loader creeps up when 3pt is lifting

[massey990]

Hi, hope someone can help
I'm trying to help a neighbor with a problem with their tractor.
I think it is a B21 or B2100 with a LA 301 loader. Recently the bucket has started creeping up when ever the 3 point hitch is moved.

I inspected the spool for debris etc. (after reading topical posts) no joy, the bucket still goes up on it's own.

Any ideas?

 

[J_J]

When you are using the 3pt, the FEL valve is also pressurized. If the FEL valve lever is not in neutral, you might send fluid into the FEL lift cyl.

Might also check the FEL load check valve for debris. I believe it also prevents any back pressure.

 

[massey990]

Thanks for the reply.
This is something that assumably just started?

 

[Jay4200]

Hi, hope someone can help
I'm trying to help a neighbor with a problem with their tractor.
I think it is a B21 or B2100 with a LA 301 loader. Recently the bucket has started creeping up when ever the 3 point hitch is moved.

I inspected the spool for debris etc. (after reading topical posts) no joy, the bucket still goes up on it's own.

Any ideas?

The FEL valve has to be engaged. If the FEL lever is hanging down and engaging the lift cylinders, 3pt movement would cause the FEL to raise. Mine does that sometimes. Perhaps there is some damage to the FAL valve causing a bypass into the lift cylinder?

JayC

 

[massey990]

The joystick seems to fine, not engaging. The loader had not been being used very much when the problem started.

 

[massey990]

All these folks with tractors and nobody has any other sugestion on what the problem may be or advice to offer?
should I just recommend replacing the valve? dealer cost is an absurd $1,050.00, Surplus Center has them for less than $250.00

comments?, advice?
Thanks

 

[Farmerford]

It seems almost certain that the spool is slightly off center; so slight that the normal pressure of fluid flowing through the body does not force fluid through the work ports. Confirm this by holding light pressure on the valve handle in the boom down direction and liftilng the three point with a heavy load. If that fixes the problem, it confirms that the problem is the spool position when supposedly in neutral.

You said the handle is not pressing the spool and there is no foreign material in the valve body, so you must have taken it apart. That leaves only one thing, the spring centering mechanism at the bottom end of the valve is not holding the spool centered. It is hard to imagine how that could have failed, but perhaps it did. A broken spring? But you would have seen that when taking the valve apart. I would try a shim washer under the spring to recenter the spool.

 

[massey990]

It seems almost certain that the spool is slightly off center; so slight that the normal pressure of fluid flowing through the body does not force fluid through the work ports. Confirm this by holding light pressure on the valve handle in the boom down direction and liftilng the three point with a heavy load. If that fixes the problem, it confirms that the problem is the spool position when supposedly in neutral.

You said the handle is not pressing the spool and there is no foreign material in the valve body, so you must have taken it apart. That leaves only one thing, the spring centering mechanism at the bottom end of the valve is not holding the spool centered. It is hard to imagine how that could have failed, but perhaps it did. A broken spring? But you would have seen that when taking the valve apart. I would try a shim washer under the spring to recenter the spool.

Thanks for the advice and suggestion I will give it a try.
The float detent seems to be worn out so the spring may be weak also.

 

[J_J]

Here is a 10 GPM loader valve, with float and PB if needed. .

Surplus Center - 2 SPOOL COMPACT 10 GPM JOYSTICK CONTROL VALVE

 

[massey990]

That is one I had forwarded to the owner for consideration, it also include a float detent. The other one has no joystick just two levers, both about the same price.

Thanks