talquinmax

[talquinmax]

Just put new hydrulic pump on '86 JD 750 compact tractor with front loader/backhoe. Replaced old pump because of weak operation and loud whining noise. New pump is stronger but still has whining noise. Not as bad as old pump but still there. Has all new hydrulic oil in system. All valves are open. Can anyone advise?

 

[J_J]

If it is whining, it sounds like it has a load on it.

Install a 3000 psi pressure gage and check the pressure with all levers in neutral..

It should be 0 psi or very low pressure.