ET: Engine (Twin) Oil Leak

nigsey

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Not sure if it's one of the studs I am thinking about, But just to show you the recess in the primary side,
There is a nut brazed onto the end of the long studs,
This is a photo from Robert USA,
I would try and seal it from the outside if you are sure where it is coming from,
But Vincents are known for oil leaks coming from far away from what we think !!.
I’m with you now, will see how it goes. About an egg cup full of oil leaked out in quite a short time of running it up, I must admit it made me feel a bit sick (with worry).
 

nigsey

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At the risk of starting an international incident That would be me.

Robert - from the west coast of Canada ---- Canada. To be fair I only live 8 miles north of the 49th Parallel but the border has been closed for several months so it doesn't even count as close!

Loke others I would say an overfilled gearbox and oil getting past the seal or in between the main and output shafts.
I hope it’s something as simple as that Robert. I liken Vincent ownership to having a child, worrying about them all the time.
 

Michael Vane-Hunt

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At the risk of starting an international incident That would be me.

Robert - from the west coast of Canada ---- Canada. To be fair I only live 8 miles north of the 49th Parallel but the border has been closed for several months so it doesn't even count as close!

Loke others I would say an overfilled gearbox and oil getting past the seal or in between the main and output shafts.
Pacific South West. Please.
 

nigsey

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Checked the gear box oil level this morning and it’s very high, just beyond the top of the flat on the dipstick. Now I had checked this several times since I bought the bike and it has only ever been just showing on the bottom of the flat, the other thing is that the oil is a reddish brown colour now when it was clear before. I have neither changed the oil nor topped it up since I’ve had the bike, the only thing I’ve done is add oil (to the correct level) in the primary case which appeared virtually empty when I got it. In which case, has the oil I added to the primary found its way into the gearbox?
 

Peter Holmes

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Reddish brown sounds a bit like rust contamination, not totally unheard of in the primary chain case due to condensation. There is a long explanation of this phenomenon on this forum somewhere, I would search Hugo Myatt, basically the engine can pressurise the chain case through the main bearing, and the pressure in the chain case forces oil into the gearbox, I am not for one minute saying this a definitive explanation of your problem, but perhaps something you should consider, if that does prove to be the problem, I have to tell you there is no quick fix.
 
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vibrac

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Peter is probably right about the source if it was clean or black its not unknown to come direct from the engine I dont think its a cue 1960 gearbox breathers but like the twin racer with a belt dry chain case a seal behind the output sprocket is a solution
 

greg brillus

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If the oil leaking out is similar to the colour of the oil in the gearbox, it could likely be the output shaft bushes have collapsed, thus the red/gold tinge coloring of the oil........not an uncommon problem, and not too difficult to repair, if not messy.
 

Peter Holmes

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Gregs suggestion is a good one, I have had this happen myself, but you can normally see the small glittering particles of bronze, or whatever it is in the oil, it looks like liquid metallic paint, and would collapsed bushes lead to unexplained excess oil in the gearbox that wasn't there previously, that oil had to come from somewhere.
 
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