[m1782t]

when sitting in idle for an hour and a half the compressor never shut off, when driving the ram air thru the condenser cools faster than the fan does at idle so the compressor cycles more often, if the air gap on the clutch is in limits but really close to the high end it won't always have the magnetic strength to engage, I made a new spacer .015 thinner than the one that was in there and so far it has worked consistantly. I guess that must make me a professional - at least I didn't need special tools (other than my lathe) and I didn't hurt myself.
If you are having the same problem, what I did was to drive a country road until it started blowing warmer air, I pulled over imediately, popped the hood and the clutch was not engaged, I had a stick in hand (another specialized tool) ready to tap the clutch, I just touched the clutch and it engaged, telling me it was trying to engage but couldn't pull it that far.