third function value help with Kubota

[cattlefarmboy]

I have a Kubota 5140 with a third function value installed by the dealer and a Dirt-dog grapple. When using the grapple, it can be open and the tractor is off then the grapple will start to close on it self. It the same if you are using it with a load and it will start to back off. I have talk with dealers and techs about it and they all have passed it off with being normal. I know that is not right cause you wont have a trackhoe thumb start losing a load on the job site. What could be the problem with the value or hydraulics. It not the grapple seals leaking, i talk with a company tech to check the seals by disconnect the hydraulic and try to move it back and forth. Could it be trash in the value? I'm just tried of bumping the button all the time.
Thanks, James

 

[J_J]

To check the valve, open the grapple and shut the engine off.

Since the cyl is supposed to be locked with the valve in neutral, the grapple should not move.

Remove the IN hose and the OUT hose from the 3rd function. If the grapple falls/closes, then you will see fluid flowing from either port that means that the valve spools are leaking.

If the grapples falls and no fluid flows out the valve, then the cyl piston seals are leaking.

You might also inspect and clean the valve relief.

You could also switch hoses from the curl/lift to the grapple to see if the grapple will hold.

 

[bandaidmd]

Your third function is an electrically controlled splitter ?

The curl and dump hold position like they should if not using the "button" ?

My third function is a electrically controlled diverter valve plumbed to the curl to close the lid and once pressure is applied to the lid it holds until i press the toggle switch and move the lever to open it.

 

[beemerphile]

My M5040 has a Dirt Dog grapple and a Kubota OEM 3rd function valve. Mine does the same thing. It leaks down even with the machine running. It is a hassle and I would be interested as well in a cure. I just had the valve off the tractor for other reasons. Mine is a double solenoid electric valve and comes ahead of the loader in hydraulic power sequence. It has a power on/off switch and momentary raise and lower buttons on the loader joystick handle.

I am about to replace the Dirt Dog grapple, so I guess it will answer one question depending on whether the new grapple does it too. I also have a 4-n-1 bucket for the machine but I haven't used it enough to know if it drops like the grapple does.

 

[J_J]

Then your valve or cyl is leaking.

Temporarily switch the lift circuit hose to the grapple and see if the grapple will hold.

Why is your grapple hyd circuit before your loader?

That means that when you are using the grapple, nothing else in the circuit is getting any fluid.

Did the dealer install it that way?

 

[cattlefarmboy]

So it still a problem with it somewhere. It will be this weekend before I can even look into it. I was thinking at one time metal shavings could have gotten in it cause of being brand new.

 

[paulwestski]

Then your valve or cyl is leaking.

Temporarily switch the lift circuit hose to the grapple and see if the grapple will hold.

Why is your grapple hyd circuit before your loader?

That means that when you are using the grapple, nothing else in the circuit is getting any fluid.

Did the dealer install it that way?

That's how the Kubota OEM 3rd function is plumbed, the sub plate has a relief built in.

 

[J_J]

It would seem logical to install the 3rd function valve after the PB on the loader valve.

Then it would not interfere with the loader operation.

Does it work better/not for those that have the valve ahead of the loader?

 

[J_J]

This is a reply from the guys at Messicks.

JJ

I spoke to our service dept...The solenoid for the 3rd function is mounted on a block for the bucket cylinders. It is fed from the loader valve. If your grapple is leaking down, the problem could be in the solenoid valve or internal in the grapple cylinder.

 

[beemerphile]

This is a reply from the guys at Messicks.

JJ

I spoke to our service dept...The solenoid for the 3rd function is mounted on a block for the bucket cylinders. It is fed from the loader valve. If your grapple is leaking down, the problem could be in the solenoid valve or internal in the grapple cylinder.

My 5040 is not, and I imagine the 5140 is the same. I looked in the 1153 loader installation manual and the hydraulic flow is shown exactly as mine is installed... Pump > 3rd Function > Loader valve > rear hydraulics (lift and remotes).