Author Topic: Gearbox oil leak  (Read 639 times)

Offline Slash

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Gearbox oil leak
« on: 27.08. 2022 16:26 »
There is a leak from the gearbox makeshift area, the oil level.in the box has dropped and there Is a horrible mess on the garage floor
Is this likely to be the main hearing seal or around the shafts? I see srm make a seal in the sprocket nut, so I guess it's a known problem.
1961 Tribsa

Offline RDfella

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Re: Gearbox oil leak
« Reply #1 on: 27.08. 2022 17:48 »
Quote
There is a leak from the gearbox makeshift area, the oil level.in the box has dropped and there Is a horrible mess on the garage floor

"They all do that, Sir"  Including mine. I find leaks are a lot less when the bikes are on the centre stand as opposed to side stand.
'49 B31, '49 M21, '53 DOT, '58 Flash, '62 Flash special, '00 Firestorm, Weslake sprint bike.

Online muskrat

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Re: Gearbox oil leak
« Reply #2 on: 27.08. 2022 20:37 »
G'day Slash.
The two places they can leak is the sprocket oil seal or between the main shaft and sleeve gear.
Does it leak when topped up and put on the center stand?
I have one of those "oil seal nuts" on the Cafe (won't fit on the plunger). At least changing the sprocket/sprocket seal/nut is an easy job compared to a plunger!
Cheers
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Offline Slash

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Re: Gearbox oil leak
« Reply #3 on: 28.08. 2022 06:47 »
Hi Muskrat
Yes it does leak when topped up to the level plug while on the centre stand. There is no side stand on the bike, I have been searching for one of those.
 I guess the remedy is to strip the primary side and replace the seal, and use the SRM sprocket nut.
cheers
Slash
1961 Tribsa

Online morris

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Re: Gearbox oil leak
« Reply #4 on: 28.08. 2022 11:05 »
SRM sprocket nut highly recommended
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Offline Slash

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Re: Gearbox oil leak
« Reply #5 on: 28.08. 2022 11:40 »
Thanks, one has been ordered!
1961 Tribsa

Online chaterlea25

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Re: Gearbox oil leak
« Reply #6 on: 28.08. 2022 12:59 »
Hi Slash,
While you are that far into the workings, its worthwhile changing the sprocket oil seal as well
I have seen many of these leaking because the circlip has not been fitted correctly, it can be a PITA to get it solidly into place, check the sprocket for wear where the seal runs or take the opportunity to change it if any wear is found
Clean around the end of the selector shaft and layshaft bush ends and seal with a smear of your favorite goo

John
1961 Super Rocket
1963 RGS (ongoing)

Offline Slash

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Re: Gearbox oil leak
« Reply #7 on: 03.09. 2022 12:47 »
Hi
I've ordered a new gearbox seal and circlip, I'll change it all while I have it apart.

Thanks!
1961 Tribsa