Shifty, when you jump the compressor clutch, can you here it click when the engine is not running? If it does, try it with the engine running and try to determine if the compressor is actually running. If the system uses R12, you have Schrader valves for test ports and the low pressure side may be stuck, or not being opened by the charging hose. If it is a Schrader valve, try depressing it with a small screwdriver to see if it has some pressure. If the system is 134a, a gauge set will be required to trouble shoot it.