Bsa B31 Plunger, Gearbox refurbishment Part 1

B31 Gearbox refurb including new bearings bushes and seals

[@binnawan]

It may have been a good idea to leave one of the seals in the new bearing, on the outside. It would prevent oil even getting to the oil seal. Baz

[@hunterjamison4808]

Thank you so much for going deeper into the old gear box! I’d made a new bush for that area too. We had some aluminum nickel bronze bar ends so that’s what I used. I’m curious why you used stainless instead of bronze🤔. When I installed the new seal it made it turn alot slower. I’’m hoping it wears in eventually. My complete gear assemblys needed some better less-worn gears which I found on ebay. Just hoping that I got the spacers correct in them. It’s great watching you do all these projects!

[@500dbd34]

Hunter, Thanks for your comment, always appreciated. I guess you have noticed that I am not a precision engineer or bearing expert but over the years I have pressed out many steel bushes from gearboxes. I sometimes buy ready-made bearings but there’s no fun in that. Where “spinning” shafts are concerned I would always use Phos_Bronze or iolite type bushes but on kickstart and gear lever shafts which don’t spin I have no problem with stainless as there is less chance of corrosion. I’ve checked the subject on Google and it seems stainless is OK. If any experts out there can advise me further it would be appreciated, sharing knowledge is what KZbin is all about Cheers B

[@davidclapham1066]

Nice work Brian! Do you feel the gearbox bearing will last longer running in oil as opposed to leaving the shielding on and letting it run in it's own grease?

[@500dbd34]

Dave, another good question.The BSA bearings I pressed out were Hoffman un- shielded That’s why I removed the shielding, I guess the White Grease in the bearing will dissolve in the oil in the gearbox over time. I bought a second gearbox for spares and noticed that it was full of White Grease when I took the covers off and I would worry that the grease would not reach all the moving parts in the box. I’ve noticed some guys on the BSA forums do prefer grease but I guess it’s to reduce the chance of oil leaks. Thanks again, great comment. Cheers B

[@tomeli282]

Hello Brian, I have a 1949 BSA A7 plunger with a rumble in 3rd gear, do you happen to take in rebuilds please? Regards Huw (Swansea)

[@500dbd34]

Sorry Hew I’m not able to help you with this, try SRM IN ABERYSTWYTH they may be able to help or Phil Pearson in Gt Yarmouth. Good luck. Cheers Brian