[thelastbaron]

It's possible to use a bearing puller on the output shaft bearing, but what about the input shaft ?



last time around I put the bearings in the freezer overnight and then hammered them in square using a large socket and rubber mallet and a lot of foul language.



Thing is, that was before I'd started to build the engine up from scratch, this time, I'll be wanting to do it with just the gearbox out, without removing the crank etc.



is liquid nitrogen the answer ? or take it to a machine shop to get them to press the bearings in ?



any tips most appreciated

 

[Shep]

The problem I can see here is not getting the gearbox out,which can be done with the engine in situ,but getting it back in.How will you know or manage to get the selector end of the gearbox is correctly aligned/fitted in the rear of the engine.The rollers have to be exact into/under the selector arm.I would not trust it.



I personally would not try to change the gearbox bearings without having the engine out and the rear case off as well of course as the front because of the above.



What makes you think the bearings need replacing?



I have re-built many of these engines from basket case parts and not yet had to replace a gearbox bearing as even the worst engine I had the bearings were usable.Same goes for the Main bearing shells.These rarely seem to wear unlike big-end shells.

 

[thelastbaron]

Thanks for your reply Shep, no I'm not even going to attempt it in-situ... that would be 'orrible.



I'm just hoping for a quick in-out job in one day, as I have all the spare parts from 2 other engines and swapping a gearbox out doesn't take too long.



some of my bearings were a little sticky, definitely had a bit of friction and at speed I think would be a risk with the heat generated.



other concern is the gaskets, I gave them a good thick coating of LM grease on each side, so hopefully they will be re-usable, if not I'll need to source some one of those rolls you recommend.

 

[LRCXed]

Since you are going to have the eng. out and the covers off, use a heat gun or a propane torch to heat up the aluminum around the bearing. It will expand the case and let loose of the bearing much better than putting the bearing in the freezer.

 

[Shep]

Thanks for your reply Shep, no I'm not even going to attempt it in-situ... that would be 'orrible.



I'm just hoping for a quick in-out job in one day, as I have all the spare parts from 2 other engines and swapping a gearbox out doesn't take too long.



some of my bearings were a little sticky, definitely had a bit of friction and at speed I think would be a risk with the heat generated.



other concern is the gaskets, I gave them a good thick coating of LM grease on each side, so hopefully they will be re-usable, if not I'll need to source some one of those rolls you recommend.

Did you get my PM?