kontiki wrote:

When I put a new fuel cell in my airplane last year it came with all
the gaskets including the sender gasket. It was cork and I used a light
coat of Vaseline only.

The gaskets are rubber. When I opened the wing bay at annual this year,
the leak was obvious. Three years ago when the senders were replaced,
we put new gaskets in with a thin film of "FuelLube". They leaked just
enough to stain the fuel tank and put a fuel smell into the cockpit and
hangar. The gaskets have developed cracks around the screw holes,
probably because the screws were overtightened, so they must be
replaced. I dont want to be doing this again...