I have now removed my gearbox to investigate the cause of my small but annoying oil leak.

There’s a bit of oil across the inside of the bellhousing, so I’ve ordered a seal kit and will to replace all four gearbox seals.

Removing the flywheel, it looks like most of the oil is coming from the bottom of the crankshaft seal or the block/sump joint. The crankshaft seal is mounted into a larger metal plate and the bottom of this plate is flush with the block/sump joint, so it’s difficult to determine whether the oil is coming from behind this or the sump gasket. There is no leak from around the crankshaft itself. I'm not convinced I need to replace this seal but for £20, whilst I can access it, I probably should.

I’ve had the car since it was 4 years old with 25k on the clock, so it’s most likely that the sump has never been off. It looks like it’s stuck on rather than sealed with a gasket. My local factor did not stock a sump gasket and said his system recommended sealant, though this could just be that they no longer list a gasket due to the age of the car. I’ve since found sump gaskets online.

It looks as though the sump could be removed easily enough once the bellhousing is reattached, so I could leave it and see but it would probably be easier to do it now.

Does anyone know if these sumps were stuck on in the factory? I’d be interested in opinions on whether to stick the sump back on with silicone or avoid it if I can get a gasket.

Thanks.