Diverter valve mystery

[M105X]

I mentioned a few days ago I was putting a diverter valve on my M105X. I got all the hoses hooked up yesterday and put the grapple on today to try it out.

Everything worked great except for when I diverted the oil to my grapple. The grapple opened and closed but in the opposite direction I wanted to move the lever. I figure no problem just switch the grapple hoses and it will change it to the direction I want. Wrong!! The grapple would only move in one direction no matter what way I move the lever. (move to left and it closed, move to right and it closed) Switched hoses back and it worked but not in the direction I wanted it to.

I then switched the 2 input hoses from the loader spool thinking it would solve my problem with the grapple and I would have to change the hoses on the bucket tilt to get them back to normal. Wrong!! The grapple and bucket would only go in one direction no matter what way I moved the lever.

So I call Fasse since I know it is a Fasse Valve. They tell me that since I have a Kubota take it off the dump circuit and put it on the up and down circuit. I did that and it works perfect. The guy told me he has had this happen with Kubota's before and Kubota are having some trouble with the factory dump circuit valves doing goofy things especially when a diverter is involved.

Any ideas of why this would happen? I would like to move it back to the dump circuit.

Could it be the relief valve in the dump circuit? I think my relief valve in my dump circuit may be set to light. On my previous tractor I could set the loader on the ground flat and move lever to dump and roll the front end of the tractor off the ground and the bucket up on the cutting edge. This tractor tries but just bypasses oil. If I tilt the bucket and put pressure on the ground and try to dump it more it goes in reverse and flattens the bucket out.

Thanks

Tom

 

[MadReferee]

I don't think your dump spool's work ports have their own relief valve. You normally see that on heavy equipment valves.

Sounds like you loader valve is a 3-way valve instead of a 4-way valve. Take a look at THIS post to get an explanation.

 

[rbargeron]

Tom, on many Kubota loader valves the dump circuit has a regenerative loop that routes the flow from the exhaust side directly back to the pressure side. This speeds up the dump function. The bucket weight plays a part in the flow balancing, which may explain why the grapple doesn't work correctly on the dump circuit. The poor downforce you describe points to the regenerative feature being out of tune somehow. My books don't say how to check or adjust it. Maybe someone else knows more details.

 

[MadReferee]

My books don't say how to check or adjust it. Maybe someone else knows more details.

There is no adjustment as it is a function of the internal spool design. There could be a broken spring or something else broken inside the spool. If this is the case then disassembly is the only way to tell for sure.

 

[Berniep]

There is nothing wrong with your valve. I ran into exactly this problem when putting on my grapple with diverter. As others have said it's the regenerative circuit. I just run it with the grapple going the opposite way I wanted and just got used to it. After a few hours of use it's natural.
You may have to go past the normal dump position to get full pressure to the uncurl position.. It's like the float position on the loader arms.
I don't like it this way, I think it should go into regen mode if you go all the way past the detent instead of before it, but the engineers evidently don't think the way I do. (btw I didn't know about the detent untill I read it here on tbn, it's a pretty stiff detent on mine and the manual doesn't mention it)