Re: A/C compressor squeel

[Chas Henderson #28127]

Jack and Lyndon, I did put 134a in it. I replaced the dryer and expantion valve five years ago, but I changed over to 134a last week. The belt's tention seems correct and where in my 71 service manual would I find the specs? I looked in there to try and find out how to rebuild the compressor, but found nothing other than how to remove / replace it.

Chasman

[Jack H.]

Re: A/C compressor squeel

(1) Belt Tension: Refer to Sect 6-5 of Chassis Service Manual in conjunction with Engine Tune Up Table in Specifications section. Correct tension of AC belt is 95 +/- 5 lbs for a used belt with 65 lb minimum.

(2) AC Clutch Air Gap: This used to be covered in the CSM and Corvette Shop Manuals but the A6 Compressor technical details moved to the Chassis Overhaul Manual by 1971. Read Sect 1 of the COM for details and find the air gap dimensions for the A6 clutch face spec'd at 0.022 and 0.57 inches....

[Dick W.]

Re: A/C compressor squeel

If you did not change the dryer when you changed over to R-134a you could be setting yourself up for trouble. What oil did you use? Have you installed a set of test guages to see what your actual pressures are? It could be that the high side pressure is so high that it overloading the compressor drive. The latter would be my guess as to what is causing the belt to squeal since it did not start until you changed over. R-134a will run slightly higher head pressures than R-12, but not to the extremes. I changed over several 70-72 cars to R-134a with no problems. Used PAG oil and a new dryer.

[lyndon sharpton]

Re: A/C compressor squeel

Dick,

did you like the 134a? did the old cars feel as cool?

[Dick W.]

[lyndon sharpton]

Re: A/C compressor squeel

let me know Dick how that project truns out.