oil leak - any common areas to look at please?

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orangecurry
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Mon Aug 03, 2020 7:49 pm

So I have an oil leak. It isn't from the gearbox, as I have just drained 1.25 from it and put lovely new Fuchs in.

It drips from the low point on the bellhousing, so it could be originating from anywhere.

...but if leaking down to this point from up above, it is coming from the direction indicated by the arrow, as it seems totally dry above the other side, and oily on this side.

Any clues for a common cause please? I know it could be coming from anywhere, and it's difficult to clean the engine above this area.

It's not the oil filter.

Thanks.
oil-drip.jpg
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Brianmoooore
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Mon Aug 03, 2020 11:43 pm

Rear of engine sump gasket probably.
The alloy plate occupying most of your pic. is just a cover/strengthening plate, and is held in place by the five bolts you can see in the pic., plus the one just missing off of the top. Once it's off you will see a few bolts securing the back of the sump, and they will probably be not particularly tight.
If you're lucky, tightening them will fix the problem, but there's a good chance the sump gasket has failed.
That's also the place that clutch fluid drips from when the slave cylinder is failing. Taste test will determine which.
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orangecurry
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Tue Aug 04, 2020 7:21 am

Yum.

Thanks Brian.
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orangecurry
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Tue Aug 04, 2020 7:44 am

oh... what is the torque for those bolts please?

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BristolE30
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Tue Aug 04, 2020 8:16 am

orangecurry wrote:
Tue Aug 04, 2020 7:44 am
oh... what is the torque for those bolts please?

Thanks! :D
Too me that’s looks exactly like a clutch slave cyl leak. Happened to mine a few weeks ago and dripped from this spot. Slave is quite easy to remove to check? Just two bolts and off she comes. Oh and also the line for it
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Tue Aug 04, 2020 8:51 am

undo the 8 bolts (4 hex head 3 torx head)

remove that plate & check how tight all the bolts are underneath it,

but as Brian says the sump gasket could've failed as that's a pretty common failure.

9 times out of 10 the gasket fails on the rear most bolts on the drivers side,
i had one like that a while back & i was able to drop the sump just a little, & pushed the gasket back into place & used a little RTV sealant to keep it place,

never had a leak since.

also what doesn't help is that the 2 bolts right at the back are head to get to straight on, i use a couple of wobble extension bars so i can get them done up good & tight.
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
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orangecurry
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Tue Aug 04, 2020 10:17 am

:thumb: thanks all - will have a look at all of the above
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