We are facing hydraulic oil leakage problem inthe 962H wheel loader control valve(M/c.Sl.No:MAL00124),we have replaced the o-rings several times but after few hours of operation o-rings get damaged particularly in the lift control valve(P.No:253-4025),more over there is drift in the lift cylinders.So please advise
First off, 2354025 doesn't show up as part of your machine. It should be part of a N4A prefix machine, but that's not that important right now. From what I can see, there's nothing particularly sexy about the O rings in the control valve on your loader. So the question is, are you using genuine Cat O rings and are you torquing the through bolts correctly? (50Nm plus 180 degrees)
Also if we're talking about o-rings getting damaged in just a few hours of operation have you checked the operating pressures in the implement hydraulic system..? When you talk about drift in the lift cylinders do they start to drift immediately after you have installed new o-rings in the control valve or does the drift start around the time that the o-rings start to leak..?
The machine prefix is MAL, Control valve Part No is 2610019,We are using genuine cat O-rings, and we have torqued the bolts with 50NM+180 deg.
The high stall pressure is 4000psi,there is no momentary drift after fitment of the O-rings, but when the control lever is in hold position there is a drift in the lift cylinder.
Pull the spool out of the lift side of the implement control valve and inspect the spool and the vavle body. Based on previous experience with 962H you will probably find that both are scored.