What Tubing for Cockpit Drains ?

[bazzer]

I need to replace my out bad hoses for my cockpit drains. They are 1.5 inch hose. What is the correct hose to use? How many clamps do I need to use on the seacocks that are below the water line?

[GordMay]

I’d use Shields “Vac Extra Heavy Duty”, Series No. 148 or 146
If you have a very difficult (“bendy”) installation, I’d reluctantly use “Vac Standard”, Series No. 140

Shields ➥ Bilge/Livewell | Teleflex Marine
- or -
Trident equivalent ➥ Trident Marine: Bilge, Live Well & Drain

Below waterline hoses require double clamps.
If the barbed fitting is long enough, I’d double all hose clamps.

[estarzinger]

I would use a wire wrapped rubber hose, designated for engine water intake - like Shieldsflex II Marine Water/Exhaust Hose (w/wire) – Series No. 250

The hose Gord recommends above is ok, but is a pvc 'sanitation/freshwater' hose, which I have found can get brittle over time and is more heat sensitive (important if these hoses run anywhere near the engine), and harder to cut accidentally (you really need a hack saw to cut it)

In either case, put double hose clamps on the bottom end. You don't want these coming loose.

[Eric M]

Am I confused or are you saying your cockpit drains are hooked up to below water seacocks? I guess that could work, but it sure seems they would be more free flowing if they exited above the waterline. That is the setup on my current and previous boat.

[GordMay]

Shieldsflex II Marine Water/Exhaust Hose (w/wire) – Series No. 250
➥ Shieldsflex II Marine Water/Exhaust Hose (w/wire)

[boasun]

The Drains should be crossing over. The Port drain, drains out the stbd side of the vessel and visa versa. Some boats the Cockpit drains out the stern. This all depends on the height of the Cockpit deck is above the water line, when the vessel is heeled over to her natural sailing angle. So really making generic comments on how a vessel should drain without the blue prints of said vessel, is hard to do.
But you may also want a check valve in the drain line. To prevent water from flowing into the cockpit.

[bazzer]

Originally Posted by Eric M

Am I confused or are you saying your cockpit drains are hooked up to below water seacocks? I guess that could work, but it sure seems they would be more free flowing if they exited above the waterline. That is the setup on my current and previous boat.

Mine is a 1976 boat, very well built, but the cockpit drains are designed to cross over and exit below the water line via some very substantial bronze seacocks. Whereas the bilge pumps exit above the water line. The old hoses are rubber and definitely need replacement!

[capn_billl]

I would follow estarsinger recommendation, use engine hoses, you don't want these to fail, double clamp anything called bilge, thruhull or drain. if they crossed before cross them again, follow builders design exactly, they had a good reason for the way they did it.

[GordMay]

Originally Posted by boasun

... making generic comments on how a vessel should drain without the blue prints of said vessel, is hard to do.
But you may also want a check valve in the drain line. To prevent water from flowing into the cockpit.

I'd NEVER recommend installing a check valve in a drain line (cockpit, bilge, etc).

[boatman61]

Originally Posted by boasun

But you may also want a check valve in the drain line. To prevent water from flowing into the cockpit.

If that happens.... your probably sinking....

[David M]

Check valves can stick and reduce flow....that is why.

[bazzer]

Check valves are not necessary if the tubing is crossed. In order for water flow backwards into the cockpit the drain will have to be below the waterline. On my boat I would have abandoned ship by this time. I believe ABYC rules are the drains have to be large enough to drain the cockpit in a couple of minutes

[s/v Jedi]

I use corrugated engine exhaust hose. We have 2" drains that exit through the transom, above waterline. When we get big enough seas on the stern, the occasional breaker creates such a back-slap through the system that all kind of stuff comes out these drains, like wine corks etc.

Little crabs live there, until eaten by the ships cats

ciao!
Nick.

[bazzer]

I found some trident-flex 1 1/2 inch hose for $1.50 a foot! Wire reinforced at that. All fitted now and looking good.
Next project is fitting a instant on water heater.