Noisy gearbox

[dogsbody47uk]

I have a 1500 Spit gearbox and overdrive in my 13/60. The box is noisy in 1st, 2nd, and 3rd but is (relatively) quiet in top gear. I suspected that worn layshaft bearings were to blame, so I've pulled the gearbox out. I have removed the bellhousing and find that the 3 springs retained by the bellhousing to apply pressure to something? in the gearbox , are missing. What are these springs for, and could they be the reason the box is noisy, . All suggestions gratefully received. Cheers, Dave.

[Nick Jones]

Not sure that all boxes had those three springs (has been debated before on here).  Purpose is to apply some load to the front laygear cluster thrust washer and some say cause it to wear prematurely.

The lack of these springs is unlikely to be the source of your problem.  Noisy in indirect gears will be either

Wear in laygear cluster roller bearings/shaft/internal case hardening

Mainshaft tip bearing problems (less likely in single rail boxes with their bigger tip but still possible)

Input shaft ball race very worn.

Nick

[Pete Lewis]

The springs were an anti backlash rattle idea to quieten gear noise at idle  just preloads the cluster  , believe it was soon deleted 

I would agree its mainshaft spigot layshaft spindle or input bearing is causing the noise 

Sorry the idea of 3 cheap springs wont solve your noise    

 you can add them on a rebuild   

[dogsbody47uk]

Thanks for the information Nick and Pete. I shall carry on stripping the box down to see what's worn out. Cheers, Dave.