Belt Squeak/Chirp~Cannot figure out

[Lake919]

Hi guys so my 4.0 has developed a very annoying Squeak/Chirp and it is loud and high pitched and super annoying. SO this morning with the hood open and then engine running I sprayed soapy water directly on the top of the belt at the AC compressor and the noise disappears until the water dries and then its right back to annoying nails on a chalkboard again. Is this bad belt(it looks new) or is the single pulley to the right of the compressor going bad or is it something else? Any advice will help.

Also how do you take a belt off an XJ?

 

[Lake919]

Ok so after some more toying with it, my GF and I both agree its a chirp and it increases as I give it throttle

 

[ehall]

Do you have any 1/2" hose? 2-3 feet of that, one end jammed in your ear, will tell you exactly where noise is coming from

The belt tensioner pulley is attached to the power steering bracket. Loosen the bolt holding the pulley, then crank the long bolt to adjust tension. Its a pretty clumsy setup on the 91-95 models, somewhat less clumsy on later models.

Do you have a NAPA near by? You should really really really buy a KR2 tensioner gauge

If its just idler pulleys, you can pop the seal off the bearing with an xacto blade and clean/lubricate pretty easily, or buy new Dayco pulleys from advance pretty cheap

 

[Lake919]

Yeah there are several napa stores nearby, the issue is they are all closed on Sunday. I really need this fixed today, I guess I will buy new idler pulleys as they are cheap and go that method. I would like that tensioner gauge but have no way of buying it today

 

[Lake919]

Ehall any idea on the torque spec for the idler pulley bolt?

 

[ehall]

Nope sorry I always use that gauge. Worst case I will get it so that I have to use full hand strength to fully twist the belt at the long span

 

[IslanderOffRoad]

if you buy new idlers and dont tighten the belt enough, you'll still have the issue, and be mad that you threw money at a problem and didn't fix a thing.

Wait a day, get the tensioner, try that. I had a shop replace the a/c compressor on my XJ and they didn't even tighten the belt properly. Start there.

 

[Lake919]

Ok its fixed, before getting the belt off I realized the PS pump pulley looked tweaked at an angle, after loosening the belt and going to move it, the pump and pulley jumped to the right aligning everything. I tightened everything to spec and started it up with zero squeal or chirp

 

[Matthew Currie]

Just as a general heads-up, the belt tension on these when it's right feels very very tight. If you test it with the correct gauge (as you should) you'll be surprised at how tight it must be. As a stopgap, you can use the "twist" method. Find the longest unsupported span of belt, and attempt to twist it. If you can get it past 90 degrees it's probably too loose. That's a very coarse approximation, but it is a start.