Ok thanks. Do you know if it is the normal practice to just assemble it with only the rubber gasket and no RTV or sealer of any sort?

My old tank and sender had some sort of goop slathered all over it at some point. It was all hardened and had run down the side of the tank. But it was a sealent of some sort.

What did they do from the factory???

What should I do to make keep it from possibly leaking?

When I did a simple presure test with my mouth blowing air into the filler vent tube and holding a finger over the filler tube and over the sender tube it seemed to hold pressure fine. Well like a couple minutes and then my mouth and tongue got tired! Then it al blew out when I released.

And if I do the same on the gas cap it seems to vent at a lower presure than that so I would think it would not leak unless the pressure got really high really fast and the cap could not release it.

Thoughts??