When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hi, I’m driving my 76 cross country to attend my mother’s funeral in Missouri this week.
my AC blew cold since I purchased the car in November and it appears to have several new/upgraded parts.
it stopped blowing cold this week, probably because I disconnected a wire when I was changing the spark plugs and trying to upgrade to a 1984 style squirrel cage fan. I ended up putting the old one back in because of some fitment issues with my homemade spacer. I do not see any loose wires.
I have not had time to check if the compressor wire has power. I have a refrigerant can with a gauge so I checked the pressure and it is in the red and says retard - same pressure when the motor is running or not.
any advice is much appreciated. It’s cool enough with the windows down but unbearable in town. It is 85 in West Virginia. I’m planning to stop in Bowling Green for a quick visit to the museum so maybe I can find a shop to diagnose it there.
Hard to tell exactly what is going on here from your photos. I can tell you this much.
Your system has been upgraded to a Sanden compressor and 134 refrigerant.
I really can't see other components. Or tell how things are wired for that matter.
Your gauge reading means nothing to me.
If for some reason you unplugged a wire or wires. Plug them back in. As per your blower motor conversion. Fix your spacer and get that done. It's really worth the effort.
For pressure to be that high on the low side your compressor has to not be running.
likely you're low on freon. As a protection feature for the compressor the system will not run when the freon is too low, leading to a reading such as yours.
Thanks @4-vettes and @REELAV8R , I appreciate your advice. I dropped the car off today at a an auto AC specialist in Columbia, Missouri, so hopefully he will have it back to me tomorrow. I ended up skipping the National Corvette Museum so I could get to Missouri to have more time for the car to be repaired.
The car ran flawlessly from Marylaand - the temperature gauge ranged from 200-210, and with the 5 speed Tremec and Atomic EFI, I averaged 17mpg at 70-80mph.
Is that a ZZ4 engine, or similar? At any rate, those heads are not stock. Which is good news.
It appears someone added a manual valve to the heater hose. While the orientation of the handle may indicate that it is closed (good for summer!), you might want to check that too.
If this is all stuff you already know, thank you for coming to my TED talk.
Yes, those are Flo-Tek heads that came with the car. I got the car in an online auction (Copart) so I wasn't able to get any information on the heads and I can't find any casting number, just the Flo-Tek symbol and a date code from 2013.
It appears someone added a manual valve to the heater hose. While the orientation of the handle may indicate that it is closed (good for summer!), you might want to check that too.
I added 2 manual valves on the heater hose. That reduced the heat in the cabin quite a bit. I checked those valves this morning and one does not look closed but it is.
If this is all stuff you already know, thank you for coming to my TED talk.
I'm always appreciative of everyone's advice on this forum
Just to close out this thread, AJ's Automotive Air Conditioning in Columbia, Missouri, did a great job on my AC. As I suspected, when changing the spark plugs, I pulled loose a butt-connector in the compressor wiring. AJ also checked the refrigerant level and fixed the high speed on the fan. The trip back to Maryland will be much more comfortable. Thanks to everyone for their advice.
My AC is Retarded?
