Help!!! 3rd and 4th gear not selecting

[Jabbawocky]

Hi

The only difference between the 6 pot and 4 pot gearbox of a particular type are the bellhousings. With Series 3 gearboxes do not mix the internals from A, B, C, type gearboxes with D type gearboxes.

Mick

[DrivingDutchman]

Found what is the problem with the orininal box of Dora. The main shaft has snapped in 2 just behind the synchro mesh...

That's going to be a complete rebuild I guess.

Michiel

[RMS]

Oh dear - lucky you managed to get it to Billing and back like that!

I think it's not an uncommon problem - I know there has been talk of it being a weak point, something to do with the manufacturing process not leaving a radius where it's been machined

If you're just after a quick fix you might look to buy a second hand gearbox, 2 or 3, and swap your bellhousing.
Of course, you might be lucky and buy a good box, or you might get one that jumps out of gear etc. but at least you'd be back on the road - Luck of the draw

Cheers,
Robin.