HAVE I DONE SOMETHING STUPID?

[Jeremy R65]

Dear all

I replaced the gearbox neutral switch over the winter and, to do so, had to remove the gearbox top bolt spacer that gets in the way.  It was a bugger to get out.  Anyway, switch replaced I tried to put the spacer back..... It was not even close to an interference fit.  It seemed that the gearbox casting had dumped some locked in stresses and the spacer was now about 0.5mm too long at least. Try as I might I could not get the bugger back, so I stuck it in the lathe and turned a bit off to get a decent interference fit and thought no more of it.  I mentioned this recently to a friend who has had airheads for years, who said YOU CAN'T DO THAT!  Questions - can I?  If not, what should I have done? If not, how do I put it right?  If I need a new spacer what is the correct length so I can turn up a new one? Do I win twat of the month?.  All comments gratefully received..........

[Barry]

Those spacers are always a bear to install but perhaps not as tight as yours was.  Freezing usually helps but that wouldn't have made a difference of anywhere near 0.5 mm.  If it's still an interference fit I wouldn't worry as the object of the thing is not to stress the engine casing and being 0.5 mm too long would stress the casing just as much as being too short.

As to the length I noticed on the parts fiche that they come in two sizes 108 mm and 110 mm.  Anyone know the reason for that ?


Edit

I just calculated that the very most you could expect to achieve by freezing is to shorten the tube by 0.1 mm or 0.004"  So it was never going to go back in at 0.5 mm too long.  In the ideal world you would have turned  0.4 mm of the length.

[Jeremy R65]

Thanks Barry.  My notes tell me I turned off 0.5mm and it was still a "hammer fit" so I was happy with it at the time - but I was starting to imagine what horrible things could be going on inside my distorted gearbox!

[wilcom]

I did the same thing when I installed my switch. I "shined" the ends with a grinder until I was able to get it back in. It was still a "OMG it's tight" fit.

You always think, " If it came outta there it's gotta go back in, Right"

{{{{WRONG}}}}}

[Bob_Roller]

I have dry ice available at two grocery stores , dry ice works great in this application .

[Barry]

Dry ice at - 109 F would be a big improvement on a normal freezer and might shrink the spacer by as much 0.3mm or perhaps even 0.4mm in Bob's neck of the woods when it's 120F outside.

[Tony Smith]

I am feeling a little lost here, can someone please post a photo of the location of these spacers, and, if possible, a spacer please?

[mrclubike]

  but I was starting to imagine what horrible things could be going on inside my distorted gearbox!

The spacer is in the engine not the "gear box"

Sounds like it is a better option to just remove the gear box and do a spline lube
You may be doing it again soon because the switches are prone to leaking
When i installed  a new one (for the second time) I went ahead and covered it in epoxy before it started leaking 

I assure you  I am never going to remove my spacer    

[georgesgiralt]

Hello !
A long time ago I had to put this spacer back in place and could not achieve it lying on the floor with the hammer too close to my head to be of much use.
So I grinded a bit the spacer but not for the whole surface, only about 1/3 to 1/2 of the section.
This way I was able to position it in the correct place and hammer it back in place .... Just my 2 cents ...

[peteremc]

I am feeling a little lost here, can someone please post a photo of the location of these spacers, and, if possible, a spacer please?

Yes, what Tony said. I also have no idea what part is being discussed.  Thanks

[Jeremy R65]

Sorry guys, I did not mean to confuse.  The switch is in the bottom of the gearbox, the spacer that has to be removed is on the top of the engine sump. The long stud that holds it all together also carries the exhaust down pipe brackets both sides. See picture.

[Barry]

I don't know why you guys are confused as there is only one spacer that needs moving to get at the neutral switch.  I know the op did say "gearbox casting" but I didn't like to correct him even though I still referred to it as stressing the "engine casing"  in post #2.

[Tony Smith]

I don't know why you guys are confused as there is only one spacer that needs moving to get at the neutral switch.  I know the op did say "gearbox casting" but I didn't like to correct him even though I still referred to it as stressing the "engine casing"  in post #2.

My problem was that I could not envisage that particular spacer because you shouldn't mess with it and you can change the neutral switch without touching it.


Now please don't ask me for a "blow by blow" but I have changed a number of them over the years and have *never* touched the engine mounting bolts too do so.

I was about to say that all the ones I've changed were pre-81 and perhaps there is a difference, but then I remembered the last one I changed - near 20 years ago, was a 80's era G/S and I definitely did not remove anything other than the engine and gearbox oil (service being done anyway) and  fuel tank an so that we could lay it on its side for easier access.

[Bob_Roller]

Tony, what is your technique for replacing the switch any specialty or custom made tools ?

 I've got a replacement coming up when it cools down here in November .

I just found out, that I now have access to liquid nitrogen at work, that should shrink that spacer if I ever need to remove it !!!

[Tony Smith]

Tony, what is your technique for replacing the switch any specialty or custom made tools ?

Bob, No special tools, although I do have flat ring spanners, low profile ring spanners, curved "obstruction" ring spanners and ratchet ring spanners, so I may well have used one or more of those.

As I said, I do not recall specifics, but I do recall a lot of swearing and some degree of frustration, particularly in putting the new one in, I seem to recall "balancing" the new switch on my index finger and applying an upwards pressure whilst turning the body of the switch to get it started on the threads.