New out of box MANN oil pan gasket sipping

[500AMM]

As part of preparing my ex. Limited for handover last year I did a transmission oil & filter change. The oil pan was freshed up with a respray due to regular wear and some scratches at the bottom, but no dents. I checked the pan was 100% straight and used a MANN filter kit, but the gasket didn't seal properly and it was even on cold engine before start up. Took it down and checked if something had happened during install, but everything was fine. Put it back and tightened a little bit more, but still sipping, quite a lot in fact.

The MANN gasket fit fine on the oil pan and kept the profile during tightening. I compared to the original gasket and it is a bit higher and wider, but the main difference is the flexibility, it has a significantly harder rubber compound. So I ended up putting back the original gasket, tightened up and all good. Has anyone else experienced something like this?

 

[gsxr]

I haven't experienced this, however I have only used OE/Genuine Mercedes pan gaskets due to the relatively low cost (well under $10 USD each on this side of the pond). If the Mann gasket doesn't work well, that's depressing.

 

[500AMM]

A genuine gasket cost no less than 18 times more here in Morepay!...yes you read it correctly 18 x $10 USD = $180 USD!! While the oil filter is about $100 USD. I shopped at AUTODOC this time, an huge aftermarket vendor here in Europe with nice prices and a wide product range from URO garbage to reputable brands.

As known the oil pan bolt torque is quite low and has to be applied evenly, and any overtightening will give deformation of the pan causing leaks. I'don't have a torque tool but wrenching on motorbikes, outboards etc.. has given a good feeling though, so I was pretty close to max torque by watching the pan. The MANN products are considered good but this gasket is simply to hard. Maybe a tiny string of sealant would be a proper fix, but transmission oil filter change is a repeatable maintenance point, so adding sealant requires a cleaning job every time.

However, I have been using the following trick sometimes;
- fix the gasket on the oil pan in this case.
- apply an even string of sealant on the gasket surface - plus a separate 30-40 mm string on a piece of cardboard etc...
- don't smear the sealant out, but leave it as a string.
- let it cure for some minutes until it doesn't stick - which is checked by touching that separate string.
- apply some grease or oil on the other sealing surface and wipe off with your finger only, leaving a tiny oil film on the surface.

When installing the part the string of sealant will squeeze out but still have enough flexibility to do the job - but without permanent adhesion to the mating surface. Works fine on non-pressurized connections, but use a sealant with high temp properties.