87 4.0L XJ belt?

OK something stupid yet driving me nukin futs, lol. The belt keeps walk ing to the rear of the fan pulley, and squealling against the timing cover. I have replaced everything but the fan pulley is used. New so far (cause they were worn) alt, a/c mount with fan shaft, belt, idler pulley, h20 pump, and used h20 and fan pulleys. I finally got jacked and cut the last rib off the 6 rib nelt and it dont squeal no mo, but I'd like to get to the bottom of it. :dunno:
thanks

!!!1

I bet your harmonic balancer is worn. That is the problem 99% of the time with XJs that throw belts.

mine is doing this too. Well it only threw a belt when I sprayed belt stuff on it and it seems that no matter how tight I get it it squeaks like a .... (non pc analogy of your choice here).
Is there a way to test this without throwing parts at it?
I did notice when I oiled the idler pulley the noise went away but it could have been overspray...

check your belt for glazing.....

Mine did the same thing. It started eating belts about every hundred miles or so. I was out of town and wife had 2 belts installed while I was gone and the second was frayed by the time I got home. (Left the XJ with her while I was gone.) When I pulled the second belt to see why it was fraying I found the water pump pulley was a little wobbly on a new pump (less than 5000 miles) so I replaced the pump and put on a new belt and that was the beginning of the summer. Now 6 months later and no problems so far.

Mine did the same thing, I did all the same things you did. It was the harmonic bal. Replaced it (took about 2 hours) problem solved. At Auto Zone it was $47.00 and a free puller.

bassthumb said:

mine is doing this too. Well it only threw a belt when I sprayed belt stuff on it and it seems that no matter how tight I get it it squeaks like a .... (non pc analogy of your choice here).
Is there a way to test this without throwing parts at it?
I did notice when I oiled the idler pulley the noise went away but it could have been overspray...

Click to expand...

Inspect the belt drive pulleys. Look at the crank pulley, if it looks like the pulley metal will rub against the engine, it is bad. There are 2 parts to this pulley. The outer ring starts to come off of the inner hub when the rubber that joins the 2 parts fails. You might notice this rubber cracking or squishing out from the pulley.

When the harmonic balancer fails, it "walks" towards the engine pulling the belt into the block between the fan pulley and the harmonic balancer.

Don't hold off on replacing the harmonic balancer, it can hit the timing cover and wear a hole into it.

thanks, I'll take a close look at it. after reading another post on the tension, I went and gave it a few more turns on the adjuster and if anything, I over tightened it now. Have the gauge on order to check for sure...but the squeal is gone except for when I begin accelerating.