Oil leak question

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TGJR
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Oil leak question

Post by TGJR »

My 1976 Carrera 3.0 is dripping oil after use from the little hole at the bottom of the bell housing (915 gearbox).

Do I assume this to be the rear main seal? The engine and gearbox have recently been rebuilt.
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911 oil leak.jpg
DustyM
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Re: Oil leak question

Post by DustyM »

Is it gear oil or engine oil?

Another possibility is the oil pressure switch on top of the engine.


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TGJR
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Re: Oil leak question

Post by TGJR »

I am assuming it is engine oil. How do you tell the difference?
Gary71
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Re: Oil leak question

Post by Gary71 »

TGJR wrote:I am assuming it is engine oil. How do you tell the difference?
Smell it. If it’s a bit rancid then its gearbox oil :)
TGJR
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Re: Oil leak question

Post by TGJR »

Fairly sure it is engine oil. Got a nasty feeling it is going to be a costly engine out job to sort..
Gary71
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Re: Oil leak question

Post by Gary71 »

Or just ignore it if it’s not too bad.
I’ve swapped crank seals twice now (whilst the lump was out for other reasons) and it still leaks so there is no guarantee of success.
TGJR
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Re: Oil leak question

Post by TGJR »

If I park up when the engine is hot it leaves an oil puddle about 10cm diameter. Probably only a tablespoon of oil but still...
DustyM
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Re: Oil leak question

Post by DustyM »

That sounds like a lot for a crank seal, I’d investigate further before contemplating an engine out


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Bruce M
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Re: Oil leak question

Post by Bruce M »

Perhaps a problem that should be addressed under the engine rebuild warranty?
christaylorsound
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Re: Oil leak question

Post by christaylorsound »

The old 'triangle of doom' is notorious for oil leaks. I recently replaced my oil pressure switch which was only a few years old as it leaked.... Check the area behind the fan housing thoroughly before doing anything drastic/expensive it's amazing how oil can leak here and be almost invisible! Good luck.
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Re: Oil leak question

Post by TGJR »

Thanks for the replies and suggestions.

The car didn't leak oil for 12 years of ownership and now it piddles out! Modern seals perhaps not as good as they were 45 years ago.
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