| [GMCnet] A/C Question [message #366307] |
Tue, 24 August 2021 10:02  |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma:
|
Senior Member |
|
|
I need the opinions of those more HVAC knowledgeable than I am: Since the
pandemic kept us off the road for over a year, I find that the A/C no
longer works (equipped with a Sanden compressor and Duracool, it had
operated without attention for the previous 5 years or so).
A couple of days ago, I vacuumed the system down to near 30 in.HG. and left
it sitting until today, when it was still at almost that level. Then I
moved the vacuum hose to a fresh can of Duracool and opened the valves.
The low-side and high-side gauges both immediately indicated ~95 psi. Then
I started the engine and engaged the compressor. Neither gauge's needle
even flickered! Repeated compressor clutch cycles yielded the same
results: Click-clack of the compressor clutch and obvious rotation of the
compressor shaft -- yet NO needle movements.
I took a brass hammer and rather strenuously rapped the compressor (on
"hard parts") hoping I might shake something loose inside -- STILL no
needle movement with clutch cycling.
My diagnosis is that I have one of 3 problems in the Sanden compressor:
1. A sheared shaft; 2. A valve stuck open; or, 3. a busted piston -- in
that order of probablility. Does anyone, hopefully, have another/better
idea? Maybe even one that won't require compressor replacement?
It's looking less and less like I'll really need A/C in the GMC this year,
but I'd still like to get it working before I get still older and less able
to tinker, so Y'All's opinions will be greatly appreciated.
Ken H.
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
