6 replies to this topic

[mike.]

So following on from this topic: http://www.theminifo...p;#entry1166506

I've finally got my car back after them fixing their mistakes.

But they said the new centre plate had no or very very little oil on it and the seal had no oil round it and looked in perfect condition but there was a little oil in the bell housing. Anyway they said they've fitted a new seal and said they rang an old mini specialist they know who said it could be caused by high crankcase pressure.

So they said if the engines got very hot and i was revving the nuts off it (which i was if im honest) and the crankcase breather is blocked then that would explain it.

Is this right? Also i can't see the breather being block because i've got a small breather filter on it and can see the fumes coming out of it when the engines running.

I'll see how it goes anyway and see if this new seal leaks before i bother doing anything. But what could cause high crankcase pressure?

[Guess-Works.com]

But what could cause high crankcase pressure?

worn out engine !

[mike.]

But what could cause high crankcase pressure?

worn out engine !

Can you ellaborate abit? Which bits would be worn out?

[Guess-Works.com]

Generally piston rings and or bores...

Quite simply the combustion is leaking past the rings, increasing crank case pressure, and the 'fumes' you are seeing is the evidence of that...

Run a compression test, and then dribble a little oil through the sparkie hole and repeat the test...

If the compression goes up, your rings are fubar !

[mike.]

DOH! Its just one thing after another with my car at the mo - Getting fed up!

Wouldn't the engine burn oil though if the rings were gone? i.e. Blue smoke from exhaust?

[Ethel]

I'd be of the opinion blaming the leak on crank case pressure is a load of B*!!*x.

The seal is well above the oil level and the centrifuging action of the crank and primary gear will have a far greater effect - if it was down to crankcase pressure it ought to be squirting out of your diveshaft 'n gear selector seals as they are submerged in the sump. You can simply blow down the breather hoses to check if they are blocked.

[GraemeC]

If the seal is new (and fitted properly with the correct tool) then the next probable cause of an oil leak into the flywheel housing is worn primary gear bushes.
After that I would be checking the transfer case a the back of the flyweel housing for hairline cracks.