Testing my hydraulic circuit on my M-444

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mrfixer

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Not sure what happened to my earlier post... so here it is again

I have a '63 - '65 M-444 - the engine on it has seized, so I pulled it out. While I'm shopping for a replacement motor I wanted to test/assess the hydraulic system. Since the unit wasn't running I know nothing about is operation, leaks, etc. Is there a way one could test some of the components individually? I thought if I could spin that hydraulic pump some way, I could build the pressure in the system and be able to test the directional valves, cylinders, etc. I have a Jet electric motor, 2hp 1750rpm that can spin Clockwise or CounterClockwide. If I could fashion an adapter that mates to that splined shaft on that pump could that work for testing individual circuit branches in the system?

Danger, cautionary tales, etc - are welcome
 
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mrfixer

mrfixer

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I built myself an adapter using a spline connector from the old Onan CCK. I'll attempt to temporarily spin my hydraulic pump with this contraption:
 

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mrfixer

mrfixer

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Wish that shaft was a strong flexible kind so it would be easier on any minor mis-alighment with the pump. I've read the pumps wear out faster if they are not aligned well.
 
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mrfixer

mrfixer

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My pump: Webster OHCS... that's all I can make out - can anyone help figure out what it is and where I could get a rebuild kit for it?
 

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mrfixer

mrfixer

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I hooked up my make-shift electric motor via the custom adapter to my Hydraulic pump and ran it for a bit. I leveled it pretty well and turned it on an off briefly with loose bolts so it would 'settle into place', then tightened everything down. It was scary as he&& at first to run it. I wasn't sure what was going to be coming out through those old hoses and fittings... I was wearing full face shield for protection as I peaked here and there, but it all stayed together well. Only ran it for few minutes, but after checking for leaks I was able to move the boom up and down via one of the control valves. I then curled the bucket in and back out few times. All seems to be ok so far - no leaks tonight. Hope same in the morning - I'm thrilled to have done this simple test - at least I know s o m e t h i n g works on this old girl.
 

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mrfixer

mrfixer

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Now I know things work, but don't know how much pressure the old pump is producing.... could be good could be weak, can't tell. Where do people plumb a pressure gauge on these? I do have the auxiliary connectors on this old unit, if I can figure out what type it is, it would be a good temporary place to measure it.

That caliper reads .925''
 

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