Just finished the mainshaft nut fix and a clutch change on my F78, silly me forgot to check the gearbox before putting the engine back. now the stick is stuck in neutral and can't be moved anywhere except between the neutral positions of 1-2 and 3-4 (i.e. not to the far right). have tried turning over the engine and also pushing the vehicle with/without clutch engaged. the engine does get turned so the box is working, it's just that the stick is totally jammed!

could this be caused by doing the mainshaft nut too tight? i didn't have a meaty enough torque wrench so just used an extension bar, however if anything i'm pretty sure i tightened it to under the 200ft/lbs.

anyone have any brilliant ideas before i take the engine out again?



Check you have not damaged anything externally first, then remove the gearstick from inside the vehicle by removing the centre console, the rubber gaitor, and the circlip which holds the gearstick in.
Try the gearstick with the circlip removed, if it works you have strained something, if not insert a screwdriver and try to operate the various selectors. It is doubtful thet you have overtightened the nut as i torque these up to more than twice your setting with no problems.

The only problems i have ever had is the selector rails roll pins coming out, these prevent the selector rails from spinning into position for the 1/2 - 3/4 gear planes.

many thanks. took the engine

many thanks. took the engine back out, took off the top of the box with the selector etc, was fairly dirty so thoroughly de-gunked the selector mechanism and greased with moly, seems to be working now at least on the bench. will re-fit to the box tomorrow and let you know what happens. the cleaning and moly grease has seemed to make it a lot smoother and easier to move.

problem solved. it appears

problem solved. it appears it was a combination of the selector mechanism being full of crud and one of the seolector arms in the gearbox itslef that was slightly jammed. slapped on loads of moly grease and put it back on the box and it seems to be fine now. thanks assassin for your help. cheers.