Super major Hydraulic pressure

[Andyraines]

Hello all,

Following resetting the lift etc earlier in the year, my '61 super has been pretty spot on over the last few months however recently i've noticed that it struggles to lift anything once the oil is hot (operating temp). Giving the engine plenty of revs just about gets things moving but the hydraulics won't hold up and as soon as you cut the revs, implement will lower to the ground. if I pull the auxillary lever out, the lift will stay raised indefinately.

I pressure tested the system this evening and found that the pressure was a max of 500psi and annoyingly the control valve has started sticking also. As this reading is so low, am i looking at a replacement pump as surely i can't gain 2000psi of pressure by adding shims to the relief valve?

[Kim]

Grasping at straws, perhaps a bit of dirt or chaff in the pressure relief valve? I'd call for a new pump as a last ditch solution. I'm sure you will hear a lot more on this forum from others far more experienced than I am!

[Dandy Dave]

Yes, Check the pressure relief valve first. The spring may also be broken. Dandy Dave!