Ruined valvetrain on a 350?

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Darth Plasma

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I adjusted my valves on my 350 TBI the other day, set it to #1 TDC and tightened the specific valves down according to the Haynes repair manual and rotated it 180 and did the other set. I tightened until i felt a drag when rolling the push rod between my fingers and then tightened an additional 1/2 turn. Engine runs smooth, no odd noises coming from engine except it shakes bad at idle and the exhaust has a bad ticking, but oddly I can't hear it from the valvetrain itself. Did I tighten them too much? Can I loosen them and be ok?
 

Arkansas_V8

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I have always wet set them. I did it proper once, didn't wanna idle and was a pain to start. Wet set them and never had a problem again. Been doing them that way since then.
 

Frankenchevy

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If you have any collapsing lifters that won’t stay pumped up, you can set too much preload. Setting them with the engine running may keep them pumped up, but not for sure.
 

Darth Plasma

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I'm gonna try setting them with the engine running, it looks much easier and better to spot an issue. I read somewhere else that the exhaust tick was tightening them down too much so maybe i'll go only 1/4 at a time
 

75gmck25

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If you set them with the engine off, instead of spinning them you should pull the pushrod up and down to check for clearance. Spinning it makes it hard to estimate, especially when they have a good coating of oil. Pulling the pushrod up and down gives a better estimate of zero clearance.

Bruce
 

yevgenievich

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Too tight. As mentioned above, should be adjusted with up/down play when engine is off. When running, loosen untill rattle, go back to just where rattle stops and then add preload.
 

Snoots

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I'm gonna try setting them with the engine running, it looks much easier and better to spot an issue. I read somewhere else that the exhaust tick was tightening them down too much so maybe i'll go only 1/4 at a time

Get ready to get oily! They do make little clips that go onto the rockers that keep oil from spraying everywhere.
 

Darth Plasma

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I had quite the oily experience I figured I was gonna have, but I fixed it! I backed them off until a clatter, tightened them until it went away and then set preload. Runs like brand new! Smooth and quiet. Thanks everyone!
 

Goldie Driver

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I had quite the oily experience I figured I was gonna have, but I fixed it! I backed them off until a clatter, tightened them until it went away and then set preload. Runs like brand new! Smooth and quiet. Thanks everyone!

Awesome! Tougher to screw one up than thought, huh ?

:)
 

shiftpro

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When installing a new flat tappet cam, it helps to set them dry, not pumped up. Then the cam gets a reduced load upon start up. But setting them dry takes a very light and steady hand but can be done with great results.
 

Darth Plasma

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350/SM465
When installing a new flat tappet cam, it helps to set them dry, not pumped up. Then the cam gets a reduced load upon start up. But setting them dry takes a very light and steady hand but can be done with great results.
Good info to know if I ever build an engine for it someday, thanks!
 

Snoots

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I had quite the oily experience I figured I was gonna have, but I fixed it! I backed them off until a clatter, tightened them until it went away and then set preload. Runs like brand new! Smooth and quiet. Thanks everyone!

Your prize for a job well done!

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