a ton of modules and sensors, but you plug in your scanner and it points you towards your problem area. Not all of them are created equal though. Some people expect their engine code reader they got off of Ebay to do everything and promptly get dissapointed when they find out the astronomical price tags on scanners that do engine, air bags, abs, body modules, live readings etc.
But I et the point you are making. News cara are like space ships compared to classics. I am a proud owner of a 1971 Chevelle and I also prefer old cars. The less you have moving around when the car is on, there is less to go wrong. Besides they have character and come from a time when hard working Americans expected quality when they spent their hard earned dollars. The new mostly plastic cars will not last anywhere near as long and there are hundreds of thousands of every model. Also not everyone is great with electronics. BMWs are notoriously bad with electronic components, though they have gotten better. They lose their value like crazy in just a handful of years because of that.
Man I'd love one of those old Chevy trucks
They're still out there man. I just bought a 72 custom deluxe on craigslist for less than 2k two weeks ago. It's a diamond in the rough but it'll work for me. Good luck
John Snider I have my eye on a 64 c10, but I'm 16
Ledger Cook I’m 14 and I got a 1981 c10 stepside box Chevy me and my step dad started rebuilding it when I was 12 and we’ve gone through the frame body and the last pice of our puzzle is the carburetor 😃 we will be putting it on tomorrow I’m so excited ❤️ live for these old trucks!!!!
I just picked one up. Needs some work but it was only 1500 bucks and has almost no rust. The only rot is the drivers side rocker.
Dustin Ritchotte cool
Very nice video. Thank you.
nice explained.
Nice thanks for the video
ayyy that's the truck I'm looking this up for lol ✊
Lol no joke me too. I have a 72 C20 with a 350. I laughed when they showed the truck. Perfect!
@@thekehoeshow.. same years later lmao
Vacuum advance does not give more timing so it's 'peppier', it increases the timing at part throttle for smoother running and fuel economy. At part throttle, the engine will create a certain amount of vacuum in the intake manifold. This is because the throttle is mostly closed and the engine is pulling against this restriction. Because the throttle is mostly closed, very little air is moving into the cylinders. So at light cruise, such as running down the highway, the engine is making much less power than it would at this same rpm at WOT. With less air and fuel in each cylinder, the air-fuel mixture is not as densely packed compared to WOT. This less-dense mixture requires more ignition timing to complete the combustion because it takes longer to burn. As soon as you open the throttle, the vacuum drops to zero and the vacuum advance stops working.
Yea but what if you're advance is hooked to the manifold port on the carburetor that has constant vaccum?? It's already pulling on the advanced when it is idling because it's a constant source of vaccum.
I've noticed on my several SBC engines (all 1974 and prior) they seem to like the advance hooked to manifold vaccum. "Peppier" from a dig, smoother on the highways. They also seem to run most efficiently on this side as far as fuel economy goes. On the ported side, they seem gutless and don't have that extra punch I like, also seem to run more carbon carbonous than hooked to manifold.
All GM engines prior to emissions were hooked to the manifold side of the carb from the factory and factory specs calls for it. Now, late 70s and 80s engines, the EGR has vaccum, and the charcoal canisters come in to play as well. It's all got vaccum hoses. The ported side would be used for advance on these because of all that stuff drawing vaccum, and the ported side makes less combustible energy at idle than the manifold side at idle and low rpm. Therefore making it "better for the environment" then they went full electronic, no v/a. You have to pertain the brain of the " dumb " computer these cars are equipped with, or it will not advance and stumble upon take off without a vacuum advance type distributor.
1st generation of hei = Has vaccum advance, electronic ignition with vaccum assist 1978 and prior is a good idea to have a vaccum hei distributor.
2nd generation of hei = no advance, it's fully electronic. For models containing map sensors, tpi, etc. (Computer ignition. If you can hook a diagnostic tool to a port and it's all unmolested, you require a fully electronic hei 9/10 times. You may be able to hook up the old style to these engines but can't use a fully hei version on an older engine.
For low horse power applications, and overall smaller cubic inch engines, especially if all the smog controll and emissions controll bologna & hoopla are still hooked up and functional, I'd definitely hook to the ported side of the carb with my vaccum advance
But for higher horse, higher compression, Larger c.i. Engines, especially older less "fuel efficient" engines, with large cfm carbs, you'd want to most definitely use the manifold side. .especially on generation 1 sbc engines, or older engines equipped with quadrajets, holley from the factory.
I plugged my ported side because I have no AC or accessories or emissions control. , booster and modulator are hooked to the manifold stand behind the carburetor, I also hardline all my vaccum hoses. Never worry about a cracked or melted hose again. Just a very small piece of hose from the flared side of my metal lines, to the ports. About a inch or 2 mostly, booster slightly more hose to allow for the filter. And distance but I'm still hardlined past the valve cover. It also looks cleaner this way, no coiled hoses, droopy hoses, just nice, symmetrical, straight lines bent by my skills to my satisfaction.
By the way: your vaccum advance has an adjustment screw to control how hard or soft it pulls when advanced (how much inches of vaccum it takes to advance all the way/retract) for fine tuning, I always set mine to be the easiest to pull because i like dig racing and want "peak vaccum" & "peak timing" as fast as possible this assures it's running as efficiently and as powerful as possible when stressed to run high in rpms really fast so it'll pull as much air, be able to efficiently burn all the gas dumped with this air, and if its pulling and burning fast, it's putting out more exhaust pressure. There for getting the catalyst in the engine and the waste out as fast as possible. Therefore making more power with a lighter-sucking advance and keeping your engine internally cleaner.
You can also tweak on the modulator valve the same way to fine tune shifting without getting inside the Trans, but this is discussion for a different time lol
Very helpful!
Great video thanks!
Thank you for watching and being a fan!
love the 3 pedals no problem shirt!!!! and thx for the video...
Digging the Military issue Oakley's, have a couple sets myself.
Very good, you should complete instructions about reattached vacuum hose
I RECALL DROPPING THE hold down screw for the points down in the distributor having to take distributor out,some people thought the hold down screw held the whole car together,over tighting it😃.
Thanks
I have done it wrong all this time, adjusting the timing with the vacuum line plugged to the advance canister.
Heck you can leave vacuum open as long as it’s running and 700 rpm or less .
I agree the way you do it is the way I do it.And i'm at least 40 years older than you.....GOOD JOB...
Very well done I learned something that no one has ever told me before I did not know that your suppose to disconnect the vacuum advance prior to timing thank you and you said about 12 degrees before TDC I have a 1978 350 I need to get timed correctly
akbound.prepper dummy
akbound.prepper. I have left the vacuum line connected while setting the timing. In a pinch you can use a vacuum gauge. On a stock engine it should produce 18 to 22 inches of vacumm
good video.
well explained
That's good. Is this the same for a 4.3 tbi v6 ..i want to make sure i don't break any good parts
Are you suppose to reconnect the vacuum advance to check total advance timing?
Love that color on engine bay everything matches great 👍🤘🇺🇸
To loosen the hold-down bolt on the dizzy did you go left or right looked like right and tighten left??? can't seem to get mine to move either way.......
You don't have the 9/16 the 1/2 inch distributor wrench? Something you keep with the points file and points screwdriver, next to the timing light and dwell meter?
if you are having to file your points you have condenser tble --- wrong mfd value or they are defective -----verfy-----
I saw that Dial Back to Zero timing light and was hoping you were going to show us that method. I was wrong. Too bad!
I tend to adjust my engine in Drive if it requires it, and time it at the specified RPM. Other videos suggest that after the timing is set, then recheck your Idle mixture and speed.
excellant
When clamping on the inductive pick up to the #1 wire, the arrow on it is pointing to the spark plug correct?
I’ll throw you a curve on gm engines V8 you can also use cyl 6 because it’s a tdc same time as cyl 1
So I take it that disconnecting the vacuum is equal to disconnecting the spout connection on my 91 f150 302 although that's electronic
Maybe it was my computer but I never saw the mark
I also couldn't couldn't see it...I'm guessing it's the refresh rate of the digital recorder per frame being a different speed to the timing light....it'd probably so much easier if someone could do a computer animation that isn't affected by computer/mobile phone screen refresh rate.m
I also do not have a clue on what the light was doing or where it should be adjusted to???
Hey bud i have a 4 barrel carb Rochester ,that was running with timing a bit advance and the carburetor would bog/ sound like if it would want to turn off but never did. And have to crank it over with gas several time to start it. So I took it to a mechanic he told it was to advanced in the time that's how I know and he properly timed it and it now starts right up. So I was extremely happy. BUT then when I would want to floor it the carb would back fire so I took it back and he said that he thinks I need bigger jets for more gas . What do you think could be causing the backfire? I
Actually the vacuum advance works opposite of what he mentioned..it ads advance at low load and high vacum conditions...so basically when your not under load and light on the throttle it ads advance...
Exactly, I caught that too. He also has it connected wrong on ported vacuum, so it's operating under high load, low vacuum conditions 🤣🤣
He is dumb. I got that too
Where do i get one of those three pedal shirts that you was wearing in video? Thanks
There is also a direction arrow on the pick up clamp. At mine has one
Should of marked the the line on the Harmonic balance wheel. With white paint so you can see it better.
Awesome video thank you for your help. Just curious on your thoughts for a 1970 stock 350 w/rochester 4bbl. Do you prefer ported or manifold vacuum for your distributor advance vacuum source?
Has to be ported
Some distributors have centrifugal weights inside, they dont have any vacuum line.
Sometimes they get rusty & wont spring anymore.
GM engineers found through all of their years of testing that small blocks run best at ~36 degrees before top dead center total timing (~32 if using vortec heads). They also found vacuum advance is most beneficial when connected to full manifold vacuum (meaning the vac port you connect to is pulling vacuum at idle). All vac advance does, is add supplemental timing for low load conditions (idle and cruise) to make the air fuel mixture burn at the proper rate. Lean mixtures (idle and cruise) burn slower than rich mixtures (accelerating or wot) so the fire needs to be lit earlier, which vac advance enables to happen. When connecting vac advance to a ported vac source, you won't have the needed additional timing at idle for that lean mixture (although important, a lot of people dismiss this because how much time do you really spend at idle anyhow?). Also, with ported vac, you'll be adding timing during acceleration to a rich mixture that actually requires LESS timing, not more (which contributes to detonation). Using your vac advance connected to manifold vac, slightly improves mpg, helps with engine cooling, and generally improves engine efficiency.
I've got a S10 with a sbc 350 I believe, I bought it like this and the guy wasn't sure what it came out of so, I've been buying parts for a 74 camaro so I replaced the timing chain and gear at the time didn't know to mark everything or to even line up at 6 and 12 at top dead center well I put it back as it came off took it for a ride and was running rough so then, i found out to line up the marks so I took it apart and lined up the marks as I thought I was supposed to but has very little fire and what fire it does have is yellow spark and now has a whining noise as it turns over and it sounds like it's bubbling out the exhaust. Any ideas, on what I've done?
Don't know if you can help me or not. I have a 1955 chevy 265 v 8, I had the distributor out because of a problem and now that I found that wasn't my problem after all. I lined up the rotor with #1 cylinder and it seems it's still out of time. it will start and run. But it back fires, I've moved the dist. both ways with no luck. I have new plugs, wires and check the gas. lost
Nice factory correct fuel infuser unit
that starter needs shimmed it sounds like but amazing video. im doing a full spark tuneup on my oldsmobile cutlass. this was greatly needed.
I know this is an older video...but I have a problem. I have a stock 350 with a 600cfm holley replacement carb, its running a little rich but ive heard it doesnt effect timing. the engine idled really low and if it wasnt warmed up it would immediatly stall when i put it in gear and tried to move it. i adjusted the time to be right in the valley between the 4 and 8 degree mark (stock harmonic balancer, stock timing change cover, stock adjustment notches, its all stock. n9t even a cam)...and now, it starts up really easy, the starter has no trouble...and acceleration is good, idle is good. but now that ive adjusted it, i get that really strong nostril burning smell. temp is the same, as it was before, right around 210. is it too far advanced? or is it just all of the gunk from running rich burning out? the engine does burn a little oil, ive been running a thicker oil and i also use the lucas additive and a ring sealer additive. its a beater truck i dont mind the burning oil but i also dont want to burn holes in the pistons.
GM engineers found through all of their years of testing that small blocks run best at ~36 degrees before top dead center total timing (~32 if using vortec heads). They also found vacuum advance is most beneficial when connected to full manifold vacuum (meaning the vac port you connect to is pulling vacuum at idle). All vac advance does, is add supplemental timing for low load conditions (idle and cruise) to make the air fuel mixture burn at the proper rate. Lean mixtures (idle and cruise) burn slower than rich mixtures (accelerating or wot) so the fire needs to be lit earlier, which vac advance enables to happen. When connecting vac advance to a ported vac source, you won't have the needed additional timing at idle for that lean mixture (although important, a lot of people dismiss this because how much time do you really spend at idle anyhow?). Also, with ported vac, you'll be adding timing during acceleration to a rich mixture that actually requires LESS timing, not more (which contributes to detonation). Using your vac advance connected to manifold vac, slightly improves mpg, helps with engine cooling, and generally improves engine efficiency.
Nice video good information. But i have a question. Chevy 350 old vortec heads on it. All The process is same?? Thanks
Same exact process, however vortec heads have a more efficient combustion chamber so total timing should be ~32 degrees. Inotial timing should still be around 12-14 degrees
Is it possible to adjust a timing chain from scratch on a 2015 chev malibu? I rotated the sprockets
So I am adjusting my timing how can I tell which way is advance going clock wise or counter clockwise?
can i use that type of timing gun in reverse to figure out what my timing mark should be? meaning if i set the dial on the gun till i find that the marks are on zero the marks on gun would be my timing mark ??/
Well you forgot to mention that the rom needs to be 700 or lower. You also forgot you now need to raise rpm to about 1500. To check your mechanical fly weights make sure it’s not stuck. Then hook vacuum advance up and 1500 rpm to check total advance. Too many time I’ve seen timing set correct only to find out mechanicals were froze open and would not give a good total advance . Also if its points style set your dwell first. Every two degrees of dwell changes timing 1 degree....
i dont disagree with your comment but i am somewhat confused how dwell is in this picture the points open it fires the dwell is how long they stay open by the time they are full open its already fired ----- set the record straight for me
all the points do is lift the gd off the condenser and coil conn as they open there is no current flow thru the points unless it has wrong condenser mfd value or the condenser is defective in that case the curren has to jump the open gap to gd.causing points to pit over time
@@frankdavidson9675 dwell is how long they are closed.
Nice
Ukroboy pro Gaming 93
Gmc. Jimmy. 4.3. V6
Do you time by vacuum gage, to set at best compression also, what is the negative or positive by this method
The engine is nothing more than a vacuum pump, but using a vac gauge is not the right way to set timing. Back in the day they did it by finding highest vacuum while turning the distributor and setting it there. You can still do that, but you need to follow up with a timing light for it to be exact. Set it to 36 degrees total timing
One of us is messed up and I am taking no bets..... But I have the same setup, same truck model, et al. I went over the booklet with my Edlebrock and I swore the vacuum advance hose was supposed to be coming from the right (DS) tube on the front of the carb. You have it on the left one. Which is correct. I am tuning mine as we speak, so I will switch and see if there is any difference. Then I will dig out the instruction manual again and re-read.
GM engineers found through all of their years of testing that small blocks run best at ~36 degrees before top dead center total timing (~32 if using vortec heads). They also found vacuum advance is most beneficial when connected to full manifold vacuum (meaning the vac port you connect to is pulling vacuum at idle). All vac advance does, is add supplemental timing for low load conditions (idle and cruise) to make the air fuel mixture burn at the proper rate. Lean mixtures (idle and cruise) burn slower than rich mixtures (accelerating or wot) so the fire needs to be lit earlier, which vac advance enables to happen. When connecting vac advance to a ported vac source, you won't have the needed additional timing at idle for that lean mixture (although important, a lot of people dismiss this because how much time do you really spend at idle anyhow?). Also, with ported vac, you'll be adding timing during acceleration to a rich mixture that actually requires LESS timing, not more (which contributes to detonation). Using your vac advance connected to manifold vac, slightly improves mpg, helps with engine cooling, and generally improves engine efficiency.
hi could you tell me what revs the engine was set at to adjust the timming. thanks
at the factory spec for hot idle.
(ie; my '77 k10, with an HEI, a quadrajet, and a manual trans, is 700rpm)
once you re-attach the vacum advance, you will have to re-adjust idle speed, as the engine will speed-up.
Much appreciated. Bout to attempt this. Wish. A. Mf. Luck.
Do you have to re adjust the carbs idle.? I'm having trouble with idle since I replaced my distributor.
I had to adjust my idle screw to get it almost right along with turning the cap. It ran better with idle screw turned more counter clockwise then I adjusted the cap. It silinced some noises too
Hello what model edelbrock carb is that just curious looking to purchase that same one buddy thanks great vid
1406 series
If you can bump the key and it fires up and idles. Timing is good to go
If you cannot easily see the timing mark on the pulley, drag a piece of white chalk over it so the divot fills up with chalk and wipe off the excess from the outside of the pulley. this makes the mark easy to see.
When purchasing an old v8 engine, be sure to get one with the distributor at the front of the engine. this makes this job so much easier. If you own and old ford coupe or bucket that has an engine with the distributor at the rear, you are doing it wrong lol.
To advance the timing, do we rotated the distributor counterclockwise?
Yes
Question when I install harmonic balancer .. i wasn’t pay attention.. went turning so how can I fix 12 and 6 without take off timing cover ?
to get your 12/6 position,,,remove NO1 spark plug and NO3,,,on intake stroke both will be TDC
Are there any videos to show how to find mechanical timing? I’m pretty new to this and I need my baby running again.
check your crankshaft pully for tdc and deg marks then use a timming light conn. to a plug wire and battery spin he eng see where it flashing on the pully (lower front of eng with fan belt loosen dist bolt beneath dist. slow rotate will move timming light flash if you can set about 5 deg before tdc tighten bolt under dist it should run at this setting
How should we know what the degrees should be and does timing change if not naturally aspirated
Timing changes if not NA
I have 1980 C10 Silverado 350 5.7 my vacuum advance it's almost hitting the intake manifold, my truck starts at this location. Do i have to restab,the distributor for the vacuum advance to be set properly
No...you can move your wires forward or backward on the cap to change the location of vac advance
so you have to match up the line on the belt to the mark?
These old school engines have timing chains, the crank shaft and the cam have timing marks that have to line, and when this is done, the engine will be on top dead center,
No one ever cares to mention that you are supposed to get the engine up to operating temperature before you adjust your timing
chris18228 I think that’s mainly for the choke to be off its cycle
Cold or hot no difference!
Steven L Jones maybe he thinks warming it up you can see the line better?
The engine idle is way different warmed up vs cold
You are absolutely full of shyt! Temperature has absolutely no bearing on mechanical advance and vacuum advance is disconnected. If it idles too low then adjust the idle up a little, if you have the skill it takes to perform that basic function. Everyone thinks initial timing is what matters, but it is actually total timing!
geter done
hey hagerty..i have a question...my 1988 chevy got the marked painted over...how will i know when timing is set right?
Why did you time it at 12 degrees? Those old chevy timed at 4 degrees even when my 350 was a 420 horse it was only 10 degrees... LOVE MY HAGERTY INS.
Because 4 degrees is for emissions engines. The 72 he used in the video has no emissions equipment so it will run best at about 14-16 degrees initial and 36-38 degrees total timing
Which way are you suppose to turn the distributor to advance it?
my 69 Chevrolet C10 back fires under load for example if I'm traveling on a small grade or hill in 1st? Could this be a distributor timing issue?
Or a flat lobe on your cam
Backfiring from the carb is a timing issue. Backfiring from exhaust is a rich mixture issue
My car does too! Did you fix ?
What if my distributor doesn't have a vacuum advance ? I'm brand new to working on engines but I've checked everywhere and there's no lines going to the distributor
I set mine at full advance,, and check for spark knock on take off if none your good and get most out of your engine,,, and if you really want performance run high test fuel,,,the more you can advance without preignition the better it will run,,