I am not a pro at this so thought I would post to get some input. Posted this on a camaro forum too but figured this is issue isn't specific to vehicle make. Have a 73 Z28 with M21. Have had the car almost a year. Always thought it vibrated too much and gets worse with higher RPM. I was thinking it was flywheel / pressure plate causing it. Is it possible to have the flywheel / pressure plate checked for balance? I pulled the engine and tranny out this past weekend and disconnected the transmission today. Have not loosened the flywheel or pressure plate bolts yet. Even thought about starting this engine to see if I could visually check for an imbalance. Any thoughts? Attached a few pics if that helps.
Do you know if the bell housing is indicated in properly? I know alot of people think you can slap it on and the dowels will be perfect, but that's not the case. Sometimes you get lucky, sometimes you need eccentric dowels. http://www.robbmcperformance.com/products/dowels.html
Things don't look centered but that may the camera angle. It also looks like the pilot bushing has an off-center wear mark. Was the transmission flush against the bell housing, meaning the pilot shaft fully seated? Since the tranny is out remove the clutch and pressure plate to check their condition then put just the bell housing back on and check the crank run out with a dial indicator. Unless that motor is factory stock you can't assume the crank center line is within spec to the transmission input shaft center line. I think the tolerance is +/- .005 but double check. If it is out of spec you'll need offset dowel pins. Now is a good time to replace the pilot bushing too.
Thanks fellas. I have never assembled the pressure plate/ flywheel / clutch before, only removed. I'm afraid I'll get something wrong when I reinstall. Anyway I too noticed a slightly off center wear pattern on the pilot bushing. I will check the alignment with bell housing only installed. I have not yet pulled the pressure plate/clutch or flywheel yet. Was waiting on some responses. I was hoping to find something loose that was causing an imbalance but guess not. Is it possible to take to a shop to check balance of my flywheel and pressure plate?
How is this actually performed? where do I measure? Also, got the flywheel turned and balanced. Was off 31 grams I think. Drive shaft is being replaced too. It was bent.
Page 2: http://documents.holley.com/lakewood_instructions_safety_bellhousing_pontiac_oldsmobile_15100.pdf
"Drive shaft is being replaced too. It was bent." Your new driveshaft will cure some off your vibration issue. I hope the shop balancing your flywheel did not create a "new" vibration. Allen
