|
Fact is, every part of the hydraulic system is being stressed when its holding the three point up. The pump, the pump valves, the pump control valve, the pipes, the o-rings, the pressure control valve, the pressure relief valve, the lift cylinder, the lift cylinder piston, and the lift cylinder rings. And today with the tractor being as much as 43 years old, every one of those pieces is worn. And some of what was elastomeric is now hard and wearing faster. Looking at the parts book and the I&T manual, the pressure valve assembly is bolted to a plate that hangs down from the rock shaft assembly and parts of it are intertwined with other pieces of that assembly. Getting it unbolted and unplumbed working through the side hole would be extremely dfficult and may leave pieces in the bottom of the housing, especially bolts and nuts. Putting it back would probably try the patience of Job. There is no access from below. I question it being the pressure relief valve any way because if it was leaking, it might not get enough pressure to lift the load on the three point. I think its most likely the piston rings on the lift cylinder or something to do with the pump, like debris in the pump valves or worn pistons there. Remember with the three point loaded and parked all those parts have to hold pressure and work just like the tractor was running. Many makers of such equipment clearly say, "Don't park it with the load raised." And if any such pressure loaded part fails that load could come down rapidly breaking it when it hits the ground or you if you happen to be in its way. My MF-135 leaks down. If I want to keep the three point load off the floor I put a stack of pallettes under the load and rest it on that. Gerald J.
|
