Kubota Loader Detent Kit - Help!

[srr5008]

I was having some problems with my Kubota L2900 (LA480 Loader) where it wouldn't stop going up and then it didn't want to go down at all. Also, the float didn't work. I took apart the bottom of the control valve to take a look at the ball detent assembly. I found that the small spring (which pushes the detent balls outwards for the float position) was kinked pretty good, so I figured it would be a good time to order a ball detent kit and rebuild it (items "A" on the diagram below)



I took everything apart, which was easy enough. Putting things together seemed to go smoothly as well, until I tried to operate the loader. For some reason, the joystick is extremely stiff. For example, when I lift the bucket not only is there resistance in the joystick, but the bucket keeps right on going up - it's almost like the large return spring that came with the detent kit isn't stiff enough to return the joystick to a neutral position. When I lower the bucket (and I really have to force the joystick) the same thing happens, the bucket keeps on going down on its own (note that this is not float - the float position still doesn't appear to be working). I noticed when I took the assembly apart for the first time, that the uppermost o-ring had been sucked inside the valve assembly and was wrapped around the spool further up that it was supposed to be. I fixed this, and still had the same issues with the joystick. I did notice that when I take the bottom of the control valve off (exposing the bottom of the spool and the detents) that I lose most of the resistance in the joystick. I still don't think it's returning to neutral like it should (again maybe due to a weak spring?).

Any idea guys? I've had this darn thing apart over a dozen times and I am drawing blanks. If helpful, there are some good pictures of the same spool assembly I have at the bottom of the following thread: http://www.tractorbynet.com/forums/kubota-owning-operating/143142-la680-spool-valve-leak-spewing.html

My next step will be to put the old guts back into operation (but keep the new smaller spring for the detents) to see if that fixes the issue. But I won't have time to look at it until this weekend so I wanted to see if anyone had any ideas in the meantime.

Thanks,

Steve

 

[/pine]

...I noticed when I took the assembly apart for the first time, that the uppermost o-ring had been sucked inside the valve assembly and was wrapped around the spool further up that it was supposed to be....

This speaks volumes...was the nut/bolt on the bottom of the spool tight the very first time you took the cap off the bottom?

 

[srr5008]

Yes everything was extemely tight.

 

[Leejohn]

Where are you putting big ball? Above or below the 3 small ones?

 

[srr5008]

Where are you putting big ball? Above or below the 3 small ones?

Based on what i saw online and following the order that parts were in when i disassembled, the top to bottom order is as follows: spool, 4 small detent balls, spring (which seems to pass betwen/behind the detent balls) then the large ball, then the cap

 

[Leejohn]

Well my guess was spool, spring, large ball, 4 small balls, then the sleeve. After that would come the cover, disk, then the snap ring. I have not had mine apart, but it would seem to me the small balls need pressure on them all the time until it is put in float.

 

[srr5008]

Thinking that over, that makes sense to me. I couldn't for the life of me figure out how the float was supposed to be engaged with the configuration I witnessed. I thought maybe the previous over had messed something up (I've found several "interesting" repairs) but the exploded diagram (which is very unclear) appeared to back up the original configuration. I'll have to give that sequence a try.

 

[srr5008]

Well my guess was spool, spring, large ball, 4 small balls, then the sleeve. After that would come the cover, disk, then the snap ring. I have not had mine apart, but it would seem to me the small balls need pressure on them all the time until it is put in float.

Upon further thought, and contrary to my comment above, I don't think that could work. The large ball has to be under the 4 small detent balls, or the detents would fall out the bottom. When the joystick is in a neutral position, the smaller detents get pushed inwards (towards the inside of the spool) and the small detent spring keeps them from falling out of place. When the joystick is pushed forward, the spool/dentents are pushed downwards, the small detent spring compresses, which brings the large ball into contact with the bottom of the detents, pushing them outwards to catch the lip in the cap and engage the float position.

For some reason I have resistance on the joystick and I can't get it to click into the float position.

 

[Leejohn]

I'll check tomorrow and see what way the spool is moved when going into float. Can the sleeve that goes over the balls be put on either way. (end for end)?

 

[srr5008]

I'll check tomorrow and see what way the spool is moved when going into float. Can the sleeve that goes over the balls be put on either way. (end for end)?

The sleeve is theaded on one end only, so it only goes on one way.