Guys I need some input, my blown 302. Son was driving a couple of weeks ago and at 45 mph in high gear , car stated shaking really bad. He nursed it home and we did a quick evaluation. all belts pulleys ect seemed to be normal, no valve train issues, motor sounds perfect, no misses, sputters. pops, backfires, etc even through a stethescope. Engine wise everything sounds and seemed normal. Violet shaking thru the steering wheel/entire car , even in neutral on jackstands. Very symptomatic of the bad converter in my Shelby a year or so ago. We pulled the tranny, no bad chunks or debris noted in pan, no visable damage or missing weights from flywheel, and I replaced the coverter with a new ATI. Everything back togeather and same story. Violent shaking at idle and on up thru 2500, continues past this point but more "refined". I haven't pushed it past this point , see no need to. Today , disconnected the blower and still there, so not blower related. maybe damper? Promac brand, dont know if its a fluid damper or not. How can I tell, or test this theroy ? This is a very bad shake, not just a vibration. NO broken motor mounts. Any other thoughts or suggestions woule be appreciated. Don't want to just start replacing parts until the problem goes away.. Thanks, Steve PS- pulled tranny and put bellhousing back on and fired it , same thing. tried palying with dizzy, no change. Pulled all belts and blower pulley/spacer..no change....aghhhh
Yes look at the damper/crank pully.. It sound like you may have sheared the keyway... Or you jumped time... I had that happen, it would run but popped and shuddered???
Damper may have shifted on hub knocking it out of balance.Easy check:bring #1 piston to TDC according to balancer,pull dist cap.If the rotor aint pointing to #1 and you knwo the timing is good,balancer shifted.If its one piece balancer, 500GT steve is right.Not an uncommon occurrance with a blower on any engine to shear a key.Other wise I would say you have a crank thrust bearing issue.Good luck.
Broken crankshaft, split mains/block, pry the crank back and forth to check the wear on the center thrust bearing. Usually they will not vibrate until the lateral is so bad it breaks a rod and grenades the engine. Been there, done that. Cut the filter open and look for trash/metal etc.
