Use of Teflon Tape on fuel fittings
Don''t do it!!! I just installed (then re-installed) a complete new fuel system on my 37'' sloop. Everything new, from the deck filler, right through to the lift pump on the 3GM30F, and new return lines as well.
I used teflon tape the first time through, I have some 1 1/2" npt bronze fittings going from the tank through a bulkhead to the fuel hose. Each one leaked just a drop when the system was filled for the first time.
I then had to drain the tank and take everything out, clean it, and re-assemble it all over again. This time I was using Teflon PIPE DOPE/JOINT COMPOUND, and my biggest stilson wrench to ensure that everything would be tight and leak free.
On pipes under 1 1/2", just coat the male threads and sock them down good and tight. On 1 1/2" and up, coat both male and female and tighten well. Be careful to not go overboard using too much pipe dope, as excess will clog up your first filter.