37 4G oil valve and gearbox questions

[markus.nikot]

Hello everyone,
today, I drove Cammy and 4G for the first time in seven months – still a bit cold but a lot of fun!

I'm still breaking in the 37 4G. I've just worked on the pistons for the third time, and they seems to be working, but I have some questions about the gearbox and oil valve.
How do I adjust the oil valve at the bottom of the timing case? Unfortunately, I can't find anything about this in the literature. Does it work the same way as on the early Cammy?
I've already taken the gearbox apart a few times because the gears were jumping out. Third and fourth, regardless of whether under load or not. I just can't find the cause. The dogs are OK, and so is the shift setting, in my opinion. Any ideas?

Markus

[Roger Gwynn]

See page 12 of 1939 owners guide under 'Notes on oil supply'

Gearbox problems are likely to be that the gears are not fully engaging, could be end float on either shaft, worn selector forks, worn selector pins. They do not engage very far so a little wear can cause big problems. Even thicker gaskets are enough to cause problems. The mainshaft should have 1/64" play, i.e. minimal, designed to make sure that the bearings are not put under load. Good luck.

[markus.nikot]

Thanks, I'll check this