Gearbox Diagnosis Check (UPDATE Gearbox seal FIXED)

Evening all

Could somebody check my analysis please?

  1. Gearbox oil low relative too level hole
  2. Bevel box oil high - P%**es out :slight_smile:
  3. Some oil in the swing arm gaiter last time I was in there that I though was deliberate to lube the UJ

All adds up to the gearbox outlet shaft oil seal being/getting FUBAR?

If yes how much of a mare is it to do - I can get the bike up to a decent working height and remove the swing arm OK



Hi Tris, analysis sounds about right, with the swinging arm off, the biggest faff is getting the old seal out of the recess, have done it in the past using a pair of cheap small screwdrivers with the ends heated and bent to 90 degrees, the new seal was inserted square with a long series socket though any correct diameter tube will do. Hope this helps. Â Cheers, Gerry. Â

Which model bike is it?

Cheers Gerry
Mike its a 95 Cali (don’t know what happened to my sig? :confused: :confused: )

I’ve not much research yet, but does the nut on the end of the output shaft have to come off?

Yes, the output shaft nut has to come off, this involves tapping flat any raised sections of the soft locking washer. A well cranked ring spanner will fit the nut, or, if using a socket a swift clout on the socket spanner usually works. Watch out for the speedo drive ball which can potentially drop out of the back. A new locking washer is recommended. Nobody ever said it would be simple!


Colinlincs up here did the same job on his Cali last year and “has a tool”

I’m going to talk to him tomorrow and see about borrowing it.

Failing that the workshop people at work are poised to help :smiley: :smiley:

The workshop manual for my bike shows two simple “levers” one for the nut and one to hold the spline when tightening/loosening the output shaft.
It also states a torque of 115-130 lb ft but the text says “tighten firmly”

I’ve been puzzling how set this torque without getting a torque wrench on the thing using those sort of tools.

Then :bulb: :bulb: !!

The manual for the EV (the year after mine) also shows the simple levers in the tool section BUT in the pictures a different tool with torque wrench driving the spline can be seen

I still need to see what Colin made, but all I need is a 27mm (IIRC) ring spanner or whatever fits the nut plus a 10 spline coupler with a 1/2" drive socket welded on the end - simples :stuck_out_tongue: :stuck_out_tongue: :

Anyone got an old spline coupler or a busted UJ they don’t need??

If you have the s/arm off why not use your UJ plus a bar or even the drive shaft to do the job, good idea to check the UJ and associated bits from time to time. Â Cheers, Gerry.

I’ve got these home made tools - The top 2 - that I have used on various Tonti 5 speed boxes over the years. There’s half a splined coupler welded to a spanner and a ring spanner ground down to fit inside the end of the gearbox. PM me if you want to borrow them. I’ve never torqued the nut. Just got it as tight as I could manage.

Cheers John

I’ve got a couple of days off next week and plan to “GO IN” on Thursday. If I can’t do it how Gerry suggests I’ll give you a shout

Hope it all goes smoothly. It’s not such a terrible job. It’s getting to the thing that takes the time.

Well - I started at 0830 and had could see the offender by 1000.

Then remember that I had to drain the GB oil but having the bike up on a centre lift jack I couldn’t get the colostomy bag outta the way. 1100 finished wiping the oil up that had spread itself randomly about the bike, jack and floor. :laughing:

Found that the seal on my bike comes out with the tight nut in place (good call Colinlincs) I used a standard seal hook with the handle chopped of by about 6".
Made an installer from a Austin Montego front wheel inner bearing race and a bit of pipe welded together and knocked the replacement in PDQ.

All back together by the end of the day.

Thanks for the advise and offers of tools chaps :smiley: :smiley: :smiley: