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Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 9:04 am
by gs.davies
What's the best and least destructive way of removing the first motion and double roller bearing?

I'd like to attempt transplanting a gearset from an 22G1832 into a 22G846 box, and if they're serviceable for now, the bearings too. I suspect the 1832 gearset is in good condition.

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 10:04 am
by Richspec
check out classic mini diy on youtube, rod change gearbox parts 1-3.

part 1 covers dismantling, theres a special tool from guessworks that helps drive out the double roller.

https://youtu.be/KEcx0y7vuGg

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 10:26 am
by Fanfaniracing
There is a Special Tool for this. I don't remember the Churchill number.

It's looking like a C.

May i can take a Picture for you tomorrow

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 1:42 pm
by iain1967s
I used a sharkbite 3/4” plumbing clip release tool

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 3:33 pm
by Richspec
Brew time so had a look for said tool :D

http://www.guess-works.com/Shop/Parts/d ... htm?id=491

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 3:36 pm
by gs.davies
Good stuff. So that'd be the third motion shaft out, what about the first motion shaft? Think that has to come out first and the Haynes manual talks about using a brass drift. Is there a 'safer' way to pull it than that?

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 3:49 pm
by GraemeC
The C shaped tool can be made from a stack of big washers with a slot cut out - sometimes this can be easier as you can build up the stack gradually as the bearing starts to move.

The nice way to remove the first motion is to make a slide hammer attachment that screws onto the 1st motion shaft nose in place of the input gear nut.
The other way is to use use the mainshaft to drift it out. This also then opens up the gap for the tool of choice for the 3rd motion bearing.
However, cover the shafts with a rag as the synchro balls will make a bid for freedom.

Interestingly, Guessworks advises drifting the 3rd motion bearing out by its centre, not by its outer race. Apparently it does less damage to the bearing and if it does fall apart, then it was buggered anyway.

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 3:59 pm
by gs.davies
GraemeC wrote: Fri Mar 05, 2021 3:49 pm The C shaped tool can be made from a stack of big washers with a slot cut out - sometimes this can be easier as you can build up the stack gradually as the bearing starts to move.
Neat idea!
GraemeC wrote: Fri Mar 05, 2021 3:49 pm
However, cover the shafts with a rag as the synchro balls will make a bid for freedom. I REALLY don't fancy trying to reassemble a syncro hub.. I'm capable of colourful language but I'm not sure I actually have the stamina for swearing that looks like it requires..
I presume this is because the syncro hubs get pushed past the limits of travel of the selector forks? I REALLY don't fancy trying to reassemble a syncro hub.. I'm capable of colourful language but I'm not sure I actually have the stamina for swearing that looks like it requires..

GraemeC wrote: Fri Mar 05, 2021 3:49 pm
Interestingly, Guessworks advises drifting the 3rd motion bearing out by its centre, not by its outer race. Apparently it does less damage to the bearing and if it does fall apart, then it was buggered anyway.
How would that be acheived? Presume the mainshaft still gets nudged towards the flywheel side to open up a gap to get to the bearing and then go at it with a drift I suppose..

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 4:05 pm
by GraemeC
gs.davies wrote: Fri Mar 05, 2021 3:59 pm
GraemeC wrote: Fri Mar 05, 2021 3:49 pm The C shaped tool can be made from a stack of big washers with a slot cut out - sometimes this can be easier as you can build up the stack gradually as the bearing starts to move.
Neat idea!
GraemeC wrote: Fri Mar 05, 2021 3:49 pm
However, cover the shafts with a rag as the synchro balls will make a bid for freedom. I REALLY don't fancy trying to reassemble a syncro hub.. I'm capable of colourful language but I'm not sure I actually have the stamina for swearing that looks like it requires..
I presume this is because the syncro hubs get pushed past the limits of travel of the selector forks? I REALLY don't fancy trying to reassemble a syncro hub.. I'm capable of colourful language but I'm not sure I actually have the stamina for swearing that looks like it requires..

GraemeC wrote: Fri Mar 05, 2021 3:49 pm
Interestingly, Guessworks advises drifting the 3rd motion bearing out by its centre, not by its outer race. Apparently it does less damage to the bearing and if it does fall apart, then it was buggered anyway.
How would that be acheived? Presume the mainshaft still gets nudged towards the flywheel side to open up a gap to get to the bearing and then go at it with a drift I suppose..
The synchro outer is held by the selector forks, however the inner moves with the mainshaft - eventually it moves far enough that the balls become exposed and the springs launch them out. You'll be lucky to avoid it to be honest but rebuilding the synchros isn't difficult, just a bit fiddly.

I think the Guessworks tool will naturally push on the inner race of the 3rd motion as that race is slightly prouder if I remember rightly.
Some of the original factory tools were relieved in the middle so their outer edge would push on the outer race of the bearing.

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 4:19 pm
by gs.davies
I'll just have to have a go at it. Fingers crossed the bearings don't collapse (or is more likely, I destroy them getting them out)

Mind you, given that the selector mechanism is jammed on this box (somehow the selector crank has ended up with its lever facing the flywheel side.. :roll:

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 4:51 pm
by Herbert
WHere abouts are you ? Ive got all the Churchill tools needed. I wont lend them out....R

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 5:21 pm
by Spider
There's some good and clever suggestions for the Mainshaft Bearing Removal Tool.

This is the one I made some 40 years ago, from another bearing;-

Image

I did make a tool similar to the factory one a few years back, but I still prefer this one.

Oh, if if following some of those video guides, some talk about heating casings to remove some of the bearings. This is the factory's advice regarding that practice;-

Image

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 6:22 pm
by gs.davies
Rolandino wrote: Fri Mar 05, 2021 4:51 pm WHere abouts are you ? Ive got all the Churchill tools needed. I wont lend them out....R
I’m in Maldon. essex.

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 6:38 pm
by swifty
Before I bought the guessworks tool I used three primary gear " C" rings taped together .... ken

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 8:32 pm
by InnoCooperExport
I used a brass drift and tapped it round, but maybe not the best way to do it for reusing the bearing.

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 8:48 pm
by Fanfaniracing
Assembling a Synchro Hub is one of the easier tasks on rebuilding a gearbox.

With the right Tools of corse...

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 9:16 pm
by JohnA
Why do these people make such videos when they have little knowledge or experience ?
Are they on some sort of ego trip ?

Re: Removal of Gearbox bearings

Posted: Fri Mar 05, 2021 9:27 pm
by gs.davies
JohnA wrote: Fri Mar 05, 2021 9:16 pm Why do these people make such videos when they have little knowledge or experience ?
Are they on some sort of ego trip ?
I know. So much confusing info for people out there.

Re: Removal of Gearbox bearings

Posted: Sat Mar 06, 2021 12:33 am
by Richspec
JohnA wrote: Fri Mar 05, 2021 9:16 pm Why do these people make such videos when they have little knowledge or experience ?
Are they on some sort of ego trip ?
on about Coles vids John?
He does stress he's an amateur and welcome to comments and corrections.!

Its called sharing the knowledge, if you think he doesn't know much then you'd be shocked how little newer younger owners know :shock:
Its err illuminating at times!!