NAXJA Forums -::- North American XJ Association  

Go Back   NAXJA Forums -::- North American XJ Association > NAXJA Unibody Jeep Technical Forums > Jeep Cherokee XJ (1984 - 2001) > OEM Tech Discussion
HOME Member FAQ Sponsor Info Rules Bylaws E-Mail

OEM Tech Discussion Forum for OEM (Original Equipment) or stock XJs and MJs.

Reply
 
Thread Tools Display Modes
  #1  
Old March 4th, 2007, 17:13
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Weird Squealing Noise...

Hi,

88 xj with reman 4.0L not even 7k mi on it since installed, reman aw4 tranny, new 170Amp HO Alternator for Computer/GPS/AV System.

My xj stays in the garage most of the time and I only start her about 1-2 every 2wks just to keep the battery charged.

Today, I went to start her and she fires right up as usual but I noticed a low-pitched squeal that gradually gets louder as I let her warm-up. I popped the hood and the squeal definitely is coming from the front of the engine.

The squeal goes away if I rev the engine a little but when I let it idle it comes back.

I searched and found: may be the belt (new belt no glazing and tight only around 1/2" deflection with thumb pressure, harmonic balancer, or water pump (no overheating and could it be bad at only 7k mi?)), bad alternator (new), bad a/c compressor (a/c blows cold).

Which of these and any others that I might be missing could be causing the squeal that goes away when I rev the engine? Could this squeal cause any damage to the engine? What can I do to stop it squealing or how do I fix it?

Thx. Phil
Reply With Quote
  #2  
Old March 4th, 2007, 23:51
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Re: Weird Squealing Noise...

Hi,

Can someone please help?

Thx.
Reply With Quote
  #3  
Old March 4th, 2007, 23:58
ECKSJAY's Avatar
ECKSJAY ECKSJAY is offline
Water is dirty
 
Join Date: Jun 2003
Location: Covington, WA
Posts: 13,008
Re: Weird Squealing Noise...

Check the idler pulley. Those are often overlooked. My squeal a few months ago fit that description and turned out to be the idler pulley.
Reply With Quote
  #4  
Old March 5th, 2007, 00:16
Midnight Krawler Midnight Krawler is offline
NAXJA Forum User
 
Join Date: Jun 2005
Location: Fremont California S.F Bay area
Posts: 225
Re: Weird Squealing Noise...

A dry distributor bearing can cause a squeal.
Reply With Quote
  #5  
Old March 5th, 2007, 01:47
EMSJEEP's Avatar
EMSJEEP EMSJEEP is offline
NAXJA Forum User
 
Join Date: Jul 2006
Location: Long Island
Posts: 794
Re: Weird Squealing Noise...

http://www.naxja.org/forum/showthread.php?t=92215

If the belt is loose enough it will do it dry. You need a tension gauge and the tools to tighten the idler pully...a new belt if its worn wouldn't hurt either.
Reply With Quote
  #6  
Old March 5th, 2007, 11:31
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Re: Weird Squealing Noise...

Hi,

Thx for the replies... keep 'em coming.

a Dry Distributor Bearing hmmmm... the Dist is a reman and was put in at same time the engine swapped. Can I lube this bearing by taking the Dist Cap off and rotor?

By the way, could this squeal cause any damage to the engine when I drive?

Thx Again. Phil
Reply With Quote
  #7  
Old April 22nd, 2007, 01:18
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Re: Weird Squealing Noise...

Quote:
Originally Posted by EMSJEEP
http://www.naxja.org/forum/showthread.php?t=92215

If the belt is loose enough it will do it dry. You need a tension gauge and the tools to tighten the idler pully...a new belt if its worn wouldn't hurt either.

Ok, I finally got around to find some time to work on the squealing prob. I tightened the belt so I only have a 1/2 inch up/down of deflection and I sprayed the belt with belt dressing spray.

Fired it up and no dice same squealing prob. At first I thought it was the A/C Compressor since the sound seems to be coming from around there but when I turn on the A/C it blows cold (so I guess the A/C's ok?).

Next to the A/C is the Idler Pulley and Below is the Alternator. Well, the Alternator is producing current (judging by the guage 14volts).

**How do I go about checking the Idler Pulley and How do I tighten it? How do I remove it (if it's bad)? Do I need any special tools?

**Btw- The noise starts as a low pitched squeal and gets louder until I rev the engine then it goes away. At times it sounds like a low pitched whistle.

**Q - What Idler Pulleys from other Year 4.0L's (mine's an 88) will fit my Engine if I can't get one for an 1988? Any decent online sources for this part (part #?)?

**Q - Will it damage the engine if I drive it to a Mechanic?

**Q - What should a job like this cost?

Thx.
Reply With Quote
  #8  
Old April 22nd, 2007, 08:03
sjx40250's Avatar
sjx40250 sjx40250 is offline
NAXJA Forum User
 
Join Date: Jan 2004
Location: Alexandria VA
Posts: 1,176
Re: Weird Squealing Noise...

At the most, Idler pulleys are $30. I have replaced 2, one on my 90.
The way I tested mine was by using a sanding belt cut to the right width. I then used the chuck of my 3/8" drill to drive the belt that was over the pulley. (gotta get the belt loose first!). As it turns out, My alternator was the root of the problem with the rear bearing making the noise.
In either case, you can drive it around. I drove my 90 with the idler pulley bearing gone for several months. It just gets loose and goes into a harmonic vibrations. That is why it only shows up at certains speeds.
If you can tighten the belt, you can change the idler. Don't waste the money on a mechanic for such a simple effort. One bolt in the middle of the pulley and it is off.
Reply With Quote
  #9  
Old April 22nd, 2007, 09:40
Jess Jess is offline
NAXJA Forum User
 
Join Date: Mar 2006
Location: Tennessee
Posts: 2,393
Re: Weird Squealing Noise...

don't just guess and throw money at it.

Use a piece of heater hose and put one end to your ear and probe with the other end. Where the squeal is coming from should be evident using this method. Chances are it is the bearings in either the waterpump or the power steering pump that are going bad. The alternator and the AC may or may not make this noise when going bad. If it is the idle pulley you should be able to pull on it and get some flex out of it. If it is the harmonic balancer it will we wearing on the timing cover and the belt will want to move off the other pulleys.

Learn to diagnose the problem-throwing money at a problem you will only learn how much patience and money you have...until you get lucky or broke!
Reply With Quote
  #10  
Old April 22nd, 2007, 19:42
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Re: Weird Squealing Noise...

Thx for all the suggestions... I need some more please.

Ok, I tried the length of heater hose to locate the source of noise. Turns out the Idler Pulley was the culprit!

It was too late to get/order the part from AutoBarn so in the interim I decided to loosen the belt and try to remove the bolt holding the Idler Pulley.

Man, it's seized shut! I tried Liquid Wrench and some other brand of Penetrating Oil, then kept tapping (repeated this many times too) the seized bolt. No Dice, wouldn't budge. On top of that I'm afraid to break the bolt.

**How do you guys get a seized bolt loose? Would heating the bolt from a propane torch help?

After about two hours of trying I gave up. I then fired up the engine and it seems the Penetrating Oil made the Squealing Noise go away! But for how long is the question. Also, since I loosened the belt I checked for any play or wobble in the Pulley; seems nice and tight, spins freely w/o squealing too.

**Are you supposed to lube these pulleys periodically or are their bearings sealed and have grease internally?

**Worst case... what happens if I break the bolt?

**Also, what if I leave the old pulley and just lube it now and then would it then have enough lube in it to last a while and/or would it squeal again due to friction thus causing heat and that's bad? Hope I'm making sense.

Thx.
Reply With Quote
  #11  
Old April 22nd, 2007, 20:33
Jess Jess is offline
NAXJA Forum User
 
Join Date: Mar 2006
Location: Tennessee
Posts: 2,393
Re: Weird Squealing Noise...

As I recall that bolt is pretty tight, but it is into a bracket and not the head--so if it breaks you go to the salvage yard and get a new bracket for a few bucks. If the noise was definately coming from the idler pulley (and not the alternator right below it) you should replace it. The last one I got was about $15. Use a breaker bar and remove the pulley (15 mm-I think).

I make a point of not lubing anything around the belt, because that causes slipping of the belt.
Reply With Quote
  #12  
Old April 23rd, 2007, 00:44
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Re: Weird Squealing Noise...

Quote:
Originally Posted by Jess
As I recall that bolt is pretty tight, but it is into a bracket and not the head--so if it breaks you go to the salvage yard and get a new bracket for a few bucks. If the noise was definately coming from the idler pulley (and not the alternator right below it) you should replace it. The last one I got was about $15. Use a breaker bar and remove the pulley (15 mm-I think).

I make a point of not lubing anything around the belt, because that causes slipping of the belt.
So if the bolt breaks I can get another bracket cheap at a junkyard...

1. What about the A/C and the Alternator (donno if it's connected to the same bracket), are they difficult for the novice to remove/replace/recharge and do they need special tools and skills to do so?

2. Would just lubing the idler pulley suffice if I can't get it off since the bolt is seized?

3. Also, b4 I lubed the pulley I noticed there were chunks of rubber stuck to the smooth pulley surface probably that peeled off from the belt. What's causing this (belt too tight or other causes)?

Thx.
Reply With Quote
  #13  
Old April 23rd, 2007, 19:37
Jess Jess is offline
NAXJA Forum User
 
Join Date: Mar 2006
Location: Tennessee
Posts: 2,393
Re: Weird Squealing Noise...

1. easy to remove/replace--only bolts and nuts
2. use a big breaker bar and bust the bolt loose (try to loosen and then tighten and then loosen and this should break any rust off). The bracket is aluminum so it shouldn't be rusted in
3. old belts break down from the heat, just get a new belt
Reply With Quote
  #14  
Old April 23rd, 2007, 23:24
DIGITRUCK DIGITRUCK is offline
NAXJA Forum User
 
Join Date: Dec 2005
Location: NY
Posts: 124
Question Re: Weird Squealing Noise...

Quote:
Originally Posted by Jess
1. easy to remove/replace--only bolts and nuts
2. use a big breaker bar and bust the bolt loose (try to loosen and then tighten and then loosen and this should break any rust off). The bracket is aluminum so it shouldn't be rusted in
3. old belts break down from the heat, just get a new belt

1. What about the A/C? Does it need any special tools to drain the freon and then recharge after?

I was gonna try Heat today from a hand held propane torch but gave it one last shot of elbow grease and CRACK... IT BROKE FREE, YIPPEE!!!

I guess the Penatrating Oil worked it's way in overnight somehow. Phew.

Got parts from Autobarn made by Dayco. Serp. Belt and Idler Pulley. Went in just fine.

1a. I put some ANTI-SEIZE COMPOUND on the threads of the Bolt so next time it won't be so difficult to remove. Good idea?

2. Oddly enough there is some play (wobble) in the new Pulley (the old one didn't have any play only squealed). Is this normal? It doesn't seem to affect it and there's no squealing sound anymore.

Thx.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
squealing noise from front of jeep Boulder_jeeps OEM Tech Discussion 3 August 8th, 2006 21:21
Squealing noise Cherokeekid88 OEM Tech Discussion 1 July 16th, 2006 22:11
Weird noise falcon556 OEM Tech Discussion 7 April 8th, 2006 18:06
Squealing Noise AJ-MJ OEM Tech Discussion 2 March 7th, 2004 09:31
Help..weird noise at 55-65 mph!! sticksb OEM Tech Discussion 1 August 7th, 2003 23:39


All times are GMT -7. The time now is 05:59.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
NAXJA and NAXJA logo's Copyright NAXJA. All content/images Copyright NAXJA 1999-2014