I had the same problem as yous: It's definitely the compressor. And No, you don't have to replace the whole compressor, it may be a little part of the compressor called 'compressor AC switcher', it's inside the compressor itself.

You also should put 'thermostat' to cut off the compressor line when it reaches certain temperature.
TERMOSTART

Replace the dryer to solve the nasty smell.
http://farm5.staticflickr.com/4131/4...68656373_b.jpg