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Adjusting valve lash after engine break-in ?

10658 Views 26 Replies 8 Participants Last post by  Fred Mann
I have about 20 minutes runtime on my new engine, just changed the oil for the first time today.

The oil had a few very small metal shavings in it, all stuck to the magnetic oil drain plug.

I started the engine after the oil and filter change and noticed a ticking noise on the driver side, sounds like a loose rocker.

I adjusted the rockers during the engine build: zero lash plus half a turn. these are hyd roller lifters.

I assume it's normal that I have to adjust the rockers again after the first 20-30 minutes runtime ???
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You should never have to readjust hyd lifters after proper initial preload was set.
you can re-adjust your rockers. if you have screw in stubs, make sure they are not walking out. also make some scribe marks on your rocker nuts and studs, this will let you know if the nuts are backing off. i like setting lash with the engine running on hydraulic lifters. i use an old stock cover that has the top cut out of it. this controls oil splash and lets you reach all the nuts. back them off until they tick, then tighten until the tick goes away and give it another 1/2 turn. this will give you 1/2 turn pre-load on the lifter.
I agree with AKRAY4PLAY. After I built the motor on my '72 Nova I started it and re-adjusted the rockers. Had lots of clicking. Not unusual to have one or two that aren't quite right. After that, you should be okay. :thumbsup:

DD
Typically after a proper installation the hydraulic lifters should accommodate to achieve zero lash. But, I wouldn't say it is ab-normal to have to adjust them one time after break in. If after you adjust them you continue to hear that noise, I would start worrying. :thumbsup:
Look at it this way, if the lifter was on the base of the cam and preloaded a half turn, this puts the pushrod about .075 into the lifter @ 0 lift.
If after break-in something in the valvetrain has worn more than .075 you got problems :(
I'm getting worried ..... :lookinup:

I'll pull the valve cover tonight and inspect
I wouldn't worry. Murphy Factor says out of all those rockers one of them will probably be a little out of adjustment. ;)

Now about those freakin stars in your avatar. :WTF ?????
I wouldn't worry. Murphy Factor says out of all those rockers one of them will probably be a little out of adjustment. ;)
That very well could be...but understand the odds of that is directly proportional on the skill of the adjuster ;)
That very well could be...but understand the odds of that is directly proportional on the skill of the adjuster ;)
That means it is likely that I have to re-adjust :thumbsup:

I think.... maybe.....
Now about those freakin stars in your avatar. :WTF ?????

I was wondering how long it takes for someone to notice...... :laughing:
I was wondering how long it takes for someone to notice...... :laughing:
You must be a POST HOG!!! :laughing: :laughing:

BTW...do you also have Spyder Lights on your Vette? :smack
You must be a POST HOG!!! :laughing: :laughing:

BTW...do you also have Spyder Lights on your Vette? :smack
I just ordered the cross drilled brake lines to match my rotors....
I just ordered the cross drilled brake lines to match my rotors....
just make sure you weld 3 flexplates together to make a flywheel. :rolleyes:
This is annoying: I re-adjusted the rocker arms, 6 were loose...... the tapping noise was gone for about 5 minutes, now it's back... :thud: :thud: :thud:

I think it was not the greatest idea to use the stud girdle to lock the rocker arm nuts..... this does not work very well.....

tomorrow I'm going to adjust one more time and use regular self locking nuts instead :thumbsup:
just make sure you weld 3 flexplates together to make a flywheel. :rolleyes:
I only have two flexplates, need one more to make a flywheel..... I am not sure if mine a re clocked correctly so don't have a clue if it's going to be a 153 or 168 tooth flywheel when I'm done.... maybe I can return it and get one that fits ??? Actually.... wait.... I don't need a flywheel so i don't have to return it.... maybe ?????
This is annoying: I re-adjusted the rocker arms, 6 were loose...... the tapping noise was gone for about 5 minutes, now it's back... :thud: :thud: :thud:

I think it was not the greatest idea to use the stud girdle to lock the rocker arm nuts..... this does not work very well.....

tomorrow I'm going to adjust one more time and use regular self locking nuts instead :thumbsup:
Sounds like a good plan. Keep us informed!! :thumbsup:
SOmeone, I forgot who, put a stud girdle on a BB and found it was changing his valve lash by a pretty good bit. Enough to be concerned with. Seems the stud girdle was slightly mis-drilled and was deflecting the studs. HE ended up doing some maching work to the girdle so it was actually functional. My feeling is that unless you're running a cam that's in the stratosphere for lift a girdle is an extra piece.

Is your girdle pulling your studs to the point it's causing your carefully set valves to be incorrectly adjusted? ANd an aluminum girdle will expand at a different rate than the heads and may make it worse..

:cheers:
try some locking nuts like these http://www.shop.com/op/sprod-0-p30235762-k24-g1-~crane+rocker+nuts-nover . you should not re-use stock style rocker nuts and never ever ever use a nylock nut. i am a fan of the posi-lock nuts, they will hold even if the studs are worn down a little from multiple threadings of stock style nuts. at least you found the problem and it's a simple fix!
This is annoying: I re-adjusted the rocker arms, 6 were loose...... the tapping noise was gone for about 5 minutes, now it's back... :thud: :thud: :thud:

I think it was not the greatest idea to use the stud girdle to lock the rocker arm nuts..... this does not work very well.....

tomorrow I'm going to adjust one more time and use regular self locking nuts instead :thumbsup:
I have a Crane stud girdle that I haven't been able to use due to clearance issues with the valve cover baffle even though I have tall covers. The instructions say that repeated adjustment of the valves is required initially. Although that doesn't explain why the noise went away and then came back. Pressed in studs on the head?

I'd take the stud girdle off and re-adjust the valves to eliminate the girdle from considerstion as the cause. Maybe that's what you have in mind already. If this is a hydraulic roller cam, you shouldn't have to worry about any cam break-in issues.
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