Please explain self bailing for me

[scottstef]

I recently picked up a 1971 O’Day javelin. Can someone please explain how the self bailing works and what plugs I need? In the cockpit is a drain that drains straight through the bottom of the hull. When the boat is in the water without a plug in the cockpit it fills the cockpit with eater. There is also a drain in the transom that will fill the bulge with water if it is not plugged.

my question is if both of these holes should be plugged or to keep water out? How does the self bailing work if they are plugged?

I wouldappreciate any guidance because I am wondering how I can leave the boat in a slip without it sinking.
Attached are picks of the drains. Thanks in advance.

 

[Calif. Ted]

Self bailers usually have some sort of rubber one way valve involved, either an internal flapper or external duck bill. They prevent water entering when the boat is stopped and allow it to drain when moving.
Sea-Dog Line Thru-Hull w/Scupper
TH Marine Supplies Duckbill Scupper

 

[shemandr]

You need a few removable plugs like for a sink at home. You'll have to learn to live with the fear when it rains that you'll find your boat swamped.
I had bailers in my Bandit 15. They worked pretty well when the boat was moving smartly. The suction created by the water passing the hole sucks out incidental water from spray or whatever. Mine had a closure mechanism which only worked so -so. I dragged that boat up on a beach to empty the water more times than I'd like to think about.
Finally after Hurricane Bob stove the hull in on the trailer, I glassed over the holes and never looked back. There are all kinds of plastic bottles that can be formed into bailers.

 

[shemandr]

This is more like what I had:

Automatic Bailers | West Marine

Check out our Automatic Bailers and more from West Marine!

www.westmarine.com

 

[kloudie1]

That drain in the bottom should have a little floaty ball in it that would stop water from entering at rest but open when underway to let water drain out of the boat.. It is not as "floaty as a hollow ball but an elastomer ball that is just a bit positively buoyant.. I have no idea who made those or if the ball is available..
EDIT: These are kinda "iffy" and always should be plugged if the boat is going to be in the water for a while unattended.

 

[scottstef]

So can I simply cut a hole in the cockpit deck large enough to put an 8” cover plate on it and a put a bilge pump in it? If I do that I can put a drain hole in the cockpit deck and then just drain all water into bilge and have it pump itself out when it gets full.

 

[Cole07]

So can I simply cut a hole in the cockpit deck large enough to put an 8” cover plate on it and a put a bilge pump in it? If I do that I can put a drain hole in the cockpit deck and then just drain all water into bilge and have it pump itself out when it gets full.

I don't see how this would create any problems as long as you have a reliable power system. On my very similar O'day Daysailer, I don't even have a self bailer or anything like it. The previous owner used one of those compression plugs in place of where the self bailer should go, but the metal lever piece in the center came out and the rubber piece got stuck. When I got it there was just a hole about 5/16 inch wide in the back of the boat. I could've removed the old rubber piece and bought a new self bailer, but I decided to just shove a random bolt that was a little wider to make a friction fit as a "temporary fix." I ended up just keeping it in and it worked great. However, I trailer my boat so I don't really have to worry about it filling with water in a slip.

 

[Hunter216]

I recently picked up a 1971 O’Day javelin. Can someone please explain how the self bailing works and what plugs I need? In the cockpit is a drain that drains straight through the bottom of the hull. When the boat is in the water without a plug in the cockpit it fills the cockpit with eater. There is also a drain in the transom that will fill the bulge with water if it is not plugged.

my question is if both of these holes should be plugged or to keep water out? How does the self bailing work if they are plugged?

I wouldappreciate any guidance because I am wondering how I can leave the boat in a slip without it sinking.
Attached are picks of the drains. Thanks in advance.

Welcome to SBO
I’m not sure if you already have this but thought it might be useful.

If you plan on leaving the boat in the water unattended you might want to consider some type of cockpit cover to shed rain.

Note self bailing isn’t self draining. I think your boat is equipped with a drain so after you put it on a trailer or beach etc. you can pull the “stopper” and let any water out. The other drain in theory let’s you get water out of the boat if you are moving through the water fast enough for it to work. Kinda dicey as if you stop moving there is potential for water to come in!

As mentioned above you can make a “bailer” out of a plastic bottle. My favourite is the semi transparent quart milk jug with the handle. Just cut the top section of, tie a light line on it as a lanyard (yes I’ve thrown a few of these overboard )

Self draining is different in that it works when the water in the boat is above the water line. IE floor of the cockpit where the water accumulates can flow out via gravity via a thru-hull or in the case of my boat through the centreboard slot. Some boats have an open transom that’s lets the water out that way

 

[Sunbird22358]

That Self-Bailer is the older "DePersia" Brand unit, also used on that vintage DS II. Newer boats have a plastic version that is basically the same as the one used on the SUNFISH. The drainplug in the transom is used to drain any bilgewater after boat is hauled out and MUST be plugged while boat is in the water. Replacement drainplugs with the flange can be purchased at most good marine stores or maybe better yet, at D&R Marine www.drmarine.com D&R is owned and run by Rudy Nickerson who was the Parts Dept. Manager for O'DAY from 1973-89. He now sells replacement part for our boats. The DePersia bailer originally had a screw-in plug to seal it when you don't want water to come in, but those were often lost on older boats. Based on my DS II, you can leave the plug out of that and only about a gallon or so water will come in at rest with no one aboard, and any rain water will easily drain out. While sailing, the bailer will suck water out due to suction formed by the water flowing past the scoop under the boat. I have the newer plastic bailer fitting and leave it open while moored and insert a rubber stopper into the top hole while sailing to stop water from coming in. There should be 2 plastic inspection ports in the cockpit sole (floor) located near the forward end of the cockpit, those can be used to access the CB pivot bolt, but also to bail out any bilge water that may collect while boat is in water. You can use a sponge to bail or insert a typical tube-type bilge pump (they look kind of like an old-fashioned bicycle tire air pump). I happen to have a good diagram of how that bailer is supposed to work and have attached it. I wil lalso attach a picture of the newer plastic one, D&R sells those, but not cheap! (around $50).

 

[dpekala79]

Have you ever seen or know where I can get a replacement drain plug like what’s in the pic? I rebuilt my self bailer with a custom cut washer and a replacement ball and seal for a sunfish and it works. Just want to get the boat to 100% for some reason.

 

[Justin_NSA]

Self bailing illustrated