test an AC compressor?

The AC in my '77 does not work. Big surprise. When I turn it on, the blowers work, but the clutch does not engage. I know that if the freon is low, the clutch will stop as a safety. Is there a way to make sure the compressor is good or bad before filling it with $$$ r-12.

 

There are 2 ways to do this. One is to pull the wire at the AC compressor and give it +12V and listen to see if the clutch engages. The other is to remove the spare tire cover and coming out of the receiver/dryer you will see a switch with 2 wires running into it. Jump the 2 wires and listen for the compressor clutch to engage. If either of those make the clutch engage the that part of the compressor works. Then I would attach an AC gage on the low pressure line to see if you get a reading. If not you are out or low on freon. Good luck.

 

Is there any maintenance, or preventive maintenance, required on the a/c compressor? Similar to how we remove the water pumps and alternators to change bearings, seals and what not, is anything similar in nature required on the compressor?

Just curious, mine is out of the car right now as I service the car, I would want to tackle anything now before I put it back.

Thanks,
Phil

 

In a recent thread I learned some compressors have a separate oil sump requiring xx oz of ac oil. Normally ac oil in the gas lubricates compressor upper end.

Thread:http://www.ferrarichat.com/forum/showthread.php?t=247886