A/C-related Squeal (Belt?)

[KPW]

Hi All -



I've noticed that when I first turn the A/C on, I get a squealing noise when I start to drive. Usually only lasts for the first 50ft or so. Most obvious in 1st or Reverse as I let the clutch out.



A/C seems to be functioning well (compressor seems to rotate OK by hand)...belt is new in the last two years (Continental Poly-V).



Has anyone run into this before? My feeling is that it's probably more belt than A/C, but strange that it only squeals when the A/C kicks on and at low RPM.

[Ccmano]

Most likely the belt. Make sure you have the right belt. Not everyone has the correct spec on the belt.

http://www.zr1.net/forum/showthread.php?t=28665&highlight=Belt

H
:cheers:

[KPW]

Aha. I think I remember having the 80.5 at some point. I'll double-check what's on the car and what my spare is. Thanks for the tip.:cheers:

[Dynomite]

Aha. I think I remember having the 80.5 at some point. I'll double-check what's on the car and what my spare is. Thanks for the tip.:cheers:

My Billet Aluminum Alternator Pulleys are just a tad larger in diameter than the stock alternator pulley.
The belt lengths I use now ARE 80.5 inch outside length....:)

I install the belt by slipping the back side of the belt onto the smooth Billet Aluminum Water Pump Pulley last.

https://cimg0.ibsrv.net/gimg/www.corvetteforum.com-vbulletin/400x500-1/80-d8a219b2_f604_4653_9c28_360157f1027b_1__92ce0c47b0 9178ed8afc9a7a24145b03ddde9fdd.jpghttps://cimg2.ibsrv.net/gimg/www.corvetteforum.com-vbulletin/400x500/80-992f36c2_d357_4f2c_9918_b3ac31b4ab6b_1__70901d2d6f 7aaeb69783cf2f3178d4df14e6932f.jpg

[onetinsoldier]

You may want to check the ac clutch bearing . I had one go bad and press against the snap ring , it cut off the snout on the compressor and trying to find a replacement part for a zr1 is about impossible !

[Paul Workman]

You may want to check the ac clutch bearing . I had one go bad and press against the snap ring , it cut off the snout on the compressor and trying to find a replacement part for a zr1 is about impossible !

DITTO (there, Hans, you see it again!)

I wuz gonna mention the clutch and or the bearing.

NOTE: If you first spritz a little water or windex on the belt with the engine running, and then turn on the AC, if there is no squealing yet the AC compressor still turns normally, chances are it is the belt and/or the belt tensioner. If the belt ribs display cracking - for sure the belt is in need of replacement - regardless of anything else that might need attention...

A Mechanic's stethoscope is another way to find out if it is a bearing or not. But, first pull the diaphragm with the metal probe from the rubber hose. Use the open end of the rubber hose to probe for the squealing - works much better than the metal probe in some cases (a trick I leaned from Marc Haibeck).