JDD 455 charge pump issue

[BrisMatt]

I have a jd 455 which has a problem with the mid PTO, ie the mid pto is not powerful enough to spin the deck. I have run a mid pto engagement pressure test and it passed, I then did a Charge pressure test. The charge pressure was 250psi (should be 285 psi) and the pressure test with the implement relief on was only 700 psi (should be 924psi). Does anyone know why the implement relief pressure is well below the recommended yet the normal charge pressure is almost at the recommended pressure. I know the charge pump is a likely cause, however I want to make sure as this is a costly item.

 

[XSKIER]

Those test results are close enough for a 11+ year old tractor. If you have the pressure at the engagement solenoid, your PTO clutch is likely slipping. Either from a broken part or burnt clutch linings. When I've seen charge pump trouble before, the PTO would slip while trying to drive the tractor, but be ok while stationary.

 

[BrisMatt]

thanks, I'll have a look at the clutch