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Belt Squeal with Underdrive Pulleys

  • Thread starter Thread starter Slo5Oh89
  • Start date Start date Mar 27, 2010

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Mar 27, 2010
#1
  • Mar 27, 2010
  • #1
I just installed a set of underdrive pulleys and now I have a belt squealing. It did seem to go away but I tried it with the AC on and it started doing it again when i would rev it? Is it just from the gloss on the new pulleys or any ideas?
 
P

phutch11

Member
Nov 14, 2005
328
2
18
Mar 27, 2010
#2
  • Mar 27, 2010
  • #2
When I installed mine, I put the alternator pulley wrong either it wa on backwards on there was a spacer I did not install correctly, can't remember.

This offset the pulley by about an eighth of an inch. It squealed like a stick pig. I wasted months replacing belts and tensioners.

Take a straight edge and make sure all your pulleys are lined up exactly.

Good luck....
 

SpartaPerformance

10 Year Member
Nov 5, 2006
2,517
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89
Long Island NY
Mar 27, 2010
#3
  • Mar 27, 2010
  • #3
Squealed like a stick pig?
 

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Mar 27, 2010
#4
  • Mar 27, 2010
  • #4
Well acutally I did not put on the Alt Pulley becuase I do not have a impact gun to swap it out. I have a nice socket and ratchet set. Would the alignment be off becuase I left the stock Alt Pulley On. And can it be changed with a ratchet? And then maybe torqued with a torque wrench and if yes how much? Any ideas guys? Anyone change the alt pulley with out a impact gun?
 
P

phutch11

Member
Nov 14, 2005
328
2
18
Mar 27, 2010
#5
  • Mar 27, 2010
  • #5
Damn blackberry with the double letter keys screwing me again!!!!
 

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Mar 28, 2010
#6
  • Mar 28, 2010
  • #6
Ok. Anyone else have a helpful reply!
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,252
17,937
224
Massachusetts
Mar 28, 2010
#7
  • Mar 28, 2010
  • #7
Take a bar of soap, and VERY CAREFULLY, apply it to the ribbed side of the belt. If it quiets down, get a new belt.

But BE CAREFUL when doing this. Don't want to get a finger caught.
 
9

93luv

Member
Feb 24, 2010
35
0
7
san antonio
Mar 28, 2010
#8
  • Mar 28, 2010
  • #8
#1 cause of belt squeal is simply a loose belt...
make sure belt is tight first..about 3/8-1/2 inch movement max when pressed w/fingers hard.

as for the pulleys, with the belt on tighten the hell out of em no torque wrench needed...just put your weight on it-

if you put pulleys on with the belt off; then put the belt on and didnt tighten them down some more, they may not be tight enough...which would explain the squeal at high rpms and with extra load like a/c clutch engaging
 

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Mar 29, 2010
#9
  • Mar 29, 2010
  • #9
I will check the belt being tight enough.

I will also double check all the bolts on the Water Pump and Crank Pulleys.

I only get a squeal with the AC at low RPM in the 1-2500 area. When the AC is on. It did have a squeal when I first turned it on but it went away thought maybe it was the slick coating on the pulleys.

Also I did not put the Alt Pulley on would that matter at all? I don't have a impact to do so.
 

Gearbanger 101

Straight Outta Locash
20+ Year Stangneter
Aug 10, 2002
9,457
1,377
234
Ontario, Canada
Mar 29, 2010
#10
  • Mar 29, 2010
  • #10
Step 1 Remove belt and inspect for visual wear, cracks, rot, etc
Step 2 Inspect tensioner for weak spring, or damage
Step 3 Assuming belt and tensioner pass inspection in steps 1 & 2, clean belt in bucket of "scalding" hot water with a stiff bristled brush and dish soap.
Step 4 Spray all pulleys with Brake Cleaner, wipe off excess.
Step 5 Re install belt and enjoy squeak free performance.
 

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Mar 29, 2010
#11
  • Mar 29, 2010
  • #11
Ok, I will try that for sure with the brake cleaner, the belt is only a couple months old. But it is the stock tensioner.
 

Slo5Oh89

Member
Oct 8, 2009
226
3
19
Washington, IL
Mar 30, 2010
#12
  • Mar 30, 2010
  • #12
I cleaned the pulleys got a lot of gunk off the air pump pulley but the rest looked fine. Still have a low RPM squeal from the AC/Defroster when its on.

Anyone think its becuase the belt is to long becuase I did not install the ALT Underdrive pulley? Or tensoner just cant handle it now with the extra load? Or the AC/Defroster clutch is going out. But I never had a single noise out of it till I put the pullies on and the belt is newer few months old.
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Mar 30, 2010
#13
  • Mar 30, 2010
  • #13
Is the tensioner out of travel? If it is get a shorter belt..
 
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