Is Loctite 545 acceptable for..
 

using on the pipe threads of fuel lines?

It appears the factory used it on the screws holding in the sending unit on the top of the tanks. I want to use it where the AN/pipe thread adaptor will thread into the top of the tank.

Re: Is Loctite 545 acceptable for..
 

I would use the Loctite 55 if you want to use the Loctite product line.
http://65.213.72.112/tds5/docs/LOC55PSC-EN.pdf

I use a product named Gasoil Thread Sealant.