Stalling Compressor a Symptom of Failing Expansion Valve?

[zigurat]

My 1979 240D has 94,000 miles on it. The air conditioner (York compressor and r-12) cools quite well while moving. However at idle, the belt slips over the compressor pulley and squeals loudly. I had the belt replaced and correctly tensioned, but the problem persists. The shop believes this is due to a failing expansion valve, and wants $300 to replace it and recharge the system. Could a bad expansion valve cause this problem?

[tanktube67]

Originally Posted by zigurat

My 1979 240D has 94,000 miles on it. The air conditioner (York compressor and r-12) cools quite well while moving. However at idle, the belt slips over the compressor pulley and squeals loudly. I had the belt replaced and correctly tensioned, but the problem persists. The shop believes this is due to a failing expansion valve, and wants $300 to replace it and recharge the system. Could a bad expansion valve cause this problem?

The expansion valve has nothing to do with the belt; the expansion valve regulates the circulation of the Freon.
Take a look at the a/c clutch if you see a big gap and if smells like if is burning.
Or take a look at the pulleys may be worm out