Power Major Gearbox Top Shaft Thread

[oldblue]

Hi All, does anyone know what thread type is on the top shaft of the gear cluster on a power major?
My dads one has a captive nut on that fell out when we pulled the gear cluster out of the box. It maches upto the hoffman type bearinng on the top shaft. We found the nut but it has been floting around for a while and stripped the thread and we can't match the nut up.
Looks like a very fine thread on the shaft.
Any ideas anyone?

[henk]

All threaths are UN. So the normal type is UNC and the fine one will be UNF.

[Timeee]

Sadly, the parts list does not list it as a "standard part", where they normally give the specification of the thread and nut size. If what you describe is what I think it is, it is a special locknut, round, with 4(?) grooves down the sides to take a special tool needed to tighten/undo it, Part No E85-GA-9. There is also a locknut retainer fitted before the locknut, (Part No E95-GA-9) which would appear to have gone missing somewhere in your gearbox as well. I suppose one has to ask the question why did Fordson fit a special locknut and retainer, rather than a plain, old, simple hexagonal nut with lock tab, or split pin? Sorry, I probably haven't helped at all. Tim

[BearCreek Majors]

Hi Old Blue, search one of my old posts, Super Major live trany, and let me know if this is the same nut. its just a standard fine thread spanner nut, I'll look through my file for that tractor to see if I have the info on it.

Pat

[oldblue]

Thanks Both, and yes it does have 4 slots in the locking washer is still attached to the nut and the keyway in the shaft has failed causing the nut to undo. We were thinking of putting a castle head nut on and drilling the shaft to take a split pin?
Thanks
Shane

[BearCreek Majors]

Hi Shane, I couldn’t find an invoice for a spanner nut and the more that I think about it, I may have used a lugnut from a 1ton Ford truck and Loctite to hold it. Be sure to check the half moon key to make sure it hasn’t been sheared, if I remember correctly when the nut comes loose it forces the two shafts together and as they are not rotating at the same speed they tend to want to friction welded the ends together.

Pat