Land Rover Repair: WIRING P38 COMPRESSOR PUMP, piston seal, piston ring

Question
QUESTION: HI
IVE GOT A P38 COMPRESSOR PUMP THAT IM PUTTING ON A DIFFERENT CAR BUT NOT FIRMILULAR WIV THE WIRING BLCK GRREN AND ORANGE COULD U TELL ME WHICH IS LIVE AND WHICH IS NEGATIVE ETC
MANY THANKS
ROSS

ANSWER: black is ground (negative)
Green is Live
Orange is the thermal overheat switch output, closed to ground is good, open to ground is overheated.




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QUESTION: another quick question ive found out the piston seal needs replacing but not sure how the piston comes apart to replace the seal could u explain how to take the piston apart please
many thanks
ross

Answer
the ring above the piston comes up off the top.  A sharp knife wedged into it will slowly pry the ring up.  I have instructions for my seals here:

http://www.rover-renovations.com/kb_results.asp?ID=25

and the seals here:

http://www.rover-renovations.com/Air-Suspension-compressor-piston-ring-p/anr3731

A very useful tool for seal removal here:

http://www.rover-renovations.com/Tubing-Cutter-p/vf-32.htm