FEL control valve problem

[TimBuck2]

I have a Kubota L4310 HST with a FEL. When I plowed this past Sunday I had a problem with the loader valve.

The boom won't raise when the lever is pulled all the way back; if I pull the lever past about 3/4 of its throw the boom stops at what ever height it is at.

I can raise the boom slowly (up to about 2/3's speed) but as I pull back further on the valve, once I hit a certain point, the boom stops. At the point where the boom first stops, there is pressure to the cylinders (slight lag in the engine, and the hoses to the cylinder jump and straighten out), but if I pull all the way back, the pressure is released to the extent that the hoses slacken and no lagging of the engine. The boom does not fall.

All other hydraulic functions for the FEL and the hydrostatic drive work as they should, and the loader appears to have normal power for lifting.

The 3-pt hitch (power beyond from the FEL valve) seems to work as it should (raises very slowly when the FEL valve is in that stopped - pressure position described above, but raises at normal speed when the FEL valve is pulled all the way back).

This is a HUSCO FEL valve. The tag has fallen off, but I believe it is a 9210 series valve. Not sure if it helps in diagnosis but ...., the bucket dipper cylinders still operate when the boom valve is in the float position.

Lastly, Sunday was in the mid- to upper 30's, relatively warm and sunny when I plowed, so I don't believe this is a freeze problem.

Thanks for any ideas how to approach this.

 

[TimBuck2]

Another thought that might jog some ideas about how to approach this problem and a fix:

Because there seems to be pressure build up in the hoses to the piston side of the boom cylinders (i.e., to extent the rods) just at the point that they stop moving, I am thinking that the problem may be a blockage that keeps the fluid from exiting the rod side (i.e., to retract the rod) of the cylinders.

However, I can't picture how this would happen at higher flow rates and not lower flow rates.

 

[/pine]

just an off the wall suggestion...
Remove the caps on the bottom of the boom spool and make sure the bolt holding the spring in place is tight...also check the bolts holding the joystick's articulated bearing joints are tight...

 

[J_J]

Does the valve lever snap back to neutral or center?

You might look in the can on the bottom of the valve for broken springs.

Is it cold enough for ice to form in the cans due to water?

 

[TimBuck2]

The springs or bolts for the joy stick are good suggestions: the joy stick seems to snap to neutral as it should, however (I forgot to mention) the valve jumps out of the float dentent easier than it did before when plowing on rough ground.

I will look into those things this weekend, thank you.

 

[J_J]

If your lever jumps out of float, you need to remove the cans on the bottom of the valve and inspect the
ball bearings and the groove for rust and debris.

Then clean or replace bad parts and then lube good and replace the can with weep hole down so moisture can drain .

 

[Egon]

Pull the cover off the control valve linkages and check for wear or sticking linkages and just general sloppiness. If there are cables make sure they move freely.

 

[TobyH]

TimBuck2, did you ever solve your problem? My BX2200 with an LA211 loader with 4-way Husco valve has been doing the exact same thing. I've pulled the valve completely apart a couple times now with no improvement in function. All functions work fine except raising the loader. I pull back and the loader raises until I pull back beyond 2/3 of the way and the loader stops. Anyone else out there have a solution? Thanks.

 

[TimBuck2]

Toby,

I bought a re-build kit for the side of the valve that controls the FEL boom. The float detent assembly was worn, and perhaps some other components. Apparently, the wear allowed the throw of the spool to extend beyond where it was supposed to.

The re-build kit is rather pricey for about 2 oz. of parts (about $135 as I recall) but it did the trick. I also tried to find rebuild kit that was not labeled Kubota hoping to save some money, but had not luck.

Good luck.

 

[TobyH]

Thank you! I'll check with the dealer on that when I go to pick up the $36 5" hose I ordered. Guess it beats the cost of a new valve...at least that's how they want you to feel.