Need Help with Ford 19-390 hoe (755 series)

[Eric_284]

Hi All, I picked up an old tractor with a FEL and Ford backhoe attachment. Tractor runs good but the hydraulics leak like crazy, especially from the hoe valve body. Can anyone help me identify what these fixtures on the front (when looking from the seat) are, what they do, and what is generally involved in fixing them? This is by far the worst area for leaks. Steady stream from the one labeled 35 when the hoe is in operation, and drips when everything is off. Thanks

 

[JL Sargent]

Pressure relief valves and set for 3500 and 2350 PSI? The one on the opposite side set for 4000psi.

 

[mekanik]

Is the oil leaking from the acorn nut and lock nut under the acorn nut?
I would expect that there should be copper washers under the nuts to seal them.

 

[Eric_284]

Is the oil leaking from the acorn nut and lock nut under the acorn nut?
I would expect that there should be copper washers under the nuts to seal them.

It looks like its coming from beneath the washers/nut, against the valve body itself. It pretty hard to see exactly because its a such a mess in there and there's pretty limited access. Are these something that can be unscrewed or are they in there for good?

 

[Eric_284]

So over the weekend I took the valve off thinking there was an issue with an o-ring. Turns out there is so much wear from the elements that there is actually a pinhole in the side of the valve body. Anyone have a good source for obsolete parts? Tried New Holland dealer and even called the corporate help line, both told me the part is discontinued and was not superseded.

Alternatively, does anyone know if there are other brands that will fit? Doesn't seem like relief valves would differ all that much in terms of how they operate, regardless of who makes them.

 

[JL Sargent]

If it were me, I would research the idea of plugging that pin hole if possible. I wonder if you could drill and tap it for a plug for instance? Maybe it could be brazed? Others here may know where to source that part.

 

[Eric_284]

I just picked up some brazing rods today, that's my Plan B if I can't find a way to replace it.

 

[Tinkerer]

Good luck on brazing it if it is cast-iron.
Brazing cast valve bodies was always a dismal failure for me.
You may be able to find a salvage yard that will sell you the entire valve or just the section that has the hole in it.