All hydrolics are slow but just rebuilt main hydrolic pump and the charge pump is good also. But still is slow moving as in grapple moves slow steers slow dont know what else to do. Any suggestions? Got to be something simple.
Piston pump? What is the differential pressure?
Did it start happening all of a sudden? Have you checked for pinched or a eternally collapsed suction line. Suction line filter restricted? Perhaps a steel portion of line between the pump and controls that got a stick into it and bent it enough to restrict flow. I am assuming you have proper pressure and just slow flow?
Havent checked differential pressure but got pressure gauge on main pump have 1800 lbs but when I try to use grapple it drops to 0 and if you speed motor up to make the pump move faster it slows down more.
Is 1800 the spec? that sounds low but I don't know. Have you checked the charge pump pressure, both idling and when you try to use a function. Apparently this is the JD radial piston pump system. It won't do anything without charge pressure so all of OldIron's suggestions are good. An INTERNALLY collapsed suction hose, if there are any suction hoses, would do it. It looks like there's a filter in the hydraulic reservoir, so that would presumably be a suction strainer and would cause your problems if it's plugged. I'm just looking at jdparts, no actual knowledge is at risk.
took the oil filters out of the tank didnt look that bad the pump is suposed to have 2400 got to be clogged up somewhere but cant find it when you apply the grapple the pressure goes to 0 on the main pump gauges
Is that charge pump mounted on the engine? does that have a rubber suction hose going to it? Even a crack that's letting it suck air could cause your problem in this cold. Not knowing the charge pressure, I'd follow the oil. If the charge pressure is OK at the pump when you use a function, then and only then I'd look at the pump.
charge pump should have 200 -240 psi, main pump should have 2250 psi, I have seen the seals go in the charge pump and they do not leak oil out but it sucks air in, after it has been running is the oil in the tank full of air bubbles ? did you change the two filters between the rad and grill ? Does this machine have the round main pump or the square main pump ?
yes the oils is full of air bubbles but they have looked at it and didnt see anything wrong with it but didnt go any farther with it either.