Fuel Tank Access Port Sealant

Oct 18, 2021
J-Boat J/30 Provincetown
What sealant should I use on the threads of the access port of my fuel tank? The tank is aluminum. It has a large threaded aluminum port on the top that has a PVC threaded plug. When the tank is full and the boat heels, fuel slowly seeps out of the port. I was thinking pipe dope or Teflon tape.
Feb 21, 2013
Hunter 46 Point Richmond, CA
Welcome to the forum!!

Suggest a PVC thread sealant compatible with your fuel but check with the manufacturer to confirm compatibility with your fuel (gasoline or diesel) service before you use it.
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Mar 6, 2008
Catalina 1999 C36 MKII #1787 Coyote Point Marina, CA.
I use Rectorseal from Home Depot. Yellow paste good for water or fuel. I called the manufacturer for compatibility with diesel fuel, it is good to use.
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Oct 21, 2009
hunter 38 Monaco
I installed an inspection hatch on my diesel tank. Bought hatch from UK. I met the founder of the company at METS in Amsterdam. He told me that because of all kinds of new chemicals the refiners put in their environmentally friendly fuels they ONLY use cork seals on fuel tanks. But I personally think you could use nitrile rubber without problems.