more squealing

recently replaced the waterpump <1 yr ago

replaced idle pulley that sits where the ac would have been. Got it from Napa though it's smaller than stock, and I had to put in a washer to make it work.

now it's quiet but once it warms up it chirps and squeals and is quicker and louder as the rpms go up.

when it's cold, it's perfect.

I have tightened the belt as far as the bracket will allow. all the pulleys run straight, no wobbles. turned each one by hand, none provide any inconsistent resistance. no play in any that I can detect.

new gatorback belt.

At a loss for what it can be.

Are there any other tests I can try?

it's a 91 xj no ac 4L. stick. 200k.

tried a search, all the ones I found seem to chirp during warm up.

please?

bump

try replacing the bearing in the pulley? its only a couple bucks.

Did you carefully check the harmonic balancer, front and back, to make sure no rubber is beginning to protrude?

2nd the harmonic balancer.

Do you have a Krikit2 belt tensioner to measure the belt tension? Could the belt be too long and not tight enough?

I am currently trying to track down a similar squeal in my '91 XJ 4L w/AC.

Replaced water pump and idle pulley. Squeal went away for about 3 days then back again.

Every time I pull the belt to inspect all the pulleys (no resistance on any) the squeal will go away only to return a day or two later!!! :flamemad:

First I would spray each pulley one at a time to try to determine if its a Pulley.
Stethoscopes (or a rubber hose ) can also be used to try to find the source of the noise but be VERY VERY careful
Second I would try spraying a generous application of Belt Dressing.

If you have your Adjusters are maxed out it, its possible you have a belt one size to big.
Water Pumps have been known to go out in as little as a few months.

funpolicexj said:

replaced idle pulley that sits where the ac would have been. Got it from Napa though it's smaller than stock, and I had to put in a washer to make it work.

Click to expand...

Is the pulley itself smaller, and why did you have to use a washer and where did you put it?