I use SKF bearings from: http://simplybearings.co.uk/shop/index.php and usually replace the roller bearing on the input shaft - though occasionally I'll just replace the inner sleeve, which is available from Matt Beekers at: http://bmwboxersupplies.com/.
I'll cut a circlip groove in the output shaft if the box doesn't have one - it costs me nothing to do and the circlip is a couple of pence. It could extend the life of the box though.
I take about eight depth readings for each bearing housing in the rear cover and then shim to the tightest with a clearance of 0.05mm. The box is usually running free when warm, but can be tight when cold. I then make a decision - is it too tight ??
If I think it is I'll start again and drop the shimming by a couple of thou'. The aim being to have it turnable by hand when cold but free when warm. The difference in shimming between tight and free is minuscule.
Nowadays I'll put oil in the box and run it in my lathe for a while - making sure that it goes up and down the gears properly. The oil is drained (and checked) before the box is posted back.
Right now I'm rebuilding a Transfer Box from a Toyota Land Cruiser 'Colorado' for a guy in the Isle of Man (he could be a useful contact). It is full of rust and is taking me an inordinate amount of time to sort out. These jobs are fine as long as no-one is in a hurry as I have plenty of my own work to do
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Bob.
Do you do 1150 Oilhead gearboxes too?
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). So I have some experience of them. I keep thinking that I should rebuild the box from my 1150 GSA as its had a bit of a hard time in some very hot countries, but its not been a priority.
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