thru hull fittings

[jetblue319]

anyone knows why the ABYC does not recommend this fitting for below waterline fitting http://www.perko.com/images/catalog/...Fig%200333.jpg

I'm replacing all my bilge pump thru hull fittings with s/s and the below water fittings with the above item along with the scupper item below

http://www.perko.com/images/catalog/...Fig%200285.jpg
thanks
jet

[garagenc]

If their plastic they can break off (under the water line) and flood the boat. I have metal and once a year check them.
P/s use a check valve on the thru hull fitting, I put them on all mine.

[SkunkBoat]

They are the wrong plastic for below water line. You want MARELON.

The first link shows a scupper with a flap which would never be used BELOW the waterline. The second link is a deck drain

Although not the best, it would be reasonable to use the second fitting as your deck drain connected to the first fitting as a thru hull scupper just above the waterline.

[jetblue319]

THANKS, will work on looking for a bronze thru hull fitting.

[Destroyer]

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

[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