A year ago I changed out my 84 to 134a. New Compressor, new accumlalor, new filter, new oil, etc. However I can rarely use the AC due to the horrible compressor squeal I've got. If it stops squealing ,it pumps out nice cold air, but everytime the compressor cycles.... giant squeal again. The belt is super tight, and I dont think I could get it any tigher if I wanted to , I am at the end of the travel on the bracket. Any secret to getting this to work without squealing?
I came across one post that said 134A worked at higher pressure, and therefore the compressor would be harder to turn. Perhaps a V-belt can't turn it, and it really needs a serpantine belt ??? I know other guys have converted to 134a, presumablly without this issue. Any secret....or is my 'new' compressor bad ???
Use a Gate's belt. Stock size. Tighten until you can twist the belt by hand in the middle of the run 90* but no more. It sounds like your belt is too tight.
Try closing up the air gap on the compressor clutch.
Larry, thanks for the reply. Can you explain why you think it would be the air gap? Since this is a new compressor, I wouldn't expect there to be any wear which wou ld lead to the need for an adjustment. Also, the squeal comes when the compressor is turned on/ engaging. My understanding of when an air gap adjustment is needed is when the compressor will NOT engage or disengages prematurely.
Sometiems a belt can get glazed from slipping even if you tighten or over tighten it it may still squeal. I too recommend a new belt. Gates or Goodyear Gatorback brand. You can also lightly sand the "glaze" off the old one. Make sure you have the correct belt and not one too big, If there is not enough room to tighten before the end of the slot try a smaller belt.
[This message has been edited by 2.5 (edited 07-22-2014).]
All this talk about the belt, and none about the AC. Have you measured both the low and high pressure while it is in operation? Are both in spec? If the low pressure is OK, but the high pressure is too high, that points to a clogged orifice tube. Crud in the system from a previous failed compressor can cause that. As for the belt, try a little spray on belt dressing. It's only a temp fix, but it may allow you to take those pressure readings.
Thanks all, I'll try a new belt. Can anyone confirm that NAPA sells Gates belts under the Napa brand? The description looks the same, but can't find anything branded as a Gates belt round me.
As for the pressure, I haven't checked it, but can say that when we evacuated the R12 for the change to 134a, the orifice was clean, and a new orifice was installed anyways. I'll see if I can find someone to check the pressure.
