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Valves adjust

Old Sep 27, 2021 | 04:36 AM
  #1  
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Default Valves adjust

Hello,

I would like to adjust the distance between the valves and the rocker arms.

Can you confirm to me that it is good value that must be used ? I have the HAYNES book but I can't find where the procedure is explained, what's the name in English please?

thank you very much and good day





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Old Sep 27, 2021 | 05:15 AM
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Valve lash adjustment

98% of c3 Corvettes use hydraulic tappet lifters on the cam requiring 0 lash plus a partial extra turn

Only the highest performance motors have solid tappet lifters requiring a valve lash gap like your picture
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Old Sep 27, 2021 | 05:22 AM
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ok so is it normal that i am not gap ?
do you have a picture of what a hydraulic lifter is?
i don't know what i have on my engine.
tanks !
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Old Sep 27, 2021 | 05:24 AM
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I checked your profile trying to find info on year of car, engine, etc. No information in your profile. Guessing by your user name you have a 79. If you have the original engine. I would lash them at zero plus half turn down.
If you have a different engine or one that's highly modified. Perhaps you need to fill us in.
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Old Sep 27, 2021 | 05:25 AM
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It is normal that you have no gap
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Old Sep 27, 2021 | 05:36 AM
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Just 2 more things.
First, get a Genuine G.M. service manual. Worth its weight in gold.
Second, You have a car and know nothing about the engine in it? You sound like some of the women I have dated! Post up a photo of the stamp pad on the front of the block just in front of the passenger side head. thou numbers on there will help us help you as to what the engine at least started out as.
If it were me I'd tear that thing down to a bare block. I would want to know!
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Old Sep 27, 2021 | 06:06 AM
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thank you for your answers.
here it is not easy to know the history of my car. It's only been a month since I bought it. i updated my profile, it's 74, 79 it's my year of birth.
I'll try to find the documentation you recommend.
here is the photo of engine number.
have a good day



.

Last edited by alexandre1979; Sep 27, 2021 at 06:11 AM.
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Old Sep 27, 2021 | 07:10 AM
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Originally Posted by alexandre1979
thank you for your answers.
here it is not easy to know the history of my car. It's only been a month since I bought it. i updated my profile, it's 74, 79 it's my year of birth.
I'll try to find the documentation you recommend.
here is the photo of engine number.
have a good day



.
CLA comes back as: 1974 350 4bbl. 195hp TH400 trans. It has hydraulic lifters. There is zero lash and it must be set with a lifter preload. I set them at zero lash and one half turn as others have stated on the forum.
E-Mail our member Lars, I believe he has a valve lash paper he can send you to read. You can get him at: V8fastcars@msn.com

Jebby
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Old Sep 27, 2021 | 08:11 AM
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We used to do it with the engine running back it off till it clatters then tighten the nut till it stops clattering then turn it 3/4 turn tight
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Old Sep 27, 2021 | 09:12 AM
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Originally Posted by alexandre1979
ok so is it normal that i am not gap ?
do you have a picture of what a hydraulic lifter is?
i don't know what i have on my engine.
tanks !




Originally Posted by ralphspears
We used to do it with the engine running back it off till it clatters then tighten the nut till it stops clattering then turn it 3/4 turn tight
Some guys would cut holes in an old valve cover to adjust while running. I still have my oil stop clips.
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Old Sep 27, 2021 | 09:36 AM
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Here are some of the clips for adjusting valves with engine running
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Old Sep 27, 2021 | 12:33 PM
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Originally Posted by ralphspears
We used to do it with the engine running back it off till it clatters then tighten the nut till it stops clattering then turn it 3/4 turn tight
I mentioned this a few months ago as "A" way to adjust the valves and got some static from some experts here. I never said it was the best or easiest, but I do believe it gets good results. Especially for someone without much mechanical experience or the finesse to figure 0 lash.. This is the way it is explained in the early '60's Motor Manual's, which were the bible back then. It could be messy, so watch out.
Engine should be hot when doing this.
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Old Sep 27, 2021 | 12:36 PM
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Why do you think the valves need adjusting ??
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