Vintage Air issue

[Z06killinSBF]

This is an older issue for me but I might as well fix it. Last summer I installed a Vintage Air kit on my Mustang. It work for a few months and then the car sat for about 3 months. When I tried to use the A/C again it wouldn't work but when the compressor would cycle, the whole car vibrated and it made one hell of a racket. I havent tried it since so that I dont think I messed anything up. Any ideas?

[Rhino]

Have you put a set of gauges on it? If so, what are the hi and low side pressures?

Given the fact that the compressor would vibrate I would put my first look into checking to insure the system wasn't over filled with either refrigerant or oil. When overfilled you'll get liquid sucked into the compressor, causing it to shutter.

[Z06killinSBF]

Does that cause damage? Can I just vent some off?

[ErikLS2]

Don't just vent some off (which you shouldn't do anyway) until you know what the pressures are like Rhino said. The compressor isn't just loose is it?

[Z06killinSBF]

I guess I meant would I need to totally evac the system or not. Everything is tight.

[ErikLS2]

Don't have to totally evac the system no, you can just recover enough to bring it to the proper charge level.

[Z06killinSBF]

Can someone do me a favor and measure the resistance on their VA compressor? Mine is reading 0 ohms across the board and we believe it to be shorted. That would lead to the compressor being bad right?

[KUL FIR CHICK N]

Please call VA for help. You should never try to adjust the charge without the proper equipment. It sounds like the system may be overcharged. You should always charge the system by weight and you need to have gauges on the system to troubleshoot. If you're overcharged, you need to evacuate completely and start over. This is a job for a shop with a charging station because they need to measure how much refrigerant and oil was pulled out. You have to add back any oil that comes out during recovery.

[Larry Callahan]

I agree on possibly over charged. I did the same thing to my truck.

[Z06killinSBF]

Well, we did some head scratching and seem to think that the dash switch possibly arced and is causing a high resistance. I bought myself a SPDT 30A relay to wire inline after the pressure switch to power the compressor.