English French German Italian Spanish

Mk3 Neutral switch

Submitted by allan_walker on Tue, 30/08/2016
Forums
Commando

I've owned my Mk3 for a few years, and I'm in the process of putting right what the previous owner did when he 'restored' it.

The neutral light in the console has never worked. The entire wiring loom was a mess anyway, so I have replaced it. I peered under the gearbox looking for the neutral switch, and there isn't one.

Not only that, there is nowhere for it to go (i.e. there is no threaded boss in the gearbox casing near the camplate pivot bolt,) so it seems that my bike has an earlier gearbox shell. Perhaps the original was damaged when the layshaft bearing collapsed....

My question is, would it be feasible to modify the existing shell by welding a threaded boss in the appropriate place to accept the neutral switch? Has anyone any experience of this?

I realise that I'll have to remove and strip the 'box to do this, but such a modification should be a lot cheaper than buying a new Mk3 gearbox shell.

Submitted by martin_freeman on Tue, 30/08/2016

Permalink

Allan,

you may be expecting too much, just had a look at mine and there is no boss, may have been spot faced but hard to see as locknut covers surface, position is low down near camplate plunger, yours may have threaded portion snapped off level with surface. you may well be able to drill/tap case but problem is where to drill and what is thread on switch.

have a look on top of gearbox between engine plates - what is number that should identify if case is Mk111 or not.

regards Martin

Submitted by richard_payne on Tue, 30/08/2016

Permalink

The 'boss' into which the thread for the neutral switch is tapped is actually on the inside. There is only a faced area on the outside as a giveaway.

As Martin says, gearbox number on top lug should tell you if it is a period Mk3 shell (replacements are unstamped). Numbers matched engines so began at 325000.

I wouldn't risk tapping case wall without boss - but watch out as a slight misadjustment of the switch will foul the domed striker on the camplate so the boss will have to be just-so and on the correct radius from the plate axis.

In my experience, these switches are temperamental things at the best of times. Not helped by the fact that the only way to set them in-situ involves the wires twisting and catching on the crossover shaft as you turn the body.

Submitted by allan_walker on Wed, 31/08/2016

Permalink

Thanks Martin and Richard.

Taking your comments on board, and after studying the picture of the Mk3 gearbox shell on the Andover Norton site, it seems that converting the existing shell to accept the neutral switch falls into the too-difficult-to-do category.

I need to replace the layshaft bearing anyway, so whilst I'm in there I'll see if there's any damage to the shell (like a crack between the two bearings.) If there is, I'll definitely buy a new shell. Otherwise, I'll make-do without the neutral light.

 


Norton Owners Club Website by 2Toucans