B7100 Hydraulic pump pressure weak.

mauser1111 · Apr 21, 2018

The tractor is the later style b7100, and the pump I am refering to is the engine mounted hydraulic pump. I have afront end loader. The loader is a woods dual. I put a pressure guage on the loader. I can not get the pressure bove a about a 1000 psi. I have turned the loader relief valve in all the way and I also have taken the relief valve apart on the tractor 3 point control valve. Neither had any dirt or looked to have any wear. I tried shimming the tractor relief valve but it seemed to make no difference. The odd thing is I cant get the 3 point hitch to go into relief. I have a 3 point backhoe on the three point and I use it as a test object to lift. It is mounted ao that the three point hitch is restricted from moving up. Shouldnt the three point pressure relief squeal when it is lifting more than it can handle. Does anyone have any thoughts on this? Possibly the pump is weak. Can the hydraulic pump get weak where it just produces less pressure but isnt showing any leaks. Im not getting any air in the system either. Thanks for any help.I have very recently changed the fluid and used Kubota fluid, kubota filter and cleaned the screens.

bigdeano · Apr 23, 2018

Try checking the pressure at low RPM and then at high RPM. A worn pump will develop less pressure at low RPM. Did this problem start suddenly or gradually? Are there a lot of hours on the tractor? If so, the pump could just be worn out.

Xfaxman · Apr 23, 2018

How and where did you put the pressure gauge on the loader?

mauser1111 · Apr 25, 2018

The problem seemd to have happened all of a sudden. I teed the guage in the the line from the loader control valve to the base end if the curl cylinders. That is where the dual 145 loader owners manual stated to check loader pressure.

Dave M7040 · Apr 25, 2018

Could you please provide some more history. A problem suddenly occurring is indicative of something other than wear.
More likely flow and pressure arev being bled off and thus keeping overall system pressure low.

When you say later B7100 is yours one whose WSM is in Kubotabooks.com ?

When you bought the tractor, did it have the FEL on or did you add it?

Are you using the Kubota hydraulic block to get hydraulic flow and pressure for an additional implement i.e. FEL? Backhoe?

How many hoses are on the FEL valve block? 6 or 7.

Some photos showing the overall side, back and front of the tractor will help.

Were any lines removed from the FEL valve at any time?

You mention a 3 pt backhoe. How does this tie into the hydraulics?

Dave