Rockers... Again
Thread Starter
Racer
Joined: May 2004
Posts: 301
Likes: 2
From: Boca Raton Fl
Rockers... Again
Okay here is a close up
Are these nuts with the allen locks after market?
I hear talk of pressed in rocker bolts, but these look threaded.
I have had 4 rockers whose jam nuts were still tight and holding in place but the space (lash) in between rocker and valve, you could slide in a dime. It was a bit noisy.
Today on the way home after running 3000 rpms for 15 minutes on interstate... a hell of a racket happened inside right valve cover. Shut her down and opened it up to see one rocker with a quarter inch of play. Made adjustment and got home, Much quieter now of course.
Questions:
1. Shop Manual says after tightening just firm make another 3/4 turn on the bolt. Is this correct? I thought there should be a feeler gauge space between.
2. Is there a way to check or tell about a cam problem without pulling cam out?
3. Also what is the little clock on the head? Time or month built?
Are these nuts with the allen locks after market?
I hear talk of pressed in rocker bolts, but these look threaded.
I have had 4 rockers whose jam nuts were still tight and holding in place but the space (lash) in between rocker and valve, you could slide in a dime. It was a bit noisy.
Today on the way home after running 3000 rpms for 15 minutes on interstate... a hell of a racket happened inside right valve cover. Shut her down and opened it up to see one rocker with a quarter inch of play. Made adjustment and got home, Much quieter now of course.
Questions:
1. Shop Manual says after tightening just firm make another 3/4 turn on the bolt. Is this correct? I thought there should be a feeler gauge space between.
2. Is there a way to check or tell about a cam problem without pulling cam out?
3. Also what is the little clock on the head? Time or month built?
Thread Starter
Racer
Joined: May 2004
Posts: 301
Likes: 2
From: Boca Raton Fl
Originally Posted by Gordonm
Those are definitly aftermarket nuts. Is the cam a Hyd. or a solid cam. Solid should have some clearance. Hyd will not have clearance. The 3/4 turn depends on the cam and manufacter.
Last edited by superdad60; Feb 26, 2005 at 07:09 PM. Reason: typo
Melting Slicks
Joined: Nov 2003
Posts: 2,362
Likes: 1
From: San Antonio TX
I am sure others will chime in. But in my humble opinion I would take those off and go to a Chevy Dealer and purchase stock nuts to put on instead. With those type of nuts you usually have to have the studs machined to a flat surface for the nuts to retain tension correctly.
Also no feeler gauge as it seems you have a hydraulic cam so it is normal that when you adjust the lifters of which I like to do running you bring them down just till the noise stops and then go 1/2 to 3/4 turn more. As mentioned before depending on cam.
As for the clock I have no idea unless it moves lol.
Also no feeler gauge as it seems you have a hydraulic cam so it is normal that when you adjust the lifters of which I like to do running you bring them down just till the noise stops and then go 1/2 to 3/4 turn more. As mentioned before depending on cam.
As for the clock I have no idea unless it moves lol.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Originally Posted by SHAKERATTLEROLL
I am sure others will chime in. But in my humble opinion I would take those off and go to a Chevy Dealer and purchase stock nuts to put on instead. With those type of nuts you usually have to have the studs machined to a flat surface for the nuts to retain tension correctly.
Also no feeler gauge as it seems you have a hydraulic cam so it is normal that when you adjust the lifters of which I like to do running you bring them down just till the noise stops and then go 1/2 to 3/4 turn more. As mentioned before depending on cam.
As for the clock I have no idea unless it moves lol.
Also no feeler gauge as it seems you have a hydraulic cam so it is normal that when you adjust the lifters of which I like to do running you bring them down just till the noise stops and then go 1/2 to 3/4 turn more. As mentioned before depending on cam.
As for the clock I have no idea unless it moves lol.
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Le Mans Master
Joined: Nov 2004
Posts: 6,128
Likes: 21
From: North Alabama
I've had this same problem recently on a fresh motor. I believe the stock nuts are a type of "lock nut". Once they have been taken off and on a couple times, the "lock affect" seems to go away. Some have said they can only be used a couple times. I will be purchasing new nuts myself. Others have said you can take a punch and hammer to the top of the nut (which I believe makes the nut edge irregular) and it should start locking in place again.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
You can pull one of the nuts off and see if the stud head is flat. You really need to find out if that is a hyd or solid cam in order to adj it correctly. I assumed I had a hyd cam and after I had a piston blow I found out it was a solid cam, I was try to use the hyd lift adj tech so I might have been the cause of the piston exploding. When I adj the lash for a hyd cam using the locking nuts I tighten the nut about 3/8 turn once the chatter stops, tighten the set screw nice and snug then turn the nut another 1/8 turn, this really gets them tight, I had been just tightening the set screw and have had a few come loose but none since I used this method.
If it turns out you have a solid cam you might be able to use the same method but you will have to make sure you tighten the nut and recheck the lash with a feeler gauge.
Those locking nuts are a step up from the stock nut so I am not sure why you would want to put stock type nuts on there.
If it turns out you have a solid cam you might be able to use the same method but you will have to make sure you tighten the nut and recheck the lash with a feeler gauge.
Those locking nuts are a step up from the stock nut so I am not sure why you would want to put stock type nuts on there.