Kubota L3710 Steering Seal Fix?

[Suburban Plowboy]

With help from forum members, I dug into my Kubota L3710 to see why fluid was pouring out. I saw that it shot out from the rear of the steering cylinder when I turned the wheel, so it looks like the seal is gone.

Has anyone here repaired this issue on this model? I can't even see how to get to the cylinder to pull it. Should I give up and call the dealer?

 

[Suburban Plowboy]

I dug up my workshop manual. It says I have to remove the radiator and the bumper. The bumper is connected to the loader, so this may be even less fun than I thought.

I assume these cylinders can be repaired. Is that right? My little John Deere was made with a cylinder that was welded shut at both ends.

 

[BeezFun]

i don't have a manual to look at for your model, but in some situations you can pull the rod end of the cylinder and leave the cap end in place. That can help avoid having to remove the whole cylinder and makes the job easier.

 

[Suburban Plowboy]

I appreciate the replies. Thank you for trying to help.

I sat in front of the computer and researched, and I finally came up with the answers.

The cylinder can be rebuilt, but Kubota does not offer a kit, because that would be intelligent and considerate. You have to sit down with a parts diagram and look at various web sources and make your own list. I will post it here, along with the current prices from Messick's. It comes to a little over $160.

My new question: do I really have to use Kubota seals? Generic seal kits for hydraulics are available for about 20% as much. No one is going to tell me Kubota makes its own seals. I know better than that. And there is no way I'll believe other companies that stay in business selling seal kits are putting out junk year after year. No one would ever go back to them if their products made cylinders fail prematurely.

I'm no engineer, but common sense tells me it should be possible to measure the rod and the piston and find a company that will sell me size-appropriate seals. Otherwise, everyone with an old tractor or backhoe would have to scrap it when the hydraulics leaked.

For other people with the same problem, I will post what I learned while looking for the parts. These parts will work with any tractor that uses the same cylinder. A bunch of Kubota tractors use it. I made a chart, but it probably won't look right on this forum. Sorry about that.

The steering cylinder itself is part TA040-37803, and some places are asking about $1300. That's obscene. It should be closer to $200, based on similar parts for other machines. I would like to support Kubota, but I'm not a charity for giant corporations. If I can get parts cheaper, I will. If I find a source for cheaper aftermarket seals online, I will post the info here.

Maybe some day I'll get ambitious and try to make my own Kubota steering cylinder from a generic.

Diagram MPN Type Needed Each Total

30 TA040-37570 piston gasket 1 16.80 16.80
40 04816-00450 O-ring 1 5.10 5.10
110 08511-02512 bush 2 6.14 12.28
120 04810-50500 O-ring 2 2.92 5.84
120 04817-50500 O-ring 2 4.42 8.84
130 TA040-37560 rod gasket 2 16.80 33.60
140 TA040-37580 seal 2 24.43 48.86
150 TA040-37880 cir-clip 2 17.15 34.30

Total cost: 165.62

EDIT: it looks like you don't have to buy new snap rings (circlips), so remove $34.30 from the cost, leaving a total of $131.32.

 

[BeezFun]

My new question: do I really have to use Kubota seals?

No, take it to any decent hydraulic shop and they'll be able to get the parts. You might want to let the shop do the rebuild, or at least take it to them after you do the rebuild and have them pressure test it. With all the labor involved getting it out, you don't want to put the thing back in and find out it still leaks.

 

[Suburban Plowboy]

Thanks, man. I would love to show some appreciation to Kubota for making a great machine, but sticking it to people like this is not okay. They could sell that cylinder for $300 and sell a seal kit for $100 and still make a big profit.

 

[2manyrocks]

The high price of replacement parts is what keeps independent hydraulic repair shops in business. I had a steering cylinder rebuilt about a year ago. I think it cost about $200.

 

[wdchyd]

“I assume these cylinders can be repaired. Is that right? My little John Deere was made with a cylinder that was welded shut at both ends.”

Yes, assuming your local hyd shop is capable and ambitious

 

[Dave M7040]

Here is the steering cylinder of the WSM.
Unfortunately images leave a lot to be desired.
Dave M7040

 

[Suburban Plowboy]

Here is something weird. I can get Kubota seal kits for big loader cylinders for way less than the parts to rebuild a little steering cylinder.

Example: a seal kit for an LA481 loader cylinder is $44.41 from a dealer.