1991Jeep_Man

Alright, so I got a '91 Cherokee Laredo, 4.0 HO all that stuff, and I just wanted an opinion from anyone who might can help me. I had been having a whining noise come from the front pulley assemblies back in December and had it looked at by a local shop. He told me it was my power steering pump and pulley, so I paid the wonderful $250 and thought the issue was resolved. However, today as it was warm and I felt like driving to church, I heard that same familiar whistle/whine that I thought was taken care of. Even better, as I was pulling out of our lane, I heard a very noticable "POP" come from the engine compartment. No drastic oil pressure drop or anything noted so far, and the whine isn't as bad as before. Any ideas? The sound is coming from around the fan, a/c, and w/e is under the a/c compressor (alternator?). Thanks for any help.

OverlandZJ

Did you open the hood and look when you heard the pop? You may have lost your serpentine belt, you may have a bearing going in an idler pulley or something.

Sometimes these noises can be tough to diagnose as theres so many possibles in such close proximity.

Are you mechanically savy? You could carefully take some WD40 with the tip on it and spray the backside of all the pulleys as it's running to try and isolate the culprit. Watch your fingers..

1991Jeep_Man

Im basic, meaning that Im not the ultimate mechanic but also I'm not a total moron about it. I am going to try your idea for the WD40 and spray behind the pulleys as they run. Also, I dont think I lost any belts. I drove it around today and no upsets so far, and the whining noise seems to subside then quietly come back, faintly though. Thanks for the help. I'm going to check it out and see what happens.

guest02

I would try replacing your Belt with a GoodYear GatorBack. When you think you get it tight, tighten it some more. However, a loose belt still doesn't explain the "pop"!


I wasn't thinking that you were a moron either on your previous post, but the "pop" was a common noise from a broken belt. That's the first thing that i thought also.

That said... i honestly don't have a clue as to what that noise was. I just can't see anything making that kind of noise. This is a tough one to help diagnose on our end, ya know?

Sorry that i can't help from here my friend,
Please keep us posted on what you find out.

OverlandZJ

I hope you didnt read that i implied you were a moron.. sorry if you read it that way.

If you lost your belt you would have overheated shortly after.. but i'm drawing a blank at what the pop you heard could have been.

Let us know what you find..

Just remembered, a bud of mine had a time of finding a squeel, replaced a few pulleys/ps pump and it turned out to be a belt that just wanted to sing.

1991Jeep_Man

I'm sorry if I seemed sarcastic lol. I was just being my usual self, basically saying I'm not the best but not the worst. I appreciate your all's help and hope that I didn't give the wrong impression with my quote.

1991Jeep_Man

Well I'm stumped. The dang thing drives well, no hesitation or falting that I can note. I'm going to call the garage back tomorrow and see if they will take another look at it, considering I just popped them a combined total of about $300 last visit (less than a month ago) and they told me the p/s pump swap would fix it. Anyway, I will let you all know what I find out.

1991Jeep_Man

well I had it looked at today by the mechanic. They told me the noise was from waterpump bearings going out and that I will have to replace that soon. The "pop" I heard they told me was the front right coil spring popping out or something like that. They recommended I go ahead and replace them both at the same time. So awesome, another $385 out the wallet. But I guess its worth it, I love the ol' girl. lol

Tural

check the idler pulley. it shouldn't have any back and forth play in it. and if you're gonna pay that much, why don't you put on a RC 3" lift kit instead. might end up costing about the same.

superj

sounds like the stupid idler puller to me. i hate that thing. i changed mine two days ago and the new one is doing the same damn thing. i'm just going to drive it till it gets some play and then change it again.


i notice they changed the bearing size on the new idler versus whatever was on there previously. the center bushing was smaller and didn't completely cover hte seal on teh bearing like the old one did

Tural

i know what you're talking about. i'm thinking of customizing a mustang pulley for it. it's indestructible.

Borego

Air trapped in the P/S pump.

The pop could be the air pushing on the cap.

Big Mac

You can easily check if it is the belt squealing with a juice glass full of tap water... Simply pour the water on the belt while the engine is on and the squeel is present. If the squeal stops, tighten the darn belt or replace it id it is hard and cracked...

This will not hurt anything and you don't need to get out any tools. If it is a bearing, water will have no effect on the noise.

Do NOT use a "belt dressing" stick on your belt from the auto parts store. It only makes the belt sticky and the noise will return the next day.

"Let me do this one boss... I ain't never seen one of these before...!"