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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

horrible belt squeaking...

  • Thread starter Thread starter chaos254
  • Start date Start date Dec 26, 2007

chaos254

Founding Member
Jul 27, 2002
467
3
29
NJ
Dec 26, 2007
#1
  • Dec 26, 2007
  • #1
My belt has been squeaking for awhile now but recently it has gotten a lot worse. I changed the belt before my trip cross country and didn't help. I run a 895k6 belt since I don't have smog. Sometimes it will go away after driving around for awhile but the sound is HORRIBLE on startup and gets worse with higher rpms.

I tried that belt conditioner crap, which is actually crap because it just made the belt squeak even worse

I've done a search and basically it hasn't helped because obviously there is a bunch of things that could cause it. Belt too tight, too lose, tensioner, idler, smog, etc.

I never had a problem running the shorter belt until recently so I don't believe the size is wrong. I also checked my pullies to see if anyone were loose. The idler seemed to move a tiny bit side to side.

Its just hard to diagnose any car issues when I'm not supposed to work on my car in my apartment complex. So if its the tensioner I will probably have to bring it to a shop.

Any suggestions would be great.


EDIT: forgot to mention I have ASP underdrive pullies and the belt is from advanced auto
 

milewsky80

Member
Nov 25, 2004
69
0
6
Weirton, WV
Dec 26, 2007
#2
  • Dec 26, 2007
  • #2
Mine always squeaked after deleting the smog until I tried a 90" gatorback, it hasn't squeaked in 3k miles
 

Pokageek

Active Member
Jun 10, 2005
2,767
0
46
MA, USA
Dec 26, 2007
#3
  • Dec 26, 2007
  • #3
Been where yo uare and VERY FRUSTRATING!! I found my FRPP undr drv crank pulley was sticking OUT too far with my new balancer of the 414. That made it squeak like a mofo! Make sure all pulleys are properly tightened and IN LINE, then be sure the belt is within the "safe" marks on the tensioner. You'll know you have the right size if it is between the marks..make sense?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Dec 26, 2007
#4
  • Dec 26, 2007
  • #4
Keith hit upon something very important. Pulley alignment.

In my experience, a tell is that if belt dressing makes a squeal worse, it's the pulley alignment. Normally the belt is riding improperly over the pulley (the one with the incorrect endplay/longitudinal displacement). It just kinda 'slips' over the ribs, making some noise. When you make the belt sticky, it starts wailing because you just increased mew so much.

JMHO.
Good luck.
 

chaos254

Founding Member
Jul 27, 2002
467
3
29
NJ
Dec 27, 2007
#5
  • Dec 27, 2007
  • #5
Pokageek said:
Been where yo uare and VERY FRUSTRATING!! I found my FRPP undr drv crank pulley was sticking OUT too far with my new balancer of the 414. That made it squeak like a mofo! Make sure all pulleys are properly tightened and IN LINE, then be sure the belt is within the "safe" marks on the tensioner. You'll know you have the right size if it is between the marks..make sense?
Click to expand...

what do you mean safe marks on the tensioner? Do you have a pic of this? I looked and saw 2 lines but wasn't sure if they were in the right place or not. Also saw some kind of pointer but they were no where near the lines that I saw...
 
D

Dancingbear

New Member
Oct 3, 2008
1
0
0
Mar 4, 2009
#6
  • Mar 4, 2009
  • #6
I am having the same awful squeal problem on my '93 5.0 HO engine (in a 70 shelby convertible). The noise quiets down after 5-10 minutes, but it is awful otherwise.
A long builder's bubble-level (straight-edge) shows that everything is aligned in the vertical plane.
The belt conditioner does not help at all, but vaseline on the pulleys helped a little... then it came back.
The barsoap idea is interesting, but we would welcome other ideas.

Thanks
 

toyman

10 Year Member
Jul 19, 2007
1,944
54
79
Vernon BC
Mar 4, 2009
#7
  • Mar 4, 2009
  • #7
[
I never had a problem running the shorter belt until recently so I don't believe the size is wrong. I also checked my pullies to see if anyone were loose. The idler seemed to move a tiny bit side to side.

Any suggestions would be great.
Click to expand...

If the idler moves side to side just replace it (There should be no lateral movement). Worn bearings here and in the tensioner pulley will squeal.

Richard
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Mar 5, 2009
#8
  • Mar 5, 2009
  • #8
Dancingbear said:
I am having the same awful squeal problem on my '93 5.0 HO engine (in a 70 shelby convertible). The noise quiets down after 5-10 minutes, but it is awful otherwise.
A long builder's bubble-level (straight-edge) shows that everything is aligned in the vertical plane.
The belt conditioner does not help at all, but vaseline on the pulleys helped a little... then it came back.
The barsoap idea is interesting, but we would welcome other ideas.

Thanks
Click to expand...

Did you testing also check that none of the pulleys are cockeyed (like one accessory sits crooked in its mount, so the ribs in the belt try to 'jump' as they ride)? I figure you did but if only one portion of the pulley was checked for the vertical-plane test

Have you tried a new belt? Some belts squeal more than other brands or styles (there are some crap belts out there these days). Also, once a belt is glazed or has had dressing applied, it can be permanently hosed.

I'd consider a new one and toss the squealer in the trunk for a spare.

Good luck. And feel free to throw up some pics of your ride for us.
 

99FiveOh

15 Year Member
May 20, 2006
2,051
20
99
J-Ville, FL
Mar 5, 2009
#9
  • Mar 5, 2009
  • #9
sometimes reversing the belt has helped me. I noticed the belts that have "teeth" like grooves in them don't squeal at all!
 
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