Announcement

Collapse
No announcement yet.

Kubota conundrum - need a 18 mm 22 tooth spline

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Kubota conundrum - need a 18 mm 22 tooth spline

    I'd like to fit a front end loader to my tiny little Kubota B5100. I need a hydraulic pump drive; the built in pump for the 3 pt hitch is too small for my 2" cylinders on the loader. The front PTO is a 18 mm 22 tooth spline a couple of inches long; all mating parts from Kubota seem to be Not Available, apparently, even though they show in the parts catalogs still . There don't seem to be any adaptors anywhere, either...

    I've got a lathe and mill (but no slotter) w/ a rotary table; I'm loathe to start broaching the spline using the quill on the Bridgeport.

    Would a 18 mm taper lock bushing 'seat in' and transmit the 50 inch-lbs or so I need? This is a two cylinder diesel, so there is a fair amount of speeding up and slowing down... I've thought about just using a section of 5/8" hydraulic hose to connect to the pump drive shaft.

    Any other ideas? I'm all ears.

    - Bart
    Bart Smaalders
    http://smaalders.net/barts

  • #2
    I'd be very tempted to machine a collar that fit snugly over the shaft, and then drill both of them crosswise for a pin or bolt.

    Comment


    • #3
      I'd either talk to a GOOD ag dealer or store, or call up one of the various aftermarket pto shaft manufacturers and ask them to sell you the end you need. Use that to build your adapter.
      "I am, and ever will be, a white-socks, pocket-protector, nerdy engineer -- born under the second law of thermodynamics, steeped in the steam tables, in love with free-body diagrams, transformed by Laplace, and propelled by compressible flow."

      Comment


      • #4
        ".....is too small for my 2" cylinders on the loader."

        What is the 2 inch dimension? Reason I ask, my L35 doesn't have cyl's that large. If it wasn't 6F outside I'd get you a measurement. Or are you "stuck" with existing cyl's.

        Another thing. why does it have splines instead of a fixed mount? I had a couple beers with the local Kubota mechanic after he fixed a valve in the 'hoe. He mentioned that a common repair was that front spline stripping, but mebbe that was only on L35's, didn't clarify.

        Comment


        • #5
          Would shells like this work out?

          "...do you not think you have enough machines?"

          Comment


          • #6
            I can't imagine that Kubota would not be willing to help you.
            They have always seemed to be a responsible company.
            If they won't, I am glad I bought a JD tractor.
            Bill
            I cut it off twice and it's still too short!

            Comment


            • #7
              That tractor had a loader option so the existing pump should have the capacity, or are you trying to fit a loader off of a larger tractor?
              http://www.everythingattachments.com...ecs-s/3902.htm
              Cheers,
              Jon

              Comment


              • #8
                I'd be very tempted to machine a collar that fit snugly over the shaft, and then drill both of them crosswise for a pin or bolt.
                This is definitely on the shortlist. I'd fit a Lovejoy coupling on the collar so I could more easily change the V-belt; the original splined chain coupling sprocket (unavailable) just pulled off for this purpose. There isn't a lot of access to this area; the radiator and v-belts are well shielded from brush, etc.

                I'd either talk to a GOOD ag dealer or store, or call up one of the various aftermarket pto shaft manufacturers and ask them to sell you the end you need. Use that to build your adapter.
                I've looked pretty extensively and spent time on the Kubota forums. This spline is rather unique, apparently. If I had a collar w this splne I'd be done already ; many others have looked for suitable parts as well.

                ".....is too small for my 2" cylinders on the loader."

                What is the 2 inch dimension? Reason I ask, my L35 doesn't have cyl's that large. If it wasn't 6F outside I'd get you a measurement. Or are you "stuck" with existing cyl's.

                Another thing. why does it have splines instead of a fixed mount? I had a couple beers with the local Kubota mechanic after he fixed a valve in the 'hoe. He mentioned that a common repair was that front spline stripping, but mebbe that was only on L35's, didn't clarify.
                The loader was built in the US; this was pretty common in the early years. This was the first generator of Kubota tractors in the US; late 70s to mid 80s, and accessories for these tractors were built in Compton, CA. There were several small tractors of similar size, and a variety of loaders; these were available w/ different subframes to fit them to different tractors. These cylinders are of 2" bore; they were probably easier to source than 1.5" cylinders. The relief valve on the valve assembly is apparently set for around 1000 psi, so yes, they could have used smaller cylinders with a higher relief valve pressure. The advantage of a higher flow pump is that the engine doesn't need to be turning 2500 rpm to make the loader move at a reasonable speed.

                The reason they used splines in the front is that a variety of different accessories could be fitted to these tractors; the loader hydraulics are self-contained as part of the loader. This was not the best design, and later tractors used a larger spline to avoid wear problems.

                Would shells like this work out?

                Something like this could work; I'd need to fit a drive from that.

                I can't imagine that Kubota would not be willing to help you.
                They have always seemed to be a responsible company.
                If they won't, I am glad I bought a JD tractor.
                Well, I have a variety of old equipment from various manufacturers, and parts do become 'no longer available' after a while, esp. for gear that is more than 30 years old. Apparently, parts for these tractors became much harder to get after the 2009 recession.

                That tractor had a loader option so the existing pump should have the capacity, or are you trying to fit a loader off of a larger tractor?
                This loader was originally fitted to a B6100, as far as I can tell. That tractor had a slightly larger engine, but afaict had the same internal hydraulic pump as the B5100.

                I'm going to mull over my options; right now I'm inclined to go w/ the sleeve and roll pin approach as probably the most robust solution.

                Thanks for all of the suggestions!

                - Bart
                Bart Smaalders
                http://smaalders.net/barts

                Comment


                • #9
                  Thank you for the explanation.

                  Comment


                  • #10
                    There is available a "rag style" 18mm steering gearbox coupler that has an internal "double D" config

                    You could probably fit one to the shaft by grinding flats on the existing shaft, but of course that would destroy it for any future spline application.

                    This begs the question, how hard is it to get this spline shaft off of the tractor? And/or how is it attached? If you could turn down the existing shaft to a standard straight fit, or just make an entire new assembly with whatever connection you wanted, that would be the way to go.

                    Dave

                    Comment


                    • #11
                      It's cheesy but I do think a taper lock hub would work.

                      More elegant to wire edm or shape the coupling. Sounds like you could sell excess production.

                      Comment


                      • #12
                        When I needed a a spline coupling for my BX I went to the local dealer and asked for a bent drive shaft and used the coupling end to make my needed drive shaft.

                        Comment


                        • #13
                          Have you tried the Orange Tractor Talks forums?

                          Comment


                          • #14
                            There is available a "rag style" 18mm steering gearbox coupler that has an internal "double D" config

                            You could probably fit one to the shaft by grinding flats on the existing shaft, but of course that would destroy it for any future spline application.

                            This begs the question, how hard is it to get this spline shaft off of the tractor? And/or how is it attached? If you could turn down the existing shaft to a standard straight fit, or just make an entire new assembly with whatever connection you wanted, that would be the way to go.

                            Dave
                            This spline is the end of the engine crankshaft, as unusual as that might be, so I'm pretty much going w/ an adaptor option.

                            It's cheesy but I do think a taper lock hub would work.

                            More elegant to wire edm or shape the coupling. Sounds like you could sell excess product.
                            The nice thing about the taper lock is that it's reversible. Yes, I could definitely sell splined coupling in this size, but only a few year, I think; my tractor still has the factory paint on the spline.

                            When I needed a a spline coupling for my BX I went to the local dealer and asked for a bent drive shaft and used the coupling end to make my needed drive shaft.
                            They apparently haven't made this stuff in a while, and there are no more replacement parts available. This is a 'vintage' tractor at this point.

                            Have you tried the Orange Tractor Talks forums?
                            Yes, but thanks for the pointer... lots of good reading material there.

                            When I get this loader conversion finished I'll post some pictures; it's back out to the shop and more welding on the subframe today for me.
                            Bart Smaalders
                            http://smaalders.net/barts

                            Comment


                            • #15
                              Barts: Do you happen to have a "gray market" Kubota? If so , many dealers will "dumbass" you and pretend that the parts are not available. Gray market tractors are those Kubota's that were brought in to the states and sold outside the dealer network. They can identify them by the model numbers. Good luck.

                              Sarge

                              Comment

                              Working...
                              X