L 3400 jumpy 3PH

[kubby 2013]

Has there ever been a solution found for the jumpy 3PH problem on the L 3400 tractors? Mine seems to be even worse than it was. Maybe it just me.

 

[North Idaho Wolfman]

The 100% solution is to get a valve for a grand L.

Other than that, there has been minor successes noted in adjustment of the feed back and changing fluid and filters.

 

[kubby 2013]

The 100% solution is to get a valve for a grand L.

Other than that, there has been minor successes noted in adjustment of the feed back and changing fluid and filters.

Where does the valve go and what is the part number?

 

[CaveCreekRay]

The L-Series Kubotas suffer from a series of bad 3pt valves. Mine was so bad, the rear of the tractor almost jumped off the ground.

The good news: The valve is easy to get to. Its located on the top cover to your rear end, located right under your seat... Here the cover is off and upside down on the bench. The valve is on the right end...

Here is a close-up of the L-3800 valve, likely the same on in your machine now...

Here is what is under that rear-end cover...

Now, the bad news.. The valve alone is $970. That is what my L-3800 valve ran (under warranty). Getting that valve installed correctly to make sure its adjusted right requires a shop manual and a boatload of patience. Clearly, the shop manual for your L-3400 is not going to give you details and measurements for substituting a Grand valve. Are they the same? Only someone who installed on can tell you. Getting it installed is easy. Getting it adjusted is a lot harder...

 

[kubby 2013]

The L-Series Kubotas suffer from a series of bad 3pt valves. Mine was so bad, the rear of the tractor almost jumped off the ground.

The good news: The valve is easy to get to. Its located on the top cover to your rear end, located right under your seat... Here the cover is off and upside down on the bench. The valve is on the right end...

Here is a close-up of the L-3800 valve, likely the same on in your machine now...

Here is what is under that rear-end cover...

Now, the bad news.. The valve alone is $970. That is what my L-3800 valve ran (under warranty). Getting that valve installed correctly to make sure its adjusted right requires a shop manual and a boatload of patience. Clearly, the shop manual for your L-3400 is not going to give you details and measurements for substituting a Grand valve. Are they the same? Only someone who installed on can tell you. Getting it installed is easy. Getting it adjusted is a lot harder...

So is it a matter of making some precision measurements or something else? I am a retired machinist so I have no problem with doing some precision measurements. From what I have seen at the dealers if they can do it a trained chimpanzee could.

 

[CaveCreekRay]

Sounds like you won't have any problems.

The good news is, you can put the lid back on with a couple bolts, try the 3pt and pop the lid off in a minute or two to get the adjustments done correctly. There is no gasket for the lid and my tech sealed mine with a grey silicone gasket material.

Might be worth a case of your Kubota MX techs favorite adult beverage to get the adjustment specs for that swap. If you have local guys to ask, see what their suggestion is. And Messicks might have the part cheaper. Ask you local part guy if he'll match Messicks.

For the record, Kubota put a "new and supposedly improved" valve in mine. It "workie super-extra-goody" for over two years. At least my tractor doesn't look like I am trying to bounce like a low-rider. If they suggest the same valve for your machine, all you have to do is measure whatcha got and put it back together the same way.

 

[kubby 2013]

Thank you for the info. At least there is a solution available. Too bad they didn't issue a recall as this is a total disaster. That is the only fault I have with it. Have a 1990 L2850 that I bought new and it is a lot better built than the newer ones .IMO

 

[CaveCreekRay]

You are very welcome.

The 3pt control valve is actually a pretty simple device. Based upon the position of the 3pt control lever, this valve either ports fluid to the 3pt piston to move the 3pt arms up, or bypasses pressure to let the let the pressure to the piston down. As you move the lever to raise and lower the 3pt, this valve is chasing the lever, trying to resolve it back to neutral pressure, That is why the adjustment has to be so precise.

Other than that, you can see the valve is only held in with two bolts. Pretty simple swap. And getting the rear end cover off is pretty easy. Just be sure to have an old T-shirt handy to cover up the rear ends gaping hole. They always tend to gobble up loose things!

By the way, if you do a swap on your valve, a write-up here would be very helpful. I did one of the warranty work with photos stored off site and the off site storage blocked access after they changed their business model. That thread is now missing all of the pictures and videos I included with it. Storing pictures on the site is fairly easy, once you get the process down.

Ray

 

[kubby 2013]

So is the pics the new valve or the old one? and what is the difference visually?

 

[wendol]

The L-Series Kubotas suffer from a series of bad 3pt valves. Mine was so bad, the rear of the tractor almost jumped off the ground.

The good news: The valve is easy to get to. Its located on the top cover to your rear end, located right under your seat... Here the cover is off and upside down on the bench. The valve is on the right end...

Here is a close-up of the L-3800 valve, likely the same on in your machine now...

Here is what is under that rear-end cover...

Now, the bad news.. The valve alone is $970. That is what my L-3800 valve ran (under warranty). Getting that valve installed correctly to make sure its adjusted right requires a shop manual and a boatload of patience. Clearly, the shop manual for your L-3400 is not going to give you details and measurements for substituting a Grand valve. Are they the same? Only someone who installed on can tell you. Getting it installed is easy. Getting it adjusted is a lot harder...

Would you by chance have the part number for the Grand L valve?
I would really like to get this changed out on my L3800.

 

[CaveCreekRay]

Sorry guys. The pics were shot at my dealer shop under warranty service. The valve you see was the new valve after installation. It was the "improved" L valve and I believe it had the exact same part number as the old part. You can see the number in the pics...

The Grand is a heftier machine and I think it has a Class 2 3pt. I have heard the valve can be installed in the L class but, I have no details on part number or installation details. Hydraulics being half magic anyway, I am guessing the Grand just has a slightly larger 3pt piston. The L's is huge already (see pic below)

If you guys uncover any, please share them with the Orange crowd.

I asked my service tech about it at the time and he said that "o-fish-ully" Kubota had no information about the swap. Being warranty service, he had to work inside of their rules. That meant a part for part swap with L-parts.

The piston is big on an L... about 4" in diameter!

 

[wendol]

The 100% solution is to get a valve for a grand L.

Other than that, there has been minor successes noted in adjustment of the feed back and changing fluid and filters.

Wolfman, can you provide more info as to Grand L part number, Grand L model number, and any addition details or sources on this "fix"?

Thanks!!!