Why are my cockpit drains run like this and can I change them ?

[OldManMirage]

On my Endeavour 32 the cockpit drains are at the aft end and the drain lines run forward to separate through-hulls down alongside the engine. Strangely they are both on the same side of the engine, and they are one behind the other. The hose runs themselves are really in the way of my already poor access to things there.

They are small drains that I would like to upgrade to at least 1.5 inch. And I would like to shorten the run if possible.

Is there a reason they are run to this "low" point ? Can I simply run them aft to my transom ? I have bilge pump outlets just under my transom at the stern, which is above water level when the boat is sitting normally.

Is there some dynamic here I am unaware of ? As long as the runs are "downhill" the water should drain, yes ? Or would a sailboats normal heeling affect this too much ?

[OldManMirage]

Here is a pic of the stern, you can see the bilge pump through hulls. I have good access and could mount drains anywhere in the area. Is there a reason not to ?

[GordMay]

How high is your cockpit deck, above the waterline?

[tkeithlu]

Does the lee edge of the cockpit go below the waterline, or below the waves line, on a heel? If it does, then you need to take in the possibility of water coming into the cockpit from below. One way to deal with that is putting stop valves in the hoses, where they may leak during a long tack. Another is crossing the hoses side to side, so that if the corner of the cockpit is under water the outlet is above water, and none comes in backwards.

Think through the geometry of water flow at all degrees of heel. Then go for it.

Nice boat.

[Tetepare]

I’m not a fan of making more holes in a hull, so speaking for myself I’d study long and hard why the designer did what they did. And, I’d prefer to reroute the hoses or some other solution before cutting holes.

It is a nice boat, well designed. Which makes me question why they’d have designed the drains like that- in fact since it’s such a good design it makes me believe they did it that way for a reason- a warning not to mess with it. Of course, all that could be wrong too.

[OS2Dude]

Since they are gravity feed, the thru-hulls for the cockpit drains must be below the level of the drains themselves. If you add new drain thru-hulls, be sure the hoses are in an accessible place. They will need to be inspected. If at all possible, have the thru-hulls above the mean waterline. Since they typically do not have seacocks, you would not want to sink your vessel if a hose came off/broke.

[Telemark43]

Originally Posted by OS2Dude

Since they are gravity feed, the thru-hulls for the cockpit drains must be below the level of the drains themselves. If you add new drain thru-hulls, be sure the hoses are in an accessible place. They will need to be inspected. If at all possible, have the thru-hulls above the mean waterline. Since they typically do not have seacocks, you would not want to sink your vessel if a hose came off/broke.

Need seacocks at thru hulls.
Do not used one way valves.
Run drains to opposite side of hull
to help with following seas...
reminder following seas can be
much higher that static height above
normal waterline...

[OldManMirage]

Some of these are the same questions I have. A Couple of points...

The drains do not now run to opposite sides of the hull. They run down along one side of the engine - starboard - and the thru-hulls are one in front of the other.

The cockpit floor is about a foot above the static waterline.

I have good access to the hull below the drains and I believe I could easily cross the lines to opposite sides with room for seacocks. The position would be aft of where they are now, by several feet, but still below the waterline.

I guess one question that comes to mind is why are these run so low in the hull. I've come across multiple ways boat builders do this. Some are low, some are not.

If its below the waterline wouldn't it always have water in it up to whatever the static water level would be at that moment ?
So any drain water would have to offset that in order to drain. Correct ?
So what is the point of putting them any lower than the amount needed for them to drain at all ?

I could, in fact, using a 90 degree elbow from the cockpit drain run them right out the transom at a sufficient angle for drainage. That would seem to be similar to walk-through transoms, at least in theory. Of course reality is it wouldn't drain at all as quickly of course.

Essentially I'm trying to gain better access to a critical area by getting the hoses out of the way. If I were to relocate the thru-hulls I would fill in the old ones.

[capt jgw]

Down next to the engine is maybe two or three feet below water line? Considerable back pressure down there slowing the flow, and more hose to collect gunk and clog. All my boats had the drains terminate at or slightly above the waterline and only a few inches of hose, that gives the fastest flow. But as said earlier, the designer and builder must have had a reason for doing what they did, it likely was not the cheapest option. Whether that reason makes any difference is another matter. If it were my boat I'd probably move the drains and glass over the old holes.

[wheelerwbrian]

I’d check with the owners group to see what others might have done.
Endeavour Owners Group

[Stu Jackson]

Originally Posted by OldManMirage

Here is a pic of the stern, you can see the bilge pump through hulls. I have good access and could mount drains anywhere in the area. Is there a reason not to ?

That's where my cockpit drains are, too. I could cross them but never have, owned this boat for 25 years. Sometimes when going aggressively upwind one backs up, not a big issue normally.

[MJH]

Originally Posted by OldManMirage

On my Endeavour 32 the cockpit drains are at the aft end and the drain lines run forward to separate through-hulls down alongside the engine. Strangely they are both on the same side of the engine, and they are one behind the other. The hose runs themselves are really in the way of my already poor access to things there.

They are small drains that I would like to upgrade to at least 1.5 inch. And I would like to shorten the run if possible.

Is there a reason they are run to this "low" point ? Can I simply run them aft to my transom ? I have bilge pump outlets just under my transom at the stern, which is above water level when the boat is sitting normally.

Is there some dynamic here I am unaware of ? As long as the runs are "downhill" the water should drain, yes ? Or would a sailboats normal heeling affect this too much ?

They sound weirdly placed...maybe a new workman on his first day on the job. I'm curious, what issues have you experienced with this arrangement? What did your surveyor say during the purchase?

As the scuppers are at the aft end of the cockpit corners the hoses should have crossed and then exit the hull (not transom) via thru-hulls with seacocks in the vicinity below the waterline.

The correction, during your next haul, will be involved with plugging the old holes and drilling new ones with possible hose replacement.

~ ~ _/) ~ ~ MJH

[Scorpius]

Originally Posted by OldManMirage

Some of these are the same questions I have. A Couple of points...

The drains do not now run to opposite sides of the hull. They run down along one side of the engine - starboard - and the thru-hulls are one in front of the other.

The cockpit floor is about a foot above the static waterline.

I have good access to the hull below the drains and I believe I could easily cross the lines to opposite sides with room for seacocks. The position would be aft of where they are now, by several feet, but still below the waterline.

I guess one question that comes to mind is why are these run so low in the hull. I've come across multiple ways boat builders do this. Some are low, some are not.

If its below the waterline wouldn't it always have water in it up to whatever the static water level would be at that moment ?
So any drain water would have to offset that in order to drain. Correct ?
So what is the point of putting them any lower than the amount needed for them to drain at all ?

I could, in fact, using a 90 degree elbow from the cockpit drain run them right out the transom at a sufficient angle for drainage. That would seem to be similar to walk-through transoms, at least in theory. Of course reality is it wouldn't drain at all as quickly of course.

Essentially I'm trying to gain better access to a critical area by getting the hoses out of the way. If I were to relocate the thru-hulls I would fill in the old ones.

If you run them to the transom, when a following wave breaks against your transom you will get a geyser up your pant leg from your cockpit drain(s). On lots of boats they are crossed to the opposite hull side but you have to be careful to make sure that the geometry is such that the low side cockpit drain will drain downhill when the boat is well heeled.

On Scorpius the cockpit drains go straight down and the cockpit floor is only a few inches above the waterline so I regularly get a bit of water in the cockpit. Who cares. I don't.

All through-hulls should have seacocks. Don't use stop- or check- valves. Particularly in salt water they gum up with growth and stick. And if they stick closed your cockpit won't drain. A boat recently sank at the dock here when a snowstorm that dumped about a foot was followed by a heavy rain that saturated the snow (REALLY heavy) and filled the cockpit that didn't drain. Next day the boat was completely flooded and hanging by it's mooring lines.

[jmschmidt]

I have four cockpit drains (Newport 41 with separate helming cockpit) which feed into two thru hulls well below the waterline. Water pressure inside such thru hulls will remain relatively equal with little change due to sea state. This helps to prevent any blow-back. A flowing sea tends to force water into and up transom mounted or under transom mounted thru hulls.

Boats with open transoms can drain the cockpit without any fixed drains but are at the mercy of a following sea. Closed cockpits should have the drain openings on the cockpit floor a couple of feet above the waterline. I forget the exact height...28"...Something like that?

[onavegador]

as mentioned by tkeithlu it may be that the through hulls at the end are prone to fill from the hull wave if sailing at some speed. The through hulls of the bilge pump may be closed by the diaphragm of the bilge pump. Please let us know what you will doing and the result.

Good luck and thank you.