So I have a US MF 135 gas deluxe and the hydraulics have been giving me fits. I think there is something wrong with the control valve but despite having the Massey and I&T manual. I don't know how to isolate the problem.
The tractor at one point had a pressure control valve but it was taken out without my knowledge. It still has the welded block on the standpipe. I also have a remote valve usually in lieu of the standpipe cover. I took that valve off to make sure those o rings hadn't failed. I replaced the one on the top end of the standpipe and reinstalled the cap.
If I use the remote valve to raise and lower the three point linkage generally speaking it'll work. However, if you were to lock the valve lever back to use the quadrant levers after a few times it gives up the ghost if you will.
If I take off the response control inspection cover and drain the oil down, even with a Ferguson AO plow the relief valve does not blow. However, with the remote valve installed on the top cover oil looks like it spews from the top cover if you have the remote lever pinned back and have position control lever to transport.
Also when draining the oil and if you jiggle the control lever inside the pump it raises the linkage up and down if you control it by hand.
The knuckle on the draft control spring feels loose as well. I've been planning on replacing it due to the boot coming off.
Any ideas on what I've missed? I've read the manual almost every night for the last two weeks and I'm not sure where I've made the mistake at.