91 cherokee knocking at idle

[bdahlg]

i have a 1991 cherokee 4 litre inline 6. it knocks from what seems to be the bottom end of the engine. The knocking is rather inconsitent in terms of a pattern, just basically knocks and knocks and knocks. When i hit the gas, however, it stops and actually sounds like the jeep it truly is. But as soon as i let off, its back to the heartbreaking knock.

I've gotten numerus opinions such as a loose torque converter (crossing my fingers ), cracked exhaust manifold which i havent checked for yet, a rod knocking or a loose crankshaft bearing (please no). i've also heard of a faulty lifter, valve spring, piston slap, spark plugs or spark plug wires, but since i am almost positive that its coming from the bottom end, i am going to have to rule these out. Also, i have an oil leak from the pan right near the crankshaft pulley...could this be part of the problem?

Any suggestions whatsoever would be a HUGE help
Thanks

[wwwildman]

My first guess would be that you have a rod knocking and a front seal leaking.

[bdahlg]

When i listened again very very closely to where it was coming from, it sounded like it was coming from where the torque converter is located, but its just too close to everything else to tell for sure. Any suggestions?

[wwwildman]

could be the torque converter bolts are loose.

[bdahlg]

That's what i am thinking and hoping, but could it possibly be something else and is there any sure way to tell besides ripping the tranny off and tightening the bolts? Thanks for the help i appreciate it.

[AlohaBra]

You don't need to take the tranny out to tighten the torque convertor bolts.

There should be an inspection plate.

[bdahlg]

is the inspection plate the piece thats on the bell housing where the tranny connects to the engine? Torque specs? Do you think that this is a plausible remedy or too far fetched?

[bdahlg]

anddddddddd it was the torque converter bolts. They were barely finger tight. I am so incredibly happy that this was the problem. Hoping to get at least another 70,000 out of an already 152,000 running strong. Thanks for the help guys.

[danols15]

Originally Posted by AlohaBra

You don't need to take the tranny out to tighten the torque convertor blots.

There should be an inspection plate.

Can someone please give detailed instructions on how to get to the torque converter bolts? That would be great! I think my Cherokee is doing the same thing, but I am not sure how to get there.

[ya472]

If you have an automatic transmission, check for cracks in the flex-plate, around the crankshaft mounting bolts.


My flex plate was completely broken, but because of the limited space, the irregular pattern allowed the motor to drive the torque converter.

It was diagnosed by many mechanics, to be an engine problem.

Use a high intensity light and/or a mirror to view the area around the bolt heads, once the inspection plate is removed. Also check for loose crank bolts, and flexplate to converter bolts.

Replace the flex plate.

[Homer8270]

Thank You Thank You
Aloha & wildman. . .That was my mystery rattle. Runs like a New jeep now.
90 XJ Laredo. 4.0 220,000miles
I was afraid it was my Journal Bearings and was in no hurry to investigate.
My Flywheel bolts were hand tight as bdalg said.