belt squeal on startup

[shotimev6]

when i start up my 91 plus one of the belts squeal. im not exactly sure which one it is and it happens mostly on cold startups. it goes away in about 5 seconds. anyone else have this problem?

 

[dkal]

shotimev6:
when i start up my 91 plus one of the belts squeal. im not exactly sure which one it is and it happens mostly on cold startups. it goes away in about 5 seconds. anyone else have this problem?

On my 95MTX I had my serpentine belts replaced when I had the timing belt changed. The dealer did the work and when I picked the car up I noticed a belt squeal when I started the car. I didn't know which belt was squealing or whether they both were. I did know when I started the car up and switched the A/C on, the belt squealed and continued to squeal until I turned it off.
I took it back to the mechanic and he tightened the belt, since the car was already warm the belt didn't squeal when I first started the A/C, it did when I was driving about 60-65mph.
I knew the belt wasn't tight enough because the belt squealed when the car was cold.
I guess you have to determine whether the belts are in good condition, if they are have them tightened.
Have to determine which belt was was loose.

Good luck.
Dkal

 

[SolidState]

dkal, that belt squeal might be a sign that your AC clutch is going....my parents aerostar has the same problem.

 

[cRaZySHO.]

Check the tightness first. My 95 MTX did the samething this past winter. And I had just changed both belts, and I didn't tighten the power steering belt tight enough(smaller 4 rib belt, towards rear.)

 

[dkal]

dkal:

shotimev6:
when i start up my 91 plus one of the belts squeal. im not exactly sure which one it is and it happens mostly on cold startups. it goes away in about 5 seconds. anyone else have this problem?

On my 95MTX I had my serpentine belts replaced when I had the timing belt changed. The dealer did the work and when I picked the car up I noticed a belt squeal when I started the car. I didn't know which belt was squealing or whether they both were. I did know when I started the car up and switched the A/C on, the belt squealed and continued to squeal until I turned it off.
I took it back to the mechanic and he tightened the belt, since the car was already warm the belt didn't squeal when I first started the A/C, it did when I was driving about 60-65mph.
I knew the belt wasn't tight enough because the belt squealed when the car was cold on initial startup.
I guess you have to determine whether the belts are in good condition, if they are have them tightened.
Have to determine which belt is loose.

Good luck.
Dkal

 

[sdpatt]

Your belt simply needs to be tightened enough to prevent the slippage that is causing the squealing. Listen to the compressor to ensure it sounds healthy, but chances are it is just a loose belt. Relax.

To tighten the belt, First loosen the 14mm nut on the tensioner pulley, then turn the Allen screw clockwise to apply more tension to the belt. Only enough to prevent the compressor engagement from causing a chirp when the engine is running around 3,000 rpm. Retorque the 14mm nut to 25 lb-ft.

<small>[ September 13, 2002, 09:33 PM: Message edited by: sdpatt ]</small>

 

[shotimev6]

my squeal has nothing to do with a/c. it isnt even on. its when i start the car for about the first five seconds. if the belt tension was incorrect wouldnt it do it all the time?

 

[dkal]

Originally posted by shotimev6:
<strong>my squeal has nothing to do with a/c. it isnt even on. its when i start the car for about the first five seconds. if the belt tension was incorrect wouldnt it do it all the time?</strong>[/QUOTE

Are the belt or belts wore? Did you inspect them for cracks, frays or broken cords?

3.2L SHO engines have automatic belt tensioners, indicator mark on the tensioner indicates belt wear. No adjustment necessary.

On 3.0 SHO engines, there are two belts which are adjusted by loosening the idler/pulley nuts and turning the adjuster screws CW or CCW, and torque the idler/pulley nuts to spec.
If the latter applies to you, I thought by switching the A/C on would help isolate which belt was loose, otherwise you would be adjusting a belt which wasn't loose, eventually you would eliminate the squeal, but you may overtighten one of them.

An incorrect idler/pulley adjustment would not result in a belt squeal all the time. The belt may not slip at 900 rpm's, however it may at 3000 rpm's when driving. Depends on how loose it is.

Dkal

 

[sdpatt]

shotimev6:
my squeal has nothing to do with a/c. it isnt even on. its when i start the car for about the first five seconds. if the belt tension was incorrect wouldnt it do it all the time?

The alternator and A/C belt is a six rib belt because it has the greatest inertial loads to deal with and loads that vary with electrical demands and A/C system settings. The alternator has a significant mass that takes energy to spin up to speed. If the bet is loose, you will hear the squealing due to slippage as the alternator spins up. The A/C compressor is not a factor at startup, but is the most challenging to the belt at higher engine speeds (3,000 rpm) when the clutch engages. That is the minimum tightness to prevent chirping that is required.

 

[rendyx]

Did you spill anything in the engine bay recently? Sometimes after I wash my SHO or degrease under the hood, I'll get some squeeling for a day or two.

 

[shotimev6]

it only squeals at low rpm's at startup. if i rev the engine it goes away faster.

 

[sdpatt]

You might want to check your idler pulleys and accessories for free-turning shafts.