Drains 101 ...

[TreblePlink]

Originally Posted by Tayana42

Trebleplink, I have a sea chest from one through hull and sea cock supplying my engine raw water, small water maker and salt water foot pump at galley sink. All discharges have separate through hulls and sea cocks. Routing your discharge plumbing to your outboard motor well may bring gray water sludge, fats, food particles as well as bilge detritus to the cooling water intake on you outboard.

Although the 25" outboard's intake is pretty deep, that is a point.


My main cockpit drain seacock is 50 years old, and is a high-quality tapered cone bronze type. I am now servicing it and expect it to be fine.

I just hate the idea of unnecessary hull penetrations. I recently read that the main cause of sinkings according to the insurance industry is thru-hull fittings and hoses failing in one way or another, often at the dock.

I don't really need more than one, if my other outlets route to the transom ...

[alctel]

Why not have your bilge pumps go to an above the waterline throughhull? It will reduce the flow a bit but not by much if it's a decent pump.

That's what all three of mine do, meaning I only have three below-waterline through hulls (engine intake, sink drain and watermaker/washdown pump)

[Kelkara]

Certainly no expert ... but these would be my thoughts if it were my boat.

Originally Posted by TreblePlink

Well, when I remove the now illegal marine toilet, and use a composting head, I go from 4 to 2.

The main cockpit drain is a 1.5" real seacock, and is a vertical hose - it drains well. Then leave it alone and let it do its job if it's already doing it well.

There is a SMALL plastic thru-hull cockpit drain with the outlet so high that is only works when heeled over to one side, I'd like to eliminate that if possible. I can't really visualise this ... is it above waterline? If you leave your boat for a couple of months and it rains a lot ... what happens to the water in the cockpit if the main drain gets plugged? is this a back-up that prevents it downflooding into the cabin?

The current bilge pump squirts straight out at ankle level into the cockpit. There is a minor advantage to this, that while you're out sailing you can easily see if the pump is working and you are taking on water. If your boat doesn't leak then you should rarely get wet toes. But make sure that a flooded cockpit can't back-syphon through this into the bilge. It also probably helps keep the hose run for the pump short which is a good thing.

The current sink drains into the bilge. That's just icky ... I'd be tempted to add an extra seacock for that (is it close enough to the head to repurpose one of those old seacocks? ... or convert to just using a bucket/bowl if you don't actually use the sink much.

And I'd like to add a second, larger, bilge pump. The outlet for this would be best above waterline ...probably out the transom, but into your outboard well might work if the geometry is right.