Testing a hydraulic pump

[Alesandro]

I got the used pump today and it's a little dirty on the outside (expected), no biggie. Can I completely open the pump and inspect it, or will I need to buy new seals once I crack it? I would like to look inside of it before installing it.

 

[mrmikey]

Best bet is to put it on the main pressure line into the valve, that way you can test each section without having to move the gauge around. Not sure of the pressure, I'd say 12-1500+, if someone tells you different, believe them because I'm not sure of your system.............Mike

 

[mrmikey]

Can I completely open the pump and inspect it,

And you would be looking for....... Unless the defects are blatantly obvious you're not going to see anything.............Mike

 

[wdchyd]

And you would be looking for....... Unless the defects are blatantly obvious you're not going to see anything.............Mike

x2........and if the defects are blatantly obvious the pump is junk anyways

 

[DLTTrekkers]

Checking the pump by inserting a gauge at the external brakeaways ...start the engine and let it idle ...note the pressure....take the revs up and note the pressure and now by holding that pressure there decrese the revs and note the pressure....if pressure drops with revs dropping ...to me it means a backflow of oil throu the pump....that pump needs replacing

 

[dfkrug]

I got the used pump today and it's a little dirty on the outside (expected), no biggie. Can I completely open the pump and inspect it, or will I need to buy new seals once I crack it? I would like to look inside of it before installing it.

I would open it up to see if it is clean inside. Used pumps may not have been protected from
dirt getting into the open ports. You can see if it is damaged inside by dirty fluid: look for
scoring. Furthermore, cavitation damage and bad seals may be visible (photo).

I tend not to trust used hyd pumps, motors, valves.

 

[Alesandro]

I would open it up to see if it is clean inside.

dfkrug;
What caused the marks in your provided pic? I want to open it but the only thing I need to know is will I need to new seals that I might not be able to replace, then I would still need another pump.

After talking to a couple facilities here about getting my pump tested they will all open the pump and visually inspect the condition of the pump and to verify there is nothing in the pump that could damage their equipment.

I personally would like to open it and take measurements, see how it works, and stuff like that. I was the kid that took about the drill to see how it worked.

 

[Alesandro]

Checking the pump by inserting a gauge at the external brakeaways ...start the engine and let it idle ...note the pressure....take the revs up and note the pressure and now by holding that pressure there decrese the revs and note the pressure....if pressure drops with revs dropping ...to me it means a backflow of oil throu the pump....that pump needs replacing

Thank you for suggesting this method and I will try it. One question I have is would it hinder or be bad to get a gauge, tee a line off one of my cylinders to my gauge and mount it so I could always visually inspect the pressure, or, once the system is in full working order would it even be needed?

Thanks for the help guys.

 

[dfkrug]

dfkrug;
What caused the marks in your provided pic? I want to open it but the only thing I need to know is will I need to new seals that I might not be able to replace, then I would still need another pump.

My theory on the failure was the user was operating tractor on relief for an extended period
and overheated the fluid.

The simplest pressure test uses a gauge at the end of one working port hose, often on the
loader. No Tee plumbing required.

 

[Alesandro]

dfkrug;

My thoughts for the tee was to keep it on either permanently or until I get this issue figured out. When I 1st start up the bucket works fine, (I pressume I have all the hydraulic pressure I am supposed to have), after a while it slowly loses hydraulic pressure. One thing I forgot to mention that when it gets to it's weakest point, the bucket will actually start to lower in between my shift from pushing my lever all the way up back down to middle. I hope I explained that correctly. Meaning if I have a load that say is 3' high and that's the farthest it can go, then when I put my lever back to center, there is a short time that the load will actually start to lower, before I hit center.

I was thinking about having the gauge mounted and I could monitor my pressure, then as everything starts to warm up I assume I could watch it drop. I read another place where my MT 372 D hydraulic pressure should be 1950psi. If I am not even getting that from the get go would that not help pin point the issue as well.

Thanks for all the help.