Recently the hydraulic pump on my ** 50B literally blew up – it burst open where the high pressure line exits the pump. I have just installed a new pump and decided to replace the filter at the same time. The filter canister had lots of very fine metal filings in it – presumably from the old pump which I noticed was quite worn. I made sure I got all that out before fitting the new filter. With the new pump and filter installed I fired up the machine and have now noticed that when I retract the stabilizers with the motor just idling, when the stabilizer is fully retracted it stalls the engine. I think I may have a problem with the relief valve – perhaps it has some metal filings causing it to malfunction. The service manual shows a place on the “two spool valve” where you can install a pressure gauge, however their diagram is nothing like the controls I have. I’ve attached a picture of the front bucket controls and wonder if anyone who is familiar with these knows if there is a spot on them where a gauge can be installed. Any ideas as to how I should handle this problem would be welcome. Geoff
I'll tell you this first; find out what's blocked or stuck before you run it or you may end up with another broken pump. If you can't find a pressure tap, enter some kind or pipe tee into the pressure line to place a gauge. Then you can slowly open the spool to load the pump and see if it approaches proper relief pressure. Maybe your relief valve is stuck shut or the return line to sump is blocked somehow. As looking at your pic, you could tee in right at the spool inlet from the pump, and you have good access to work with. I have an old Massey 203 that's very similar. Hope this helps.