HELP! Engine oil leak on new engine

Troubleshooting
#1

Hello all my name is Alex
i’m After some help/advice if possible please.

Just rebuilt my ‘93 TT GTO engine, replaced all seals and gaskets using the specified torque and patterns etc. However when the car is running there is an oil leak (see photos)

It’s definitely engine oil but the back of the flywheel and inside the bell housing is completely dry so surely couldn’t be the brand new rear main seal?!

Has anyone else seen this before, it seems to be just on the oil pan but directly below the RMS.

I’ve tried to trace from above but all turbo feeds are fine.

Any help would be great, really don’t want to pull the trans if I can help it :persevere:

It only leaks when the car is running and only a few drips but enough it won’t pass MOT, when the car is off and left overnight not a single drop on the floor

Thanks in advanced
Alex

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#2

Hi Alex
Would I be right in saying that you have used window frame silicone sealant as a gasket rather that RTV silicone?

#3

Nope grey RTV, still have the tube

#4

Had to ask because it looks white in the picture and you wouldn’t have been the first.
The thing is, you are limited to possible answers without taking it apart. I can’t think of many options other than a piece of grit in one of the mating surfaces, oil in a place where there is RTV and it has stopped the silicone sealing properly or a tiny nick or grit in a seal. Maybe someone else will have another idea.

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#5

Well, first things first off with the pan and fingers crossed the above seal looks okay :crossed_fingers::crossed_fingers::crossed_fingers:

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#6

Update:

Removed the pan today and could see where the oil had gotten through some of the RTV, so fingers crossed that’s all it will have been. It was just a bit thin.

Spent the rest of the day scraping off all the old gasket (what a nightmare) and getting the pan back on (also a nightmare on the car just up on jack stands :sob:) also took the opportunity to give the pan a good scrub and paint whilst it was off.

Top tip by the way, I got some old long 10mm bolts and cut the heads off them, put one in each corner of where the pan would line up on the block as a make-shift alignment tool. Worked well so thought I’d share

(needless to say I just removed them afterwards and replaced with the corrects bolts :sweat_smile:

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#7

I always apply RTV in a s way along the sides just to make sure it will make a permanent seal… Have too often seen seals broken when it has been applied only in a straight line

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