Hydraulic Issue

[Kubotadad]

I inherited a Kubota B1550 and know absolutely nothing about tractors. The current issue I am experiencing is with the front loader lowering. Raising and tilt work absolutely fine, but it takes forever to lower down...absolutely no pressure at all.

HELP!

 

[TheOldHokie]

I inherited a Kubota B1550 and know absolutely nothing about tractors. The current issue I am experiencing is with the front loader lowering. Raising and tilt work absolutely fine, but it takes forever to lower down...absolutely no pressure at all.

HELP!

Whats the make and model of the loader?
Tilt works in both directions or just one?
Will the loader lift the front wheels off the ground?

Dan

 

[Kubotadad]

Whats the make and model of the loader?
Tilt works in both directions or just one?
Will the loader lift the front wheels off the ground?

Dan

Thanks for the reply!
Loader is 1640A
Tilt works fine in both directions
No...not enough pressure to lift front tires off ground.

 

[TheOldHokie]

I inherited a Kubota B1550 and know absolutely nothing about tractors. The current issue I am experiencing is with the front loader lowering. Raising and tilt work absolutely fine, but it takes forever to lower down...absolutely no pressure at all.

HELP!

Are you sure you have the bucket and lift hoses connected to the correct ports on the valve? Sounds like you might have bucket and boom reversed.

Dan

 

[Kubotadad]

Are you sure you have the bucket and lift hoses connected to the correct ports on the valve?

Dan

Should be correct! It was working just fine for the last year and I have never disconnected the hoses.

 

[TheOldHokie]

Should be correct! It was working just fine for the last year and I have never disconnected the hoses.

So this problem just suddenly popped up out if nowhere?

Dan

 

[Kubotadad]

So this problem just suddenly popped up out if nowhere?

Dan

Yes...in a sense...the loader initially started to creep up without warning. That went away and now the loader does not lower.

 

[TheOldHokie]

Yes...in a sense...the loader initially started to creep up without warning. That went away and now the loader does not lower.

Creeping up is uncommon. Have you checked and laid eyeballs on the operation of the boom spool?

Dan

 

[Kubotadad]

Creeping up is uncommon. Have you checked and laid eyeballs on the operation of the boom spool?

Dan

Dan...you just went too deep for my knowledge base...lol. I have no idea what that is or how to lay eyeballs on it.

 

[TheOldHokie]

Dan...you just went too deep for my knowledge base...lol. I have no idea what that is or how to lay eyeballs on it.

No proplem. Post a good picture or two of the loader control valve and joystick control lever.

Dan

 

[Kubotadad]

No proplem. Post a good picture or two of the loader control valve and joystick control lever.

Dan

 

[TheOldHokie]

View attachment 169500 View attachment 169501 View attachment 169502 View attachment 169503

Dont see anything obvious in the (excellent) pictures.

Do you see the two rods that come out of the valve body? Those are the "spools" that control hydraulic flow.

Move the joystick handle back and forth from raise to lower several times while watching the leftmost spool. It should slide in and out of the casting and stop in the mid point when you let go of ths handle.

Now compare that movement to the movement of the right spool when you move the joystick back and forth between dump and curl. Both spools should move the same (more or less) amount and automagically center when you release the levef.

Dan

 

[Russell King]

You might want to check that the three point control lever is in the fully down position.

That effects the FEL in some cases since it can be releasing pressure from the system.

 

[North Idaho Wolfman]

You might want to check that the three point control lever is in the fully down position.

That effects the FEL in some cases since it can be releasing pressure from the system.

Well sort of,
Just not in the full up position
Because if the three point feedback is not adjusted properly it will put the hydraulic system into relief.

 

[North Idaho Wolfman]

View attachment 169500 View attachment 169501 View attachment 169502 View attachment 169503

Start witth the simple stuff.
Disconnect and reconnect any of these quick disconnects.
There should be three for the loader.

 

[TheOldHokie]

More precisely when for any reason the 3pt valve does not center it blocks the neutral circuit. Since most Kubita valves have serial spools on the boom that blocks the return flow from the lift cylinders preventing the boom from going up or down. That does not appear to be the case here.

 

[TheOldHokie]

The OP reported early on that the problem started with the boom spontaneously lifting.

Now, for the analytically inclined - what can cause that?

AFAIK not a bad coupler or a neutral circuit problem.

AFAIK that could only happen if the spool is shifted out of neutral or does not return to neutral. That might also be related to a problem getting the loader tobraise.

Hence my initial focus on the joystick linkage.......

Dan

 

[North Idaho Wolfman]

The OP reported early on that the problem started with the boom spontaneously lifting.

Now, for the analytically inclined - what can cause that?

AFAIK not a bad coupler or a neutral circuit problem.

AFAIK that could only happen if the spool is shifted out of neutral or does not return to neutral. That might also be related to a problem getting the loader tobraise.

Hence my initial focus on the joystick linkage.......

Dan

Or the detent section.

 

[TheOldHokie]

Or the detent section.

Yes - all diagnosed by simply observing the spool movement.

Dan