No Rear Hydraulics for BH65 and 3PH

[Ottawa King]

I appear to have lost all hydraulic pressure to the 3PH and BH65 (tractor is a B2920). I haven't checked the pressure yet (will fetch a gauge and do so) but there doesn't seem to be any fluid going past the QC (I disconnected it and pushed the detent in as it was running). The FEL cycles fine. There was no indication of failure (no fade, no smells, no crunching noises, nada). The backhoe was working fine all day. The problem appeared after I loaded the FEL up with yard waste, dumped it and then positioned to scrape some more with the backhoe. The legs wouldn't lower, nor would the backhoe work. Tested the 3PH and no joy. PTOs also work fine as does the HST. No funny noises from the pump or valves. Very frustrating.

PLEASE HELP!!

 

[BeezFun]

I'd remove and reattach all your quick disconnects to make sure they're properly connected. If the same one is a culprit, try switching hoses on connectors to see if anything changes and narrow down which connector/fitting isn't working properly.

 

[Ottawa King]

I'll give it a try. Thanks.

 

[J_J]

Where are you getting the fluid for the BH, a PB source, or a valve work ports?

If you have your hoses connected correctly, with all valves in neutral, the fluid is flowing from pump to tank.

You say the FEL is working, so there is a complete path from pump to tank.

If you are getting the fluid from the PB port. then the fluid is flowing through the BH valve to tank.

If you are getting the fluid from the remote work ports, do you have the remote lever in an open position, either in detent of bungeed on.

Check all them QD's again.

If a QD was locked closed, or disconnected, the relief valve would be going off.

 

[Ottawa King]

It's somewhat difficult to tell, JJ. The main distribution port for the hydraulics are off a multi-port manifold on the right side. It's a pretty stock set up. It appears the FEL and BH65 take their hydraulics from this remote work port, which looks to be fed from a line just forward of the left lifting arm and thus the main hydraulics for the tractor. From the manifold, one line goes forward to run the hydraulics for the FEL, the other loops back under the rear diff/axle and up to a QD behind and under the seat. I will take a closer look for the other line, and will also check the settings. I never touched anything between it working and not working, so it's possible I inadvertently knocked something, or something failed, or? It's confounding and very frustrating. I appreciate all the help and quick responses. Will keep you posted.

 

[sandyc]

is the tph lock still in place? did the tph inadvertently get raised?

 

[Ottawa King]

There isn't a lock for the tph lever. There is a detent at full up or down. It was in the raised position during normal operation. I used the lever to raise and lower the arms in order to check if they were also affected. They are moveable by hand regardless off the position of the lever.

 

[beckmurph]

The 3ph lever should be in the full down position. There should be an L shaped lock and black plastic knob that holds the 3ph in the lowest position.

 

[J_J]

I am thinking that somehow, the PB line and tank line got switched, and that would have the PB going to tank, and that would allow the FEL to work but not the 3pt or BH?

 

[Ottawa King]

They were never removed or adjusted since new (349hrs ago), so it's not likely they've been tampered with. It may be possible that an obstruction or valve malfunction could cause the problem.

Kubota tech said that it may be possible that the FEL valve or the distribution valves on the back may be shunting pressure due to being open. This might cause a bypass that prevents pressure from building in the backhoe or 3PH.

Going to comb through it tonight and see what I come up with. Wish I had a pressure gauge. It's on the top of the list, in addition to a service manual.