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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Engine Short Squeal At Startup

  • Thread starter Thread starter boostfrk
  • Start date Start date Oct 5, 2016

boostfrk

10 Year Member
Aug 30, 2011
712
69
59
Colorado
Oct 5, 2016
#1
  • Oct 5, 2016
  • #1
I have an annoying short squeal upon initial/cold startup. It only lasts a second, just right when the motor catches and actually starts is when it happens. But it's annoying. It doesn't do it if the car is warmed up and has been running.

I've searched and seen that this can often be the bearings failing in the accessories (power steering pump, alternator, etc).

The PS pump, alternator and water pump are all new within the past year or two and only have a couple thousand miles on them. I also replaced the smog pump with another one...still does it. I have replaced the idler pulley as well.

I've tried different size belts too (stock sized 905, a 900 and an 895) and I get the squeal with each one.

About the only thing I haven't replaced yet is the tensioner itself. The pointer still shows that the tension is within the acceptable "range". Is there something about a slightly failing/old tensioner that will allow the belt to squeal at cold startup? Any other ideas?
 

Moosee1955

Active Member
Sep 30, 2016
267
55
38
Oct 5, 2016
#2
  • Oct 5, 2016
  • #2
Best way to diagnose any bearing sound, is to remove belt when cold. Spin each pulley, tensioner, alternator, etc. when you get to the failing one, you usually get one that sounds like a worn old skate wheel. I would have guessed belt, but you've replaced 3 times. When you pull serpentine belt, get in there on pulleys with a brush. Clean grooves real good. Theirs a gasket sealer/ belt dressing called gaskacinch. Available at motorcycle shops or online. Works great as a gasket sealer, but in your case on fan belts. As always keep us posted what you find.


Sent from my iPhone using Tapatalk
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Oct 5, 2016
#3
  • Oct 5, 2016
  • #3
before you start swapping out parts, check the alignment of your pulleys.. Squeals are either a belt or pulley alignment problem. If you have a long straight edge, line it up with the crank pulley and then move the other end to each of the other pulleys.. If you have put on a new PS pulley or pump chances are the PS pulley may not be aligned, causing the squeal.

Then with the belt on, start the car. Spray some water on the belt by each pulley That can also help to isolate which pulley is misaligned. A bad tensioner can also do what you describe. Can you see on the face of it if the arrow it still within range? Yours is 20+ years old and the spring does wear out. HAve someone start the car and see if you notice the tensioner jump
 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Oct 5, 2016
#4
  • Oct 5, 2016
  • #4
I had this. Had a PS leak that was misting the belt with fluid. Made noise on start up and went away after a moment.
 

boostfrk

10 Year Member
Aug 30, 2011
712
69
59
Colorado
Oct 18, 2016
#5
  • Oct 18, 2016
  • #5
Sorry for the screwy original post...I've been having some horrible times getting onto StangNet for several weeks.

I took the belt off, turned all the pulleys by hand and no skate wheel type sound.

I then cleaned all the pulleys real well with a brush and water, as well as cleaning the belt, and then let everything dry overnight.

No change at all.

So I don't know what it was, but I ended up selling the car yesterday (not because of the belt) so I guess I'm not worrying about this anymore.
 
Last edited: Oct 19, 2016
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