Outboard motors use rubber o-rings where the gas and oil lines attach to the engine. (I have had to replace them) So there are gas resistant o-rings (possibly neoprene?) out there.

If you have a friend with a lathe, you can make almost any size ring you want. I made some Delrin bushings on a friend's lathe.


Gord 🇨🇦
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1954 1/2 ton 235 4 speed