What are Scupper Drains?

[Searay87]

I'm relatively new to boating so sorry for the newb question. I've owned a 1987 17' Sea Ray bowride for the past 3 summers. If has a bilge pump in the engine compartment and a drain plug on the transom.

I just upgraded to a 1987 Sorrento S24. It has 2 bilge pumps. One in the engine compartment and one below the cockpit just ahead of the stairs down into the cuddy. It also has two drains, one on each side near the back not far above the water line. The former owner told me they are scupper drains and he has plugged them. He also told me that they are not legal anymore?? I read the manual cover to cover and couldn't find any information on the scuppers.

What are these things and should they be plugged? What is their purpose?

Thanks!

 

[Huron Angler]

Re: What are Scupper Drains?

Scuppers allow for the deck to drain using gravity, also known as a "self-bailing" hull since the deck is above the waterline and sheds water quickly.

They are great for boats that might take an occasional wave over the bow, rain, or splash that needs to be drained quickly.

The previous owner probably had them plugged since water can also enter the hull thru the same holes, when rocking in waves, etc.

I'm a big fan of scuppers, and I'd use them if I were you. Great way to shed water without draining your batteries.

The bilge pumps are there for lower areas that cannot take advantage of the scuppers.

 

[tpenfield]

Re: What are Scupper Drains?

You can Google that . . .

Anyway, they are holes that drain the water directly over board and not into the bilge. Others may chime in about the USCG regulations on scuppers, bilge draining, etc. I was not paying attention that day in boating class.

 

[Home Cookin']

Re: What are Scupper Drains?

unplug them for safety!
there are flaps you can reinstall to help keep water out, which may occur when several people stand in one corner of the boat. A well-designed boat should not let water in when in normal use.

 

[Summer Fun]

Re: What are Scupper Drains?

+2 on what Huron Angler said.

 

[25thmustang]

Re: What are Scupper Drains?

Not sure how yours may drain, but as stated above some come with a flapper that works to try and keep sea water out, but still allows water to drain. Mine is set up this way, but it seems to be a different set up than most out there.

 

[Silly Seville]

Re: What are Scupper Drains?

Not sure how they can be "illegal" to use since manufacturers are still installing them on new boats.

 

[Richardsix]

Re: What are Scupper Drains?

Got two on my boat, they self drain the deck, do you want a pic of them?

 

[Searay87]

Re: What are Scupper Drains?

http://www.yachtsurvey.com/sinking.htm

Thanks. I did google it and understand their primary purpose. This article seems to suggest that the design of some boats is supsect and offers a test to determine if they should be sealed up.



to Quote the article:
"To check if your cockpit scuppers are safe, first measure the height above the normal water line with tanks full. Subtract 2" if they're near empty. If the height above water is less than 4" you've got a problem. Get three 150 lb. or more persons to stand in one aft corner. Does the cockpit begin to flood with water? If so, your boat is in danger of sinking and you should consider sealing up the scuppers and improving the bilge pump capacity if necessary."

Richard six: Yes a picture of yours would be great. Thanks.

 

[tpenfield]

Re: What are Scupper Drains?

I have wondered why my boat did not have scuppers for drainage. I was thinking of convering my cockpit drains into scuppers. Right now everything drains into the bilge.

After a bit of measuring, I realized that the cockpit floor is too close to the water line, so gravity would not be on my side; it would likely sink the boat.

 

[26aftcab454]

Re: What are Scupper Drains?

May be they were plugged because they drained into the bilge?---My scuppers on the Wellcraft were under a rear bench and would clog with leaves from time to time. The Glastron has them under the Sunpad/engine cover.

 

[Home Cookin']

Re: What are Scupper Drains?

"If the height above water is less than 4" you've got a problem"

I do not agree with this at all.most scuppers and self-baling drain plugs I know are closer to the water line than 4 " and work fine. if some water ships in, it drains back out when you move.
I have heard of some poorly built boats where the scuppers constantly let water in on the deck.

A boat without scuppers originally should not have them added, becuase chances are,the deck is too low.

Blocking the scuppers is how you sink: if you get water in the "cockpit" form a wave or rain storm, it can't drain down to the bilge to get to the pump, so you swamp with a dry bilge and a pump that never got a chance. Blocked scuppers will, however, drip into the crevaces, which can cause more problems than if the water flushes out.

 

[chriscraft254]

Re: What are Scupper Drains?

Ok, some very weird responses here. Scuppers are a plus! Self bailing decks are a plus! Most boats, not all, but most boats with scuppers are self draining. This is a plus as, any water that gets into the boat via water spray, waves, people treading in water, rain etc etc will run out of the boat.

There are some boats made with scuppers that do not drain to the exterior of the boat, they drain to the bilge and rely on the bilge pump to keep the water pumped out. Don't ask me why, It is a very poor design imo.

There are also scuppers/deck drains for self bailing boats that drain to below deck and drain via a hose connection that leads to a thru hull fitting to the exterior of the boat. It all depends on the design of the boat and how the manufacturer desided to plumd the draining.

Op, what kind of scuppers do you have? Are they round, square, oval? Do they have flappers installed in them? Do they drain straight out the back, or do they have drain hoses connected to them to a thru hull fitting? If they go through the deck, check the starboard and port sides for a thru-hul fitting. If any of the fittings are plastic, you should replace them with stainless.

Illegal? I don't think so! Take a couple photos and post them so we can help you better. I would not advize sealing the scuppers unless you have some genious way of evacuating the water that they were put there for. .

Some scuppers on say an older mako that is water logged might be even with the water. As long as they are above the water and have splash gaurds/flappers they are good to go and will still do there job of draining interior water to the outside.

 

[Richardsix]

Re: What are Scupper Drains?

Not the best of pics.View attachment 122219View attachment 122220
Hole in bottom is where I remove the screw in bung for the winter.

 

[Bob Hamilton]

Re: What are Scupper Drains?

I'm a newbie with a used Alumacraft. My bilge pump hasn't been working and I've been having a lot of water entering the boat. I have an opening drain (?) under the waterline on the transom next to the drain plug. What is this opening? I have another opening on the side of the boat that must be a scupper. I've found out the bilge pump had a blow fuse, but the pump would work non-stop removing water that is coming from the opening next to the drain plug. Can someone please enlighten me on how to repair this problem. I'm attaching pics.

 

[louiefl]

Re: What are Scupper Drains?

The first pic looks like the intake for some sort of live well pump or wash down. There should be a valve on the inside immediately where it passes through the transom. If it is leaking where it passes through, check to see if there is a hose attached to it inside the bilge. If the hose and clamp are ok, check to see if it is loose or has any visible gaps. It may need to be removed and rebed with 5200.

Never seen a screen on the outlet of a scupper to drain the deck, so pretty sure this is an intake screen. The second picture thru hull fitting is a discharge for either a self draining live well, or a pump out for a live well, fish box, or bilge. This is likely well above the water line and should not be underwater.

You'll probably get fussed at for not posting a new thread instead of hijacking an old one, but felt like be in a giving mood this morning. Good luck and report back.

 

[durban]

Re: What are Scupper Drains?

iam all for scuppers , any boat with a deck below waterline relying on a bilge pump should something go wrong is a bucket in water filling up following the law of gravity .