thru hull fittings

[SkunkBoat]

Originally Posted by Destroyer

NEVER have ANYTHING other than Brass, Bronze or SS under the water line as a thru-hull. Period. My personal choice is SS.

never use BRASS in ANY fitting that makes contact with seawater, ever. It contains copper and zinc and zinc "disappears" in salt water, weakening the brass.
Also, never use a Brass fitting on aluminum (such as fuel tank) because of bi-metallic corrosion.

Bronze contains copper and nickel and does not have the same problem, provided that you bond them in common with all other submerged metal( the motor and all other fittings). SS also needs to be bonded.

A big PRO for using MARELON is not needing to maintain a good electrical bond