B6200E Hydraulic Problem(s)

[PaulinBft]

Before I begin, thanks again to those who helped me here recently.

My B6200E had been sitting for a few months and when I tried to use it it sprung a few hydraulic leaks, the worst being the seals on one of the bucket tilt cylinders. Also, two hoses had sprung pinhole leaks and evidence of another leak appeared in the neighborhood of the hydraulic pump (although I couldn't see it, just the oil running down the block behind the pump.)

I rebuilt the bucket cylinder with parts on hand and ordered parts to rebuild the hitch cylinder and to replace the pump banjo fitting seals and o-rings. But when I tried to move the bucket, no jomy. It tilted up once but then wouldn't tilt either way.... i.e. the hydraulics couldn't tilt it.) When I turned the engine off the tilt lever, assisted by gravity, allowed it to tilt down.

I drained the oil and cleaned the screen on the suction line, thinking maybe the filter was interfering with oil circulation. (It was dirty but not extremely so.) And when the parts arrived I replaced the leaky seal on the rear cylinder (which hadn't been able to keep the box blade off the ground for more than a half minute) and the seals and o-rings on the pump banjos.

I refilled the transmission, started up the tractor and let it run for a few minutes. Then, eager to test the hydraulic repairs, I raised the box blade .... it rose and then the tractor stalled. Subsequent attempts to get it running failed - it would fire briefly than die. What I suspect is that something is loading down the pump by impeding the flow of fluid which is bogging down the engine to the point of stalling. It will turn over and fire but only very briefly. Perhaps a relief valve?

I don't know where to go next. So I am seeking more advice here. I'd appreciate any thoughts on this.

Thanks,
Paul

 

[North Idaho Wolfman]

Yep, your dead heading the pump.
That's probably the reason for all the leaks too.

You'll need to provide some pictures and Hose / line routing info as to how the loader is hooked up because more than likely that's where your issue is.
A picture of lines with numbers on them is the best for figuring out what goes where.

 

[Dave_eng]

Before I begin, thanks again to those who helped me here recently.

My B6200E had been sitting for a few months and when I tried to use it it sprung a few hydraulic leaks, the worst being the seals on one of the bucket tilt cylinders. Also, two hoses had sprung pinhole leaks and evidence of another leak appeared in the neighborhood of the hydraulic pump (although I couldn't see it, just the oil running down the block behind the pump.)

I rebuilt the bucket cylinder with parts on hand and ordered parts to rebuild the hitch cylinder and to replace the pump banjo fitting seals and o-rings. But when I tried to move the bucket, no jomy. It tilted up once but then wouldn't tilt either way.... i.e. the hydraulics couldn't tilt it.) When I turned the engine off the tilt lever, assisted by gravity, allowed it to tilt down.

I drained the oil and cleaned the screen on the suction line, thinking maybe the filter was interfering with oil circulation. (It was dirty but not extremely so.) And when the parts arrived I replaced the leaky seal on the rear cylinder (which hadn't been able to keep the box blade off the ground for more than a half minute) and the seals and o-rings on the pump banjos.

I refilled the transmission, started up the tractor and let it run for a few minutes. Then, eager to test the hydraulic repairs, I raised the box blade .... it rose and then the tractor stalled. Subsequent attempts to get it running failed - it would fire briefly than die. What I suspect is that something is loading down the pump by impeding the flow of fluid which is bogging down the engine to the point of stalling. It will turn over and fire but only very briefly. Perhaps a relief valve?

I don't know where to go next. So I am seeking more advice here. I'd appreciate any thoughts on this.

Thanks,
Paul

Please look at the following page from the Operators' manual and tell us if this is how your system is plumbed up.
Could you have moved the lever on top of the outlet block during your repairs?

Dave

 

[PaulinBft]

I did move the lever (to clean the dirt off the control valve before replacing the seals on the banjo) and I may have left it in the wrong position. I assume this valve feeds both outlets in the "6" position and only the hitch cylinder in the "5". Otherwise i couldn't have used the loader and the box blade without moving the lever - and I never had to.

I am reasonably sure I tried both the "5" or "6" position after repairs but history has taught me I can't trust my memory so I can't swear it. It's pouring outside now but I'll try moving it when the weather clears a bit.

As for misconnecting lines, the only hoses I could possibly have switched are the implement supply and return lines on this control valve which connect it to the control block for the FEL. Rightly or wrongly, my thinking is that that would just reverse the direction I'd the lever to raise or lower the bucket. (Oh. I checked to make sure those were seated properly too.)

Otherwise, the only changes I have made to the hydraulic system are replacing two hoses to the FEL cylinders - and then one at a time and weeks apart so I couldn't have gotten those wrong.

 

[North Idaho Wolfman]

Here is one major inherent issue with that type of system (2 Hose), there is no pressure relief before the rear of the tractor so any issue before it dead heads the pump.
Turn the valve to bypass the loader valve and see if your problems disappear.
If everything does go back to normal (besides the loader), then you have an issue with a hose connection (could be a quick disconnect not seated properly) or it could be another issue with the valve.

 

[PaulinBft]

Does this not act as pressure relief or bypass in the hitch controller? (not that I've seen a flow diagram for it)

KubotaPad

kpad.kubota.com

 

[North Idaho Wolfman]

Does this not act as pressure relief or bypass in the hitch controller? (not that I've seen a flow diagram for it)

KubotaPad

kpad.kubota.com

View attachment 125567

It does, but only for the three point as you've added the loader to be before the pressure relief.
Hard to relieve pressure when the pressure never gets to the relief valve.
When you add in the loader valve without a tank line, there is no place for over pressure to go.

 

[TheOldHokie]

It does, but only for the three point as you've added the loader to be before the pressure relief.
Hard to relieve pressure when the pressure never gets to the relief valve.
When you add in the loader valve without a tank line, there is no place for over pressure to go.

Not quite. The B6200 has a main pressure relief built into the hydraulic outlet block which prevents over pressuring the pump.

The two line valve has an IN and TANK port. He is using TANK for power beyond. Poor choice but that setup still relieves out the TANK line which works just fine. for limiting inlet pressure on the valve as long as the down stream valve (3pt) is open to tank. In the event the tank line is blocked the pressure relief in the outlet block protects the entire circuit.

Dan

 

[North Idaho Wolfman]

Not quite. The B6200 has a main pressure relief built into the hydraulic outlet block which prevents over pressuring the pump.

The two line valve has an IN and TANK port. He is using TANK for power beyond. Poor choice but that setup still relieves out the TANK line which works just fine. for limiting inlet pressure on the valve as long as the down stream valve (3pt) is open to tank. In the event the tank line is blocked the pressure relief in the outlet block protects the entire circuit.

Dan

Yes you are right.
I don't know which model I was thinking of that has the block but no pressure relief.

 

[Dave_eng]

I did move the lever (to clean the dirt off the control valve before replacing the seals on the banjo) and I may have left it in the wrong position. I assume this valve feeds both outlets in the "6" position and only the hitch cylinder in the "5". Otherwise i couldn't have used the loader and the box blade without moving the lever - and I never had to.

I am reasonably sure I tried both the "5" or "6" position after repairs but history has taught me I can't trust my memory so I can't swear it. It's pouring outside now but I'll try moving it when the weather clears a bit.

As for misconnecting lines, the only hoses I could possibly have switched are the implement supply and return lines on this control valve which connect it to the control block for the FEL. Rightly or wrongly, my thinking is that that would just reverse the direction I'd the lever to raise or lower the bucket. (Oh. I checked to make sure those were seated properly too.)

Otherwise, the only changes I have made to the hydraulic system are replacing two hoses to the FEL cylinders - and then one at a time and weeks apart so I couldn't have gotten those wrong.

View attachment 125563

In this photo the outlet block lever is cutting flow to the loader.
Dave

 

[TheOldHokie]

In this photo the outlet block lever is cutting flow to the loader.
Dave

Yes and that turns the loader "off".

With the loader's PB hose still connected it also back pressures the tank port on the valve when the 3pt is operated same as when the selector is in the "loader" position.

Dan

 

[TheOldHokie]

I did move the lever (to clean the dirt off the control valve before replacing the seals on the banjo) and I may have left it in the wrong position. I assume this valve feeds both outlets in the "6" position and only the hitch cylinder in the "5". Otherwise i couldn't have used the loader and the box blade without moving the lever - and I never had to.

I am reasonably sure I tried both the "5" or "6" position after repairs but history has taught me I can't trust my memory so I can't swear it. It's pouring outside now but I'll try moving it when the weather clears a bit.

As for misconnecting lines, the only hoses I could possibly have switched are the implement supply and return lines on this control valve which connect it to the control block for the FEL. Rightly or wrongly, my thinking is that that would just reverse the direction I'd the lever to raise or lower the bucket. (Oh. I checked to make sure those were seated properly too.)

Otherwise, the only changes I have made to the hydraulic system are replacing two hoses to the FEL cylinders - and then one at a time and weeks apart so I couldn't have gotten those wrong.

View attachment 125563

Reversing the supply and return will not reverse cylinder direction. It reverses flow through the neutral circuit in the valve and can cause all sorts of problems. I would suggest you reconfigure the couplers on the outlet block so that they are one male and one female to prevent accidental reversal of IN and OUT.

Here is how the hydraulic outlet block on the B6200 tractor works. I will also suggest you consider converting what you have to the proper power beyond type loader valve and plumbing.

Dan