Tractor Repair: ac problems, thermostat switch, balance shaft

Question
Happy Easter. I recently purchased a 648g skidder and had a few minor problems that I have resolved. The problem now is the ac compressor will not come on unless hot wired. I vaccumed the system down to about 28 in. and put in about 3lbs. of 134A I did not have time to check for power at the switch The blower works fine in the cab, and the condensor fans work fine. I am wondering if the high pressure or low pressure cutout switches could be bad.I do not have access to wiring  diagrams for this tractor. and do not see a fuse or relay in the electrical center. By the way thanks for the answer re; the balance shaft bushings on the 4045T engine.

Answer
It is either your thermostat switch or one of your pressure switches. You can hook up your pressure switch connectors together to bypass them if suspect one is a problem. But you are going to have to check for power at the switches. if there is no power then it's a fuse or the thermostatic switch.