Hi, been working on my Oliver 770, came across an issue, thought I'd post symptoms, and get some thoughts.

tractor is fitted with a Ware loader/backhoe.

I changed the fluid in the resovoir, and the filter (return line type).

Fluid was milky, and filter was really nasty.

With fluid topped off, symptoms are as follows:

No unsual noise when running, and all spool valves in neutral.

When raising loader, a terrible noise comes from the loader valve, sort of a low pitched screech, and the loader seems slow to me. I say seems slow because this machine is new to me.

Lowering loader makes no noise, and I have enough down pressure to raise front end off the ground.

Backhoe swing cylinders, and boom work fine, and stabilizers can raise rear of tractor quickly, no strange noises, so I figure pump pressure is ok.

dipper stick cylinder is very slow, but no strange noise, so I think that's just a worn piston seal. Backhoe bucket cylinder has a bad leak, so I am not testing that for now.

Based on the above, anybody have any thoughts?

Thanks,
Steve.