Rear hydraulic on Kubotas the less expensive way

BBELL · Nov 8, 2003

All you guys that don't want to pay $600,$800, up to $1400 for rear hydraulics. On the rear housing of your tractor(on the newer ones anyway) under the seat, you'll see a cast cover with three bolts in it(if sitting on tractor it would be on the right) , maybe three inches by three inches. Thats a blank, take it off and you'll see on the back side of this blank two port holes( one inlet and one outlet. Take this piece to your local backyard machinist, get him to build one of these( can be made out of a block of steal 2 5/8" x 2 5/8", 3/4' thick. Drill your port hole thru the block, same as the three mounting holes. I tig welded two peices of 1/2 O.D. pipe two the two port holes with a JIC fitting on the other end of 1/2 inch pipe to accept a hydraulic hose (female JIC swivle). Run those two hoses to a valve bank( the valve spool has to be a open center system.) I built my at work on a drill press, made the o-ring grooves with a broch drill bit. OK the cost the block was free for me. Thank you, my employer, lol. The valve bank( a three spool) out of Prince Hydraulic $150.00, hyraulic hoses $100 more, quick dissconnect $20 to $30 more and your in bussiness. Any Question email me.

Junkman · Nov 8, 2003

Re: Rear hydraulic on Kubotas the less expansive way

Thanks for the information. What model tractor do you have? Now I know why those Navy destroyers cost so much!!!!! LOL...... /forums/images/graemlins/grin.gif

oops...... guess that I didn't scroll down far enough.... now I know that you have a L-4310.... must have been one of my many senior moments.....

40Kchicks · Nov 8, 2003

Re: Rear hydraulic on Kubotas the less expansive way

Good job Bruce,

Welcome aboard. I always like reading about ideas to do something with less expense. I have a friend wanting to do a TNT on his 3710. I'll have to pass on the info. Keep it up.

My remotes on my M9000 cost $750. One comes standard and the second was put into the price of the tractor when I bought it.

Eric

MadReferee · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

On the B2410/2710/2910 Kubota makes the outlet block. It cost only about $69.

What you are really paying for is the over priced spool valves.

Beware that not all models have the aux hydraulic outlet. The L series do, the above mentioned B series do, the B7500/7800 DO NOT. I am not sure about the BX series.

art · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

One thing to take into consideration here, when doing things to a tractor make sure that it does look as close to factory original as possible for resale. Often we have people wanting us to take there tractors in trade and they have numorous add ons that improved the tractor for them but they lower the value for the next owner. Make sure they are easily removable with no scars left or they blend in to the tractors lines and functions. Most all makes can be improved and often cheaper just as you have found here, keep in mind all other functions of service.

5030 · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

BBELL:

Seeing as I have my own machine shop, I need to clarify, correct you on some points.

The replacement block cover must be flat. Not stock flat, but ground flat and parallel. That takes a surface grinder which most home shops don't have. The port holes must align exactly with the corresponding holes in the tractor itself. The "O" ring grooves you made were not machined with a "broach" drill, there is no such thing. You used a counter bore. And lastly, You are very lucky that when you Tigged the pipes to the block, you got a fluid tight weld without Magnafluxing the welds. The inherent pressure developed (in the excess of 2100 psi) will compromise even the most slightly porous weld.

Most, as you say, "backyard" machinists don't have the equipment or the expertise to make the part. Besides, the liability for failure is high.

Any leak in the block or the welds could cause injection of hydraulic fluid into your body if you were to get close to the block or pipes if they leaked. Fluid injection into your epidermis results in amputation of the affected extremity (fingers, hand, arm, etc.). Besides, a high pressure leak will deplete the tractor of fluid in a short time, possibly destroying the transmission.

That is the reason why the block costs what it does. Kubota static tests each one.

I agree that the Kubota spool valves are pretty pricey. I have 3 sets on my 5030. One thing about the Kubota valves is that they come with all the necessary bracketing and hose routing that makes the installation look right and function flawlessly. The Kubota spool valve sets mount "close coupled" to the block, with the couplers in a convenient spot.

JerryG · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

Daryl,
Gee Whiz Jump down the guys throat. Its know wonder that we have less folks showing mods now than we did only a couple of years ago.
BTW You don't have to surface grind a surface that is not a sealing surface with no contact, the only sealing contact is the counter bored o-rings.

JerryG · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

BBell,
Thanks for sharing. I agree that the companies charge a whole lot more for the valves than they should. The price they charge is totally obscene.
The main thing when engineering mods like this, make sure that the correct lines are hooked up to the right place on the tractor and that the welds are really good. It appears that you have done these things. This was only for other that might try to do the same thing.
Art, is right. You at least need to make it look factory if you plan to leave it on at resale time. It it looks cobbled up, no one wants to buy it. Unless it is removed before resale.

Bird · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

( Gee Whiz Jump down the guys throat )

Jerry, I don't see it as anyone jumping down anyone else's throat. /forums/images/graemlins/confused.gif Sounds to me like BBELL had a pretty good idea that worked well for him and might, or might not, work well for others. Now we have to assume that BBELL knew what he was doing and did it right, but Art and Daryl then pointed out some possible pitfalls for others who might try it and not know about them.

( Its know wonder that we have less folks showing mods now than we did only a couple of years ago. )

If I should post a message showing modifications I made, I would hope for responses that might cover something I overlooked (I might learn something that would help in the future) and I would certainly hate to have someone try to copy what I had done and get hurt by it; either physically or financially.

So I would hope the possibliity of criticism of a modification would never stop others from showing theirs.

JerryG · Nov 9, 2003

Re: Rear hydraulic on Kubotas the less expansive way

Bird,
That was not what it was. It was as though he was nit picking everything that BBell had to say. It was as though he was looking down his nose at him. You can't talk to a new member like that and expect them to stay with us. Pointing out safety items is one thing. This was an other.