I'm still new to the Jeep thing....Having always owned sports cars and the like... I'm still working out some known problems with my 98 2wd xj, but I was wondering what to keep an eye out for while doing these other repairs... are flywheels problems on 4.0L's?... I noticed some slack somewhere in there while replacing my torque converter bolts..(don't ask). It sounds like it's knocking when running, but there is no slack on the rod bearings, or mains. I could turn the flywheel about 2 in. without moving the balancer on the front.
Any help from you Diehard Jeep guys would be greatly appreciated.

 

Hello Wewsel,

This is weir you said you can turn the flexplate 2 inches while the balancer dont move are the torque convertor bolts too long?
How are the splines on the t convertor?
Your oil pressure should be very low if the mains/conrod bearing were that bad.

 

Most common failures? Hmmm...
Crank Posion Sensor
Cam Position Sensor
Throttle Position Sensor
Idle Air Control
MAP Sensor
O2 Sensor
Dirty Nuetral Safety Switch

 

.....hub bearings
u-joints
upper shock bolts
AC
power windows

 

power steering hoses

 

Where is the knocking comeing from is it in the lower part of the engine or is it in the rear. also did you possibly lose a nut or bolt?

 

was replacing the torque converter bolts because of an engine swap from before I bought it, they backed out on the previous owner and were replaced with some from home depot, just a tad too long. like I said the crank wasn't turning but I could turn the flywheel about 2 ins.... Sounds wierd to me too.... guess I'll just wait till it goes out or I have some extra money and time to drop the trans and inspect.....On the oil pressure thing, That jumps around... Sometimes 0 sometimes 40.... Just something else I need to check into... Hoping it's a bad pressure sensor....

 

The '92 I had was making a knocking and the noise was coming from several fractures of the flexplate itself. I replaced the flexplate and low and behold the knocking stopped. It had good oil pressure and the crank journals were plastigauged out to be within specs.
Do not use Home Depot bolts in a flywheel/flexplate in the future. Use grade 8 bolts or ARP crankshft bolts. The Home Depot stuff is not up to that kind of job.

 

it was a temp fix to get her off the side of the road for the girl who had it before me....they were still holding fine, just too long... I used loctite when I put them in....