Sink Drain Thru Hull

[KWKloeber]

What are y'all needing?  Thread and hose sizes.
You have to be very careful with forespar fittings and whether they are NPS or NPT thread and female going to male and vice versa. One way they can work, the other way it can be disastrous.

[Oldlaxer1]

I'm good Ken.  Turns out mine is 3/4 thread and I'm using 3/4 hose so a straight Marelon tailpipe works for me.  Part #905007   It's cheap enough that I can buy at my local WM and not have to cry...
Question though, should I use ptfe thread tape on it?  I'm never sure with Marelon.  Here is their newest catalog. see page 9 for the fittings available.

[Ron Hill]

Guys : I kept the redo plumbing under the sink high near the sink and went straight over to an elbow and a 1" hose that went straight down to the sink thru hull.  Was easy to fit the 1" hose on to the 3/4" barb on the TH.

That high plumbing left more room below for my enlarged drawer (see my Mainsheet tech note article). The drawer is deep enough to hold a nest of pot/pans!!

A thought

[KWKloeber]

I'm good Ken.  Turns out mine is 3/4 thread and I'm using 3/4 hose so a straight Marelon tailpipe works for me.  Part #905007   It's cheap enough that I can buy at my local WM and not have to cry...
Question though, should I use ptfe thread tape on it?  I'm never sure with Marelon.  Here is their newest catalog. see page 9 for the fittings available.

I'm not sure about yours or the C34 in general but of course the problem caused by using an adapter fitting that is the same size as a discharge hose, is that it creates a significant restriction.  If you need a 3/4" flow, it's better to oversize the hose and adapter - that way the thru hole remains at 3/4" (naturally you still have to deal with the valve restriction.)  IIRC the best adapter is a 1" hose to 3/4" thread.

As far as a NPS threaded tailpiece, yes use tape - since it's a straight thread (not NPT) there's no way to really tighten it. Multiple layers of tape help immensely.  I'd use the HD (gray) thread tape. It's MUCH beefier than the typical white ptfe.

[waughoo]

Ken

I'll be at the boat again this coming weekend and can see what I need.  If possible the same 90 fitting would work best for me as I want to maintain the general route of the drain as it is, but improve it such that it can't kink or bend.

[KWKloeber]

Would it be practical to route the hose in a gentle bend (rather than a sharp 90 adapter) and use a straight thru adapter?

[waughoo]

Possibly.... I'll need to look at it again with a bit more detail towards routing.  I'll be up there this weekend and can look again.

[Ron Hill]

Alex : I mentioned, keep your new piping/hoses as close to the bottom of the sinks as possible.  That way you can make use of the room below.
 
I had no problem with the 90 degree elbow, because the PVC piping was 1" and it is amazing now how the sinks drain in a few seconds!!

A thought

[Oldlaxer1]

So Ron, am I reading correctly that you put a 1" hose on the 3/4 barb at the through hull?

[waughoo]

Alex : I mentioned, keep your new piping/hoses as close to the bottom of the sinks as possible.  That way you can make use of the room below.

I have the fancy new drain fittings that allow for keeping the hoses rather tight to the bottom of the sink basin.  It should allow for some more clearance in there.

[Ron Hill]

John : You are correct!!  There is no pressure or suction - just a gravity feed.  The 1" hose neatly clamps on to the 3/4" barb.

It is just like the 5/8" raw water hose clamping on to the 1/2" thru hull!!

A few thoughts

[KWKloeber]

Why use 3/4" instead of 1" on a 1" hose????

[Ron Hill]

Ken : The 3/4" barb is already on the TH, it's below the waterline and the sink drains marvelously - so why change it ????

A thought

[Joesboat]

This thread covers just what I am searching for. Thank you for sharing the knowledge.
I tried to message KWKloeber Ken regarding purchasing a fitting from him but the DM was blocked, I wonder if it is because I'm new or something else?
Any suggestions? Ken?

Thanks again.

C34 #444

[KWKloeber]

PMs are a PITA. Use the email link that's right there as well!