So, it sounds like it's the gasket that isn't working. They have to be the right size because there is some pressure in that canister.
Don't need another - got about four in the cabinet - all Purolators - all L20051.
The gasket has to be the right size or it will not work. I ran into that myself.
Make a gasket out of heavy gasket paper so it is thick enough to "crush" when lid is tightened. Maybe that will work.
