BSA Gearbox rebuild Plunger M Model - STD gearbox

[Barrieh]

Gents,

I need some assistance. Gearbox BSA M33 1955 plunger -

1. Oil Seal - Sprocket side - Do I press the oil seal in from the outside and into the case - seems easy to do, or is it a nightmare fat hands pressing in from the inside out?

2. Replacing the main bearings - How on earth do I get them back in, any hints or tips

Hamish

[Pete C]

Not sure about the oil seal but I should think it is pressed in from the outside, just make sure it goes in square. My gearboxes are the earlier type - no il seal.

The bearings in the cases (inner cover bearing and the one the pinion sleeve rides in) I always do by heating the cases to around 100°C and putting the bearings in the freezer for a few hours, they should then drop into place. It's all fairly easy if you have the gearbox apart and out of the bike. You need to be quick with the chilled bearing in the main case and have a mandrel or similar  handy to tap it into place.

good luck
cheers
Pete

[Barrieh]

Thanks Pete,

I will have to wait until my wife goes out before commandeering the oven I can see her face now... What the ---- do think your doing!

I will give that a go tomorrow.

Hamish

[morven21]

Instead of oven, could use old saucepan full of boiling water.  You do need OLD pan, tho, or risk being shot on the spot, same as with oven!

[Pete C]

If you run the cases through the dishwasher first, there is very little smoke and smell when you put them in the oven 

[morven21]

Ah, Pete?!

[Barrieh]

Hi Guys,

So I cleaned it up first with a good scrub in the kitchen sink and popped it into the oven, 100c, for 10 minutes.... popped it out and the bearings just fall in... easy peezy

No problem at all.

Thanks
Hamish