79' A/C conversion questions
Thread Starter
Instructor
Joined: May 2011
Posts: 135
Likes: 0
From: Horicon Wisconsin
79' A/C conversion questions
So when I pulled the motor out, my system had a small amount of pressure in it but it didnt work. So my questions are.
Is there a way to test the compressor with it out of the car to make sure it works?
What do I all need to convert over to 134?
Any other tips are most welcomed!!
Thanks
Is there a way to test the compressor with it out of the car to make sure it works?
What do I all need to convert over to 134?
Any other tips are most welcomed!!
Thanks
Melting Slicks
Joined: Oct 2006
Posts: 2,417
Likes: 336
From: Texas
when i did my 79 L82's ac i replaced about everything but the condensor core and evaporator core.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
Burning Brakes
Joined: Sep 2006
Posts: 1,071
Likes: 86
From: Rotonda FL
With two exceptions. 1) I have not had good luck with R4 compressors running 134a. They just do not seem to last. I suggest converting to a Sanden 508. These are smaller and have less drag than the R4 and seem to be very durable. The cost of a 508 and mounts will be made up with one replacement R4. 2) You will get better performance (colder air) if you switch to a modern multipath condenser. You can purchase one plus mounts from Vintage Air, or use your original mounts with adapters (see below) if you need more info, PM me.
http://i1123.photobucket.com/albums/...install001.jpg
http://i1123.photobucket.com/albums/...install002.jpg
Le Mans Master
Joined: Sep 2004
Posts: 5,116
Likes: 5
From: Livonia MI
For the original question. If you still had some system pressure, most is probably still ok, except likely a leaking compressor shaft seal. The system low pressure switch was probably preventing the compressor from coming on. I'd just get the shaft seal replaced, maybe a new dessicant, evacuate the system and recharge with R-12. Not a bad idea putting in a UV dye shot for easier leak tracing later. Of course you can go much further, but depends on the wallet. The R134a conversions up to you, but requires a different oil, and cooling at idle's not the greatest, unless a condensor coil change. If you can believe it, R-134a is being phased out too. Thanks to european union, new, more expensive R-1234yr, will be the next thing.
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
when i did my 79 L82's ac i replaced about everything but the condensor core and evaporator core.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
Thread Starter
Instructor
Joined: May 2011
Posts: 135
Likes: 0
From: Horicon Wisconsin
when i did my 79 L82's ac i replaced about everything but the condensor core and evaporator core.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
Melting Slicks
Joined: Oct 2006
Posts: 2,417
Likes: 336
From: Texas
SH60B, i'll have to look at my adapters tomorrow to see which one is where. there is a smaller one and larger one, believe the smaller one is on the discharge line........ and i think the larger one is at the compressor, on suction line.
when i flushed mine out, i removed the condenser (in front of radiator), first i just flushed it out with the water hose, then used an AC system flush, most auto store have it. poured it in and blew it out with air hose alot!. the evaporator core ( in the ac box on firewall) i poured the flush in it several times and blew it out with air until it was clean fluid that came out. when everything is back together, you need to pull a vacuum on it, did mine for about and hour to boil the moisture out of it.
as mentioned above my next compressor will be a sanden 508 if this one every fails.
when i flushed mine out, i removed the condenser (in front of radiator), first i just flushed it out with the water hose, then used an AC system flush, most auto store have it. poured it in and blew it out with air hose alot!. the evaporator core ( in the ac box on firewall) i poured the flush in it several times and blew it out with air until it was clean fluid that came out. when everything is back together, you need to pull a vacuum on it, did mine for about and hour to boil the moisture out of it.
as mentioned above my next compressor will be a sanden 508 if this one every fails.
Last edited by speedreed8; May 3, 2012 at 10:36 PM.
Advanced
Joined: Jul 2011
Posts: 89
Likes: 0
From: Toledo Ohio
when i did my 79 L82's ac i replaced about everything but the condensor core and evaporator core.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
dont know of way to test the compressor with it off the car. i ended up buying a new compressor , dont mess with the rebuilt ones.
i converted mine to 134A, replaced all the orings, the hoses, drier, orifice tube, and of course the compressor. i had to flush out the evaporator , and condensor cores with AC system flush fluid. also replaced the temperature sensor, pressure switch, and installed 134A adapters onto the service ports. it was alot of work but its been working for 2 years now, and blows out about 36 degree air from the vents.
i also have a light blue 79.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Melting Slicks
Joined: Mar 2008
Posts: 2,989
Likes: 198
From: Meriden CT
[QUOTE=speedreed8;1580723381]SH60B, i'll have to look at my adapters tomorrow to see which one is where. there is a smaller one and larger one, believe the smaller one is on the discharge line........ and i think the larger one is at the compressor, on suction line.
when i flushed mine out, i removed the condenser (in front of radiator), first i just flushed it out with the water hose, then used an AC system flush, most auto store have it. poured it in and blew it out with air hose alot!. the evaporator core ( in the ac box on firewall) i poured the flush in it several times and blew it out with air until it was clean fluid that came out. when everything is back together, you need to pull a vacuum on it, did mine for about and hour to boil the moisture out of it.
as mentioned above my next compressor will be a sanden 508 if this one every fails.[/QUOTE
O.K. Thanks
when i flushed mine out, i removed the condenser (in front of radiator), first i just flushed it out with the water hose, then used an AC system flush, most auto store have it. poured it in and blew it out with air hose alot!. the evaporator core ( in the ac box on firewall) i poured the flush in it several times and blew it out with air until it was clean fluid that came out. when everything is back together, you need to pull a vacuum on it, did mine for about and hour to boil the moisture out of it.
as mentioned above my next compressor will be a sanden 508 if this one every fails.[/QUOTE
O.K. Thanks
Melting Slicks
Joined: Oct 2006
Posts: 2,417
Likes: 336
From: Texas
i had the adapter placement backwards, the red cap larger 134a adapter goes on the discharge line, mine is near the press. switch. The smaller blue cap 134a adapter is on the suction line at the compressor. the red one is at the top of this pic.,,,
Last edited by speedreed8; May 4, 2012 at 07:19 PM.
.
8th Gear
Joined: Feb 2008
Posts: 8
Likes: 0
An easier option is 12a. Systems built for r12 don't cool as well with 134a, but will cool better with 12a. No need to change anything it is a direct replacement. Evacuate the system and recharge. That is if the compressor is still good.
