Serious gearbox oil leak

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Ragtop733
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Serious gearbox oil leak

Post by Ragtop733 »

I have a serious oil leak on the gearbox of my 1960 948cc minor. I have replaced the output shaft seal but the oil runs out at the flange to the propshaft. Otherwise the gearbox runs well, no noises or gear issues. The oil leak is consistent and leaves a large pool of oil every time I park up, any ideas or advice would be appreciated
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svenedin
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Re: Serious gearbox oil leak

Post by svenedin »

Presumably it's the rear oil seal part 10G199. I'd have to look up in the workshop manual how this is replaced.

See the ESM catalogue: https://www.morrisminorspares.com/catalogue-i30

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
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geoberni
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Re: Serious gearbox oil leak

Post by geoberni »

I don't know why ESM use 10G199; the original parts list number was 2A 3061, which is widely used by other sellers for various makes/models, including Midget I, Midget II, Minor 1000, Sprite I, Sprite II, & Sprite III.
So there's plenty of sellers out there to find the best price.

I didn't notice the guy remove the old housing/seal on his video, but see here for hammering the seal on....https://youtu.be/2gFDfmidbPQ?t=903
Basil the 1955 series II

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BILLYWIZ
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Re: Serious gearbox oil leak

Post by BILLYWIZ »

I had an oil leak with the rear oil seal on the gearbox of my car and decided to replace it 'in situ' lying on my back with the car up on axle stands.
Getting the old seal and housing off was interesting, although it is just a push fit onto the gearbox housing it was very tight, it took quite an effort and patience tapping it off especially in very little space to wield a hammer! Fitting the new seal was straight forward gently tapping it on with a block of wood to prevent damaging the seal also making sure the seal was centred on the housing and well lubricated. Oh for a four poster lift, no such luxury!
Bill.
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svenedin
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Re: Serious gearbox oil leak

Post by svenedin »

BILLYWIZ wrote: Mon Apr 14, 2025 7:29 pm I had an oil leak with the rear oil seal on the gearbox of my car and decided to replace it 'in situ' lying on my back with the car up on axle stands.
Getting the old seal and housing off was interesting, although it is just a push fit onto the gearbox housing it was very tight, it took quite an effort and patience tapping it off especially in very little space to wield a hammer! Fitting the new seal was straight forward gently tapping it on with a block of wood to prevent damaging the seal also making sure the seal was centred on the housing and well lubricated. Oh for a four poster lift, no such luxury!
Bill.
If I ever win the lottery I want a 4 post lift! Imagine being able to do jobs sitting on a stool comfortably.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
les
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Re: Serious gearbox oil leak

Post by les »

Incidentally regarding the rear seal, yes it’s a push fit but the original is also crimped into a couple of indents in the aluminium gearbox, making removal more involved.

BILLYWIZ
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Re: Serious gearbox oil leak

Post by BILLYWIZ »

Correct! I had to use a small hack saw and chisel to cut into the side of the seal casing to release it carefully away from the box. It was very tight and access was not easy. Always thinking not to damage the aluminium gear box.
Bill.
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