Adjusting rockers
Melting Slicks
Joined: Nov 2002
Posts: 2,884
Likes: 260
From: Jamison Pa
St. Jude Donor '11-'25
The motor should be warm. Get a set of the clips that go over the oil holes on the pushrods side of the rocker arm, or cut a valve cover to stop the oil from going all over the place.
I would start the motor. Tighten the rocker nut until the tapping stops, then slowly tighten 1 full turn. You turn the nut 1/4 turn at a time and wait a few seconds between each 1/4 turn.
I would start the motor. Tighten the rocker nut until the tapping stops, then slowly tighten 1 full turn. You turn the nut 1/4 turn at a time and wait a few seconds between each 1/4 turn.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
The only thing I would add to the above is to back off the nut until you hear it starting to click, if it's not already clicking. Then carry on with the adjustments as stated above.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You can adjust them on a running engine and you can adjust them on a static engine. One is messy and the other is not.
On idling engine, back rocker nut off until it starts clacking (free play). S L O W L Y tighten that nut until it just ceases 'ticking'. Now, tighten it 3/4 turn CW. Do that on all of them. Done.
For static engine there are several methods of rotating the engine. Some will minimize the rotation effort. The lifters also need to be primed [pumped up] with oil; you cannot set them properly with dry lifters. Submerge lifter in oil, stick end of pushrod in lifter seat and pump a few times to get oil into the lifter; then install them, pushrods and rockers.
Hold pushrod with thumb and forefinger of one hand and shake [loose] rod vertically while slowly tightening the rocker nut with wrench in other hand. When you just feel no "slop" in the pushrod, that is the 'zero free play' point. Now, tighten nut 3/4 turn CW.
There is also the 'spin' method for pushrods. But, I find this is difficult for folks doing it for the first time.
Good luck with your project.
On idling engine, back rocker nut off until it starts clacking (free play). S L O W L Y tighten that nut until it just ceases 'ticking'. Now, tighten it 3/4 turn CW. Do that on all of them. Done.
For static engine there are several methods of rotating the engine. Some will minimize the rotation effort. The lifters also need to be primed [pumped up] with oil; you cannot set them properly with dry lifters. Submerge lifter in oil, stick end of pushrod in lifter seat and pump a few times to get oil into the lifter; then install them, pushrods and rockers.
Hold pushrod with thumb and forefinger of one hand and shake [loose] rod vertically while slowly tightening the rocker nut with wrench in other hand. When you just feel no "slop" in the pushrod, that is the 'zero free play' point. Now, tighten nut 3/4 turn CW.
There is also the 'spin' method for pushrods. But, I find this is difficult for folks doing it for the first time.
Good luck with your project.
Thread Starter
Drifting
Joined: Jul 2012
Posts: 1,255
Likes: 297
From: Slovenia, EU
2017 C3 of Year Finalist
Will try to do it on the idling engine.
I get siking like noise from the engine and don't know if that is normal or not. It sound like an old air cooled VW Beetle. I don't have exhaust leak as far as I know.
Also the the fan noise is quite obvious. Is it possible that the fan clutch is to blame?
I get siking like noise from the engine and don't know if that is normal or not. It sound like an old air cooled VW Beetle. I don't have exhaust leak as far as I know.
Also the the fan noise is quite obvious. Is it possible that the fan clutch is to blame?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Check the heat riser valve on the outlet of the right side exhaust manifold. The valve should be free to move; but many get corroded and freeze in place. If it locks up in "closed" position, there is a lot of exhaust back pressure built up and it sounds like what you are describing.
This is a significant problem. You don't want to run the car hard or on the highway if that valve is locked in closed position. Because of the risk, I have opened up that item and cut the valve off of its shaft so that it can't close on me again. It is only of benefit in very cold weather (when I don't use the car) anyway.
This is a significant problem. You don't want to run the car hard or on the highway if that valve is locked in closed position. Because of the risk, I have opened up that item and cut the valve off of its shaft so that it can't close on me again. It is only of benefit in very cold weather (when I don't use the car) anyway.
Thread Starter
Drifting
Joined: Jul 2012
Posts: 1,255
Likes: 297
From: Slovenia, EU
2017 C3 of Year Finalist
Check the heat riser valve on the outlet of the right side exhaust manifold. The valve should be free to move; but many get corroded and freeze in place. If it locks up in "closed" position, there is a lot of exhaust back pressure built up and it sounds like what you are describing.
This is a significant problem. You don't want to run the car hard or on the highway if that valve is locked in closed position. Because of the risk, I have opened up that item and cut the valve off of its shaft so that it can't close on me again. It is only of benefit in very cold weather (when I don't use the car) anyway.
This is a significant problem. You don't want to run the car hard or on the highway if that valve is locked in closed position. Because of the risk, I have opened up that item and cut the valve off of its shaft so that it can't close on me again. It is only of benefit in very cold weather (when I don't use the car) anyway.
Is this relevant for me, since I have hooker long tube headers and hooker exhaust system?
I don't have heat riser valve on the exhaust manifold.
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Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy