1983idi
Registered User
I decided to try and fix the ac on my truck since from what I've read your mileage drops just about as much having the windows down as running AC on the highway and AC is way cooler air and not as noisy. I pulled a vacuum on my AC system to try and find leaks but strangely the 40 year old AC system held vacuum without issue.
Since it held a vacuum with no problem I figured I'd charge it and see what happened. I emptied 1 12oz can into the system not running and then turned the ac on and added 2 more 12oz cans. The low side pressure got to 30 psi on the second can but didn't go up anymore when I added the 3rd can. AC blows nice and cold in the truck but the compressor clutch is always running and engaged.... On old systems like this is the compressor just always on when the AC is on? Anything else I have worked on the compressor cycles on and off? Is 36 oz of refrigerant not enough and that is the issue or is something else wrong?
Since it held a vacuum with no problem I figured I'd charge it and see what happened. I emptied 1 12oz can into the system not running and then turned the ac on and added 2 more 12oz cans. The low side pressure got to 30 psi on the second can but didn't go up anymore when I added the 3rd can. AC blows nice and cold in the truck but the compressor clutch is always running and engaged.... On old systems like this is the compressor just always on when the AC is on? Anything else I have worked on the compressor cycles on and off? Is 36 oz of refrigerant not enough and that is the issue or is something else wrong?