A/C Issues
Thread Starter
Racer
Joined: Jul 2008
Posts: 446
Likes: 1
From: Cary NC
A/C Issues
I am trying to diagnose my A/C in a '79. Is there a guide for this? The air blows but the compressor never starts. Heat works fine. Could it be just the compressor? I have read something about jump starting the compressor, any ideas? Also if I want to convert to 134 (is it difficult?) would it be better to buy a certain type of compressor?
Thanks,
Michal
Thanks,
Michal
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
You probably lost the freon charge due to a leak. There is a low pressure switch in the system that disables the compressor if the pressure is to low. The 79' GM Service manual has lots of info on trouble shooting the system.
Gary
Gary
.
Burning Brakes
Joined: Jun 2008
Posts: 1,086
Likes: 1
From: Michigan
I agree with Duke. Loss of pressure trips the switch to prevent damage to the compressor and the service manual has lots of fault trees and diagnostics.
Converting to R134a is easy and many places sell conversion kits including your local auto store. The trick is to study your system before you start messing around with it.
It is under a lot of pressure.
You need a few special tools like gauges and a vacuum pump. The gauges can be purchased with a refill kit, and the vacuum pump can be rented for free from Autozone.
Legally, you need to have a licensed person or shop remove and dispose of the old R12.
The retro kits come with what you need including new R134a compatable o-rings.
Don't leave the system open or discharged for any longer than you have to. Plug hoses when you remove fasteners.
Replace critical components.
Flush the condenser and evaporator with A/C flush.
Don't forget to add PAG oil to the compressor and system.
Here is some starter reading:
http://www.corvetteforum.net/c3/zwed...c/retrofit.htm
Converting to R134a is easy and many places sell conversion kits including your local auto store. The trick is to study your system before you start messing around with it.
It is under a lot of pressure.
You need a few special tools like gauges and a vacuum pump. The gauges can be purchased with a refill kit, and the vacuum pump can be rented for free from Autozone.
Legally, you need to have a licensed person or shop remove and dispose of the old R12.
The retro kits come with what you need including new R134a compatable o-rings.
Don't leave the system open or discharged for any longer than you have to. Plug hoses when you remove fasteners.
Replace critical components.
Flush the condenser and evaporator with A/C flush.
Don't forget to add PAG oil to the compressor and system.
Here is some starter reading:
http://www.corvetteforum.net/c3/zwed...c/retrofit.htm
Last edited by 08vycpe; May 10, 2009 at 04:53 PM.
