hydraulic lift

[tyrone brown]

Completely tore apart the pump replaced safety valve. Added new rings to piston. Lift goes up but when clutch is engaged or engine is turned off the lift goes down really fast. Checked pump for leaks and cracks, no cracks or leaks found. What do you think is the problem?

 

[Dell (WA)]

Brownie.......FIRST thing to do with hydraulic "issues" is to remove the 6-"roundy dipstick plate behind yer right heel and look fer "squirts" while lifting an implement. But based on yer complaint, "goes down really fast", I'd say yer new safety valve is stuck OPEN ......Dell

 

[JMOR]

Clearly a leak, as stopping the pump it should hold, but only stays up with pump running to replenish the leaking fluid. There are 9 possible leak points, besides such biggies as cracked castings & the like.