transmission modifications

[otis71]

Needing a new transmission case to get the 26 JD up and going I have looked in a lot of places. I found one today at the Chesapeake chapter meet. On a lot of cases I have noticed the shoulder on the sprocket side has been machined and in some cases crudely cut off. What purpose does this shoulder do and why are so many cut off? Thanks.

[MMasa]

Not sure what you are talking about. Pictures? Do you mean a VL case that has the inner primary mount cut off?
Mark

[Steve Slocombe]

Dear Otis, if you've bought a VL case with the ear cut off, it won't fit your JD because the adjuster bolt won't line up with the frame. The 1926-29 JD box must be more common, as I come across them fitted to some VLs and giving a similar adjuster bolt problem. JD gearbox cases from around 1925-28 are stamped on the side with a date code such as 26-1234, so should be reasonably easy to identify.

[otis71]

Shoulder

Not sure what you are talking about. Pictures? Do you mean a VL case that has the inner primary mount cut off?
Mark

Here is a picture of one cut and one not. I have seen it on several JD cases. I am aware of the VL modifications made in case of a thrown chain but this is different.

[MMasa]

I think I see what you mean now. The area of the case where the main drive gear comes our is a different length. That isn't cut off, there are just two different lengths depending on the year. The main drive gear and bearing got longer in 1925. I think that you may just be looking at different year cases. How are they stamped on the back?
Mark

[otis71]

Here is one I encountered that was crudely cut. They both were modified JD.

[otis71]

Late model JD stamped with 26 in the casting number.

[Robert Luland]

These trannys where used for everything you can imagine. From farm machinery to manufacturing. The thing is no matter what your mating them up to. It can't be used the way it is. You need a flat surface. So you hack off what you don't need. And mate it to what you need. Rather simple when you think about it. Just because some entrepreneur has it at a swap meet or on fleese-bay doesn't me it came off a motorcycle. Bob L

[MMasa]

I've never seen one cut like that and I must have 50 cases. Bob is probably right that it was modified to use in some other application.
Mark

[otis71]

What purpose does that shoulder serve, to keep dirt out of the bearing? Do you think it will effect it for use?

[Robert Luland]

Yes and no. If I remember right there is a slinger washer that goes in there. Basically, any oil leaving gets thrown back into the lip to the drain hole at the bottom. Would it make that big of a deal? I don't think so. Mark would no better. Bob L

[Jerry Wieland]

What purpose does that shoulder serve, to keep dirt out of the bearing? Do you think it will effect it for use?

I have fixed 2 similarly modified cases although yours appear to have been done on purpose. Mine both looked to have been worn away. I just machined a piece that replicated the piece and welded it on there. I suspect it was meant to divert leaking oil away from the clutch.

Jerry

[MMasa]

Bob and Jerry are correct. The missing portion acts as an oil catch. Will it work like that? Yes, but it could get messy.
Mark

[Peter Cooke]

Wouldn't using a sealed bearing on the main drive gear eliminate the need for the 'oil catch'?

[MMasa]

No. It will still seep out between the mainshaft and the main drive gear.
Mark