Hi All. I've got anearly E12 based 633. I'm having trouble with the AC system. I've changed out the receiver and charged with R134. When I turn the temp control knob to the cold area the blower comes on but the compressor doesn't kick in. This system does not have the press. switch like newer models. Is there any other reason why the clutch might not kick in other than the fact it might be toast? I've put three cans of refrigerant in and have had no luck. I do have a wiring diagram for the system but it hasn't been much help as I don't know where all the components/relays are. Any ideas or suggestions from you early sixer owners?