amc 401 vibration darnnit!!!!!!!

[maccj5]

:smile: i recently put a 401 in my 73 cj5 it originaly had an automatic behind it so to put it in my cj with a t18 i bought one of those flywheels off of ebay it runs great and sounds good i took it down the street and i get a bad vibration as the rpms come up the harmonic is original to the engine my question is has anyone had this problem with these china? flywheels? or could i have cramed the pilot shaft bushing in and the pilot shaft is wobbling around? anyone have ideas other than what i expect is the problem?

[jeepsr4ever]

I have heard of issues with the cheapie flywheels. Currently their is no cheap substitute for a 401. You did make sure and install a pilot bushing right?

[maccj5]

sorry i thought by my asking about cramming the bushing in that it was clear that there was in fact a pilot bushing installed

[tufcj]

Did you change anything else? Lift? Driveshafts? CJ5 drivelines are pretty prone to vibrations.

Do you still have the automatic flexplate? You could take that and the flywheel to a performance shop and see if the balance is the same.

Bob
tufcj

[jeepsr4ever]

sorry i thought by my asking about cramming the bushing in that it was clear that there was in fact a pilot bushing installed

aahp yes sorry

[maccj5]

i found the problem i did take the flywheel and the flex plate to the machine shop the flywheel was 2 ounces out of balance