Kubota B2100 Mid Mount PTO Leak

repair

Mid mount PTO leak

My B2100 has a mid-mount mower deck and there’s a leak. I know the PTO shaft seal is fairly new, so I didn’t think the leak was there.

leak

I took off the mower deck, cleaned the hydraulic fluid off of the components and determined that the leak is coming from where the housing meets the tractor body, rather than the PTO shaft.

Here it is all cleaned up:

pto

In the diagram from Kubota, the leak was between part 010 and the large housing above it.

diagram

While I had it apart, I replaced the o-ring (part 120 on the diagram). I ordered a new seal for the PTO shaft (part 050) but the existing one was brand-new-looking so I opted to not replace it.

This is a fairly easy job, all things considered.

  1. Drain the hydraulic fluid (there are 4 different places you have to remove bolts from to do this)

  2. Unhook the shift-lever (the thing that connects to part 100 in the diagram)

  3. Drop the assembly down after removing 4 bolts

    NOTE:

    Part numbers 180 and 170 are the spring and bearing that “lock” the lever in place at the top and bottom of its range (there’s an indentation in part 100 that the bearing fits into to make the lever stick at each end of its travel)

    When I took the thing apart, the bearing fell down into the gear and was not visible underneath part 070 - if I hadn’t carefully looked at the parts diagram I would not have noticed that bearing was loose in there and would have torn the mid-pto all to hell when I engaged it.

  4. Replace the o-ring (120) for the shifter (you have to pull out 130 to remove the shifter (100))

  5. Clean the mating surfaces (I scraped with plastic and used acetone to clean it up)

  6. Apply gasket compound to the clean mating surface

  7. Re-assemble, making sure you have all the small parts (e.g. the bearing) in the correct places.

  8. Refill with hydraulic fluid after the gasket sets

  9. Crank it up and test it

Note that my PTO shaft seal was good, so I opted not to replace it. Probably best to do what I did and order one to have in case you need it, because you have to drain the whole thing to replace it and if you think it might be bad just go ahead and replace it.