One minute it was OK, the next a great puddle of oil.
Traced it to the kick start shaft, ordered up 2 new rubber seals (spare just in case) and gear box gasket.
I remember looking at that oil seal when I checked over the gearbox and thinking hmmm that looks a difficult one I'll chance it.
So any tips on changing the seal, as I remember there was a bush behind it hence my reluctance to replace it. Does the bush need to come out and if so should it be replaced.
Thanks in advance.
HI John If it is not a MK 3 just hook the old seal out with a small screw driver and replace it with a ( x ring seal No 0.40006 from Andover Norton
It's worth checking if kick-start shaft Bush is oval, and needs replacing, while you have it in bits.
Happened to me, suddenly started leaking cold
Its nothing to be worried about. If the shaft is a sloppy fit in the bush, warm up the casing and press or tap out the bush with a suitable size socket turned upside down.
Stick the new one in the freezer for an hour then drop it in whilst the casing is still warm. Simples...
Get a double lip oil seal if possible.
The aperture in my alloy gearbox end cover has too large a diameter to take the standard seal. So I have to fill the bottom of the groove with silicone before inserting the seal. This works fine - but is it original? Might it be because the previous owner (who I know was a good machinist) bored it out oversize to replace the steel bush? I did consider buying and fitting a lip seal in the groove behind the bush, but I could not get the bush out (even when heated). Also I can't remember but I think the groove is too narrow for a lip seal. I do know that some Norton dealers (e.g. Russell Motors) used to have a milling machine set up to recess the alloy to allow a lip seal to be pressed in.
My x-ring has worked well enough for some thousands of miles, and obviously they are much easier to fit (and replace).
Many thanks for all the tips, I will pay more attention to the bush and seal when I take it to bits, I assume the bush is original as the bike was pretty much standard. I did replace the kick start shaft and not the seal so was asking for trouble really.