plumbing

[coolair]

Hey,
just wondering if anyone has used pvc or nylon fitting instead of bronze for like a/c supply line or raw water washdown supply. the damn bronze fittings are so expensive.

[CaptPatrick]

Raw water comes from the sea through a hole in your boat... What keeps the boat from sinking is a valve. When a plastic valve craps out offshore and your boat sinks, how expensive was that bronze valve?

[IRGuy]

Never EVER use plastic through hull fittings!

I owned a Grady White 24 OB for about 10 years. Around the 6th year I had to run some wiring for a new stern light, and while playing upside down in the bilge I happened to look at the base of one of the two baitwells in the aft corners of the cockpit. I did not use the baitwells and never worried about them. I saw that the plastic combination through hull and drain fitting from the stbd baitwell (a 90 degree elbow) seemed out of line. I touched it and it broke off in my hand.. it had cracked completely around it's circumference. I looked at the port side and saw the same thing.. both breaks looked as they had been there for a long time. Both through hull fittings exited the hull exactly in the middle of the boot stripe.. at the waterline.

I had two 1" holes in my boat about an inch or so above the water. I don't think I ever took on water from either one. The water gods had been smiling on me for most likely 6 years. They aren't plastic now!

[coolair]

sorry, need to clarify
i have a bronze thru hull already, but from there to the pump, pump to a/c

[CaptPatrick]

For individual small fittings, like 3/4" NPT to 3/4" hose barb adaptor, you can use Marelon fittings, but I still wouldn't trust PVC. Never use nylon because it'll absorb water and break...

Marelon, (be very sure it's marked as such), is USCG approved. Marelon® is a proprietary formulation of polymar composite compounds using composite reinforced polymer and additives to produce a superior marine-grade product.

In the long run it's still short money to use bronze fittings. Just my opinion...

[Bruce]

I've used plastic fittings many times. But not the thin wall cheap stuff.(read home depot)

If anyone uses the PSS packless glands the water connection is a plastic barb.

The heavey wall black stuff or the heavy wall nylon. Never had one fail yet.

NO PVC

[coolair]

Ya,
I should have made it clear all my thru hulls are bronze, i knew that was gonna start a sh*t storm of respones, haha
Ya the grey PVC is schedual 80, i dont think west marine sales the marelon, they sale nylon

[Rawleigh]

I used PVC to plumb a manifold for my washdown and livewell pumps, but it is located under the gunnel above the waterline. I used bronze and rubber below the waterline.