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Good news! The machine shop called today. They said the heads are all good and ready to go. Now for the fun part....adjusting the rocker arms. I know theres probally a few different ways to do this but can I adjust the rocker arms by going off the cam lobe and lifter....for example lets say i look at the camshaft and lifters and find the open valves and adjust the opposites and turn the crank and keep doing this until the valves are done?
theres a sticky in the 'Sticky's up at the top of the page that describes this pretty well. you'll get 14 versions down here, they'll all work, but the sticky will keep you from getting confused.
Better to go too loose first time around than too tight....its easy to go back and add 1/2 turn...
Take your time and don;t rush it.
I always spin the motor over with the starter and dist disconnected after a major adjust so I can watch the rocker action and look for a problem before its serious. After a few seconds of cranking you can go back and spin random rods to check yourself. Nice to have a couple spares laying around too...
thank you for the video and other links! They are very helpful. Ill be picking the heads up tommorow and hopefully have the car on the road tomorrow night or the next day!!! Ive missed driving it so much. Is anybody on here coming out to the corvette weekend in Ocean City Md in october?
Adjusting valves on the 1985 Corvette, same as the 1987:
1) Remove the spark plugs. This makes it much easier to turn the engine by hand.
2) I believe that the nut in the center of the bottom pulley on the balancer is 5/8”. Use a six point 5/8” socket to turn the engine over by hand to line up the timing marks. Place a finger in the spark plug hole for plug #1 as you turn the engine over. You are trying to determine if the engine is on compression as you line up the marks. If you feel the air pushing against your finger as you line up the marks, you have compression in cylinder #1. Align the timing marks.
3) Now adjust the valves as follows:
Intake #1, 2, 5 and 7 then adjust Exhaust 1, 3, 4 and 8.
4) Turn the engine 360 degrees and line up the timing marks again. Now adjust the following:
Intake 3, 4, 6 and 8 then adjust Exhaust 2, 5, 6 and 7.
You are now finished with your adjustment. I usually tighten the lock nut ½ turn after adjusting to zero lash.
Here is a modification to the twisting the push rod method that I have used for over 40 years. This comes directly from Forum Member JoeC and I find that it works great. From his post:
BTW, I tried something a little unconventional on adjusting hydraulic lifters. One thing that always bothered me is the statement "spin the pushrod until resistance is felt" that seems a little too subjective to me. So I tried this: I set "zero" lash with a .0015" feeler gauge while slowly turning the adjusting nut. (He places the gauge between the top of the valve stem and the rocker.) When I felt the feeler gauge grab, I was fairly confident I was about .001 from zero lash. At that point, I turned the adjusting nut 3/4 turn. I recently read that one turn is equivalent to .040" because of the thread pitch on the threaded rocker arm stud, so 3/4 turn should give you about .030" adjustment. I also read that within a hydraulic lifter there is .060 total plunger movement, and ideally you want to be just about in the middle of that range, or .030 inch. I don't know if I’m out in left field on what I did, but I feel I got a really consistent valve adjustment across the board. if you think you might have a tight cylinder, maybe give this a try - it seemed to work for me... - JoeC
Give Joe's method a try, you will be happy with the results.