jumping out of FOURTH gear

Post by **moggymadmckenzie** » Mon Jun 23, 2008 8:12 pm

hi all - first post in a while so hello to all and i hope you are all well.

ive had the first hicup in a while with my moggy today - its jumping out of fourth gear on acceleration.

it happens when im going from 3rd to 4th and accelerating. generally jumps out at 37mph but if fine when i put it back in.

also happens if i hit a bump.

any thoughts?

new gearbox time? or just worn parts.

cheers

Post by **moggymadmckenzie** » Wed Jun 25, 2008 10:10 am

anyone??

Post by **Rob_Jennings** » Wed Jun 25, 2008 11:29 am

possibly worn/bent selector fork might be repairable otherwise its a new box.

don't be tempted to hold it in gear as you will just do more damage, jsut re select until you can get the unit repaired/replaced

Post by **MoggyTech** » Wed Jun 25, 2008 2:15 pm

If your lucky it might just even be a weak detent plunger spring, or worn plunger. Fault condition would tend to suggest the selector fork isn't pulling the 3rd/4th syncro hub far enough back to lock to fourth gear. Jumping out of fourth is unusual, so gut feeling is the box is OK, but needs new selector fork (or tightened at least), or new detent spring and plunger. The spring and plunger can be done with the box in situ, so try that first. You can also inspect the selector fork, by draining the oil, and removing the clutch relay shaft, and then the gearbox side plate (watch out for two springs as you remove the cover). It might even be possible to tighten the 3rd/4th selector fork bolt through the side cover hole, but it's been ages since I stripped a box down, and can't remember which fork can be tightened it situ.

Also don't rule out something wrong within the remote housing extension. That can be replaced/serviced with the box still in the car. You need to remove the gearbox crossmember and gearbox cover from inside the car, but it is possible.

Post by **bmcecosse** » Tue Jul 01, 2008 9:54 pm

Maybe just worn mountings or gearshift lever loose - since it can happen on a bump ? Otherwise - as MT describes well worth a look inside - all the selectors can be tightened from the side.
However - I would start looking now for a good replacement box to have in reserve - it is likely to only get worse.