Tractor Repair: case 885 xl 4 wd, piston seals, 4 wd

Question
problem .rear hitch/lift arms drop 5 mins after tractor is stopped.trailer tipping is perfect.steering is perfect.it seems ther is a big oil leak on either the piston or piston relief valve

Answer
Hello,

  Either the piston seals are leaking, or if the lift cylinder has a cushion relief valve, it could be leaking.  It could also be a sticking spool or check valve in the hitch control valve.  No matter which of these is the problem, the lift cover will have to come off to get at everything.  While it's apart, do an air check with compressed air and a rubber tipped blow gun to find a leak in the control valve.  Make sure all spools in the valve move smoothly with no sticky spots.  To check the piston, it will have to be removed and the seals inspected or if in doubt, just replace them.  Look for any scoring on the inside of the cylinder also.

                   Good luck,

                          Arnie