Author Topic: Oil seal, Bummer!!  (Read 494 times)

Offline Tone

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Oil seal, Bummer!!
« on: 17.04. 2016 18:29 »
After a lot of fighting finally got the engine out , gearbox off, new oil seal on, all back together, guess what, new oil seal leaks!!! BUM  *problem*

Offline muskrat

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Re: Oil seal, Bummer!!
« Reply #1 on: 17.04. 2016 19:14 »
G'day Tone.
Are you sure it's the seal? They can also leak between the countershaft (the part the sprocket goes on) and mainshaft (goes through to the clutch). The seal will leek onto the inside of the sprocket, the other on the outside.
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Offline Tone

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Re: Oil seal, Bummer!!
« Reply #2 on: 17.04. 2016 19:24 »
I've wiped it off, and it seems to dribble from the seal, because it runs down the side of the case ( under the seal area) around under the box and drips off the drain plug. Does that show its more the seal or the shaft. Any ideas?

Online morris

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Re: Oil seal, Bummer!!
« Reply #3 on: 17.04. 2016 21:39 »
I've always found it a curious design, relying on the clip to exercise enough pressure on seal and bearing to keep the joint oiltight.
The seal should be well centred and pushed firmly against the bearing.
That said, there's a lot of different quality seals on the market. Some are good, others are less good in that area.
I once replaced a new seal because it leaked around the outer edge.
Overfilling the box can also make them leak, but this will usually be via the mainshaft.
You could try with a smear of sealing compound around the outer edge.
Or install a sealed bearing.
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Offline jjbsa

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Re: Oil seal, Bummer!!
« Reply #4 on: 22.06. 2016 21:22 »
I've been told that some people who raced Goldies used to fit gearbox breathers to stop oil coming down the clutch pushrod into the back of the clutch.  Anyone tried this?