Need Help with a Pressure Test on a JD 2750 Main Hydraulic Pump!!!

[BuckeyeFarmer1994]

I am trying to run a pressure test on the main hydraulic pump on a JD 2750. Have I circled the appropriate place (in the picture) to attach the pressure gauge?



Incidently, I am trying to isolate why the tractor suddenly lost pressure at on the 3 point and remote outlets. I rebuilt the rockshaft around 100 hours ago, including new fluid, filter and screen cleaning. It has worked great until recently I shut it off after mowing pasture all day. About an hour later, I restarted the tractor and had virtually no lift from either the rockshaft or remote outlets. The remote output pressure is varying between 1,000 and 1,500 psi, so I am wondering whether there may be a piece of debris stuck in the priority valve. I have already tried backing the stroke control valve out then retightening, but that made no difference. I plan to pressure test the main pump prior to taking the prioirty valve out. Any advice will be appreciated!!

 

[Zebrafive]

I would say no that is the non adjustable stroke control valve. You might have backed off the pump shutoff valve, not the stroke control valve.

I would check the priority valve.

Is there a tee up stream from the priority valve going to the steering? That might be the place to pressure test the main pump.

 

[mrmikey]

The only way to test the pump properly that I know of is to connect into the main pressure line with the flowmeter before anything, valves, flowdivider etc. If you go after any valving you also have that to contend with when trying to figure out what's wrong.....Mike

 

[J_J]

You should be able to connect the gage at the input to any valve, and activate the valve and retract a cyl until the relief kicks in.

TractorData.com John Deere 2750 tractor information

 

[medic0648]

Locate the hyd output line/lines on the pump. There should be a little bolt on top of 1 which is the test port. There is also a port for testing the stroke pressure. For my pump the stroke pressure test port was on the mounting end of the pump on top. Otherwise the priority valve can at least give you an idea of where the issue is. Sounds like a seal is leaking and bypassing fluid, your main pump is bad, or the oc feeder pump went out.