Deck flooding

[Todtc]

We had our first good rain here in NorCal last week with several inches of rain falling in just a few hours. My new-to-me 1994 Scout 172 Sportfisher has a new bilge pump set to automatic when I am away. There is a hatch at the stern that is o-ring sealed, effectively keeping deck water from the bilge. I had this hatch closed during the rains and returned to find the transon almost entirely submerged from all the trapped water on ther deck.

Is the proper procedure to open the hatch if rain is forecast to let the deck water drain into the bilge? There is no other way to drain water from the deck unless you are under way and open the self draining scupper(?) ports in the transom. Opening the ports while stopped just lets water in. Am I missing something??

 

[arks]

Re: Deck flooding

Seems to me that you need to add a deck drain- so any accumilating rainwater can get into the bilge.
I guess you could leave the hatch open, BUT will water from the deck just drain naturally into it?

 

[gss036]

Re: Deck flooding

Some thing is wrong if your scuppers let water into the boat. How much water are you talking about? If only a small amount then the scuppers should be left open. Unless you are hooked into shore power to keep the battery charged, you will run the battery dead in short order.

 

[Les Robb]

Re: Deck flooding

Ideally your scuppers should be slightly above the water line. Too close and if you stand in the stern water will come in, too high and the water won't drain. I can't see how the stern could have sunk that low if the scuppers were open. Somethings not right for sure. Why are your scuppers closed? Typically all you would have are flexible flaps covering them on outside to prevent water from rushing in when your in reverse.

 

[EsoxRanger]

Re: Deck flooding

The scuppers on those 176's are pretty darn close to the waterline with a factory rigged Yammi 2 stroke 90 on there. DO you have something even heavier on there?

 

[RWilson2526]

Re: Deck flooding

You almost sunk your boat. although your scuppers may appear to let water in while at rest I would guess it is only a small amount and once you get off the boat or away from the stern I would bet that your scuppers are just a hair above the water line...this lets rain out off the deck.....if your scuppers are below the water line at rest and unloaded do you have an oversized motor on the back or a bracket thats making it sit too low?

If you have a self draining deck (which it sounds like you do) thats the way you want to get rain water out of the boat , not purposely diverting water into the bilge and then relying on the pump....

post up some pics so we can tell for sure. but I would open those scuppers

 

[marine4003]

Re: Deck flooding

Ya,all are missing the point...he has a self draining splash well..like a Whaler it's only supposed to work while underway and the pressure plug has been removed. These are not scuppers..to alleviate deck flood you either need to have scuppers installed slightly above the waterline or install another battery hooked to the bilge pump only, but install it on a selector switch so you can recharge it while running.

 

[gss036]

Re: Deck flooding

My SeaCraft has drains in the motor well and scuppers for the deck. I guess it would all depend on hiw the boat is set up.

 

[EsoxRanger]

Re: Deck flooding

I don't think that boat was made with a splashwell, the transom itself is the back of the cockpit.

 

[Todtc]

Re: Deck flooding

Thanks for all the info...much appreciated. Maybe I am calling the drains scuppers incorrectly. The drains are definately below the waterline with the factory recommended and installed Yamaha 90 2-stroke hanging on the back and standing still. Underway and at speed, the drains are above the waterline and taking out the pressure plugs drains the deck in a heartbeat. The drains are backed on the outside with flimsy rubber-type material that is NOT watertight. Maybe these need to be replaced? I will try to post photos tomorrow.

 

[Bondo]

Re: Deck flooding

The drains are definately below the waterline with the factory recommended and installed Yamaha 90 2-stroke hanging on the back and standing still.

Ayuh,... But How Far,..??

 

[Home Cookin']

Re: Deck flooding

check with the manufacturer (or a dealer) to confirm below-water scuppers. Something is not right. maybe your foam is waterlogged, causing the boat to sit too low.
Even covered scuppers are supposed to drain from water pressure without being under way. I sometimes wonder if my flaps are too stiff to allow this with small amounts of water.
A bilge pump can run continuously overnight and into the next day but I wouldn't test this info!
If your deck hatch kept the water out of the bilge, good; don't alter that. At most, hook up a second pump and float switch in your "cockpit" for overnight heavy rains.
My 17' Key West does not have scuppers and it does have a floor drain, so you have to rely on the bilge pump to evacuate all water. I'm not real happy with that but here we are 20 years later.

 

[scoutabout]

Re: Deck flooding

I'm pretty sure those scuppers should be above waterline (although you don't outright declare they aren't). My local Scout dealer went to some pains to explain that Scout specifically locates the scuppers so that they drain "either while underway or at rest with no passengers on board."

I don't see how they could do that located under the waterline. Certainly mine are just at it and if I pull the plugs some water will start to flow in but not more than a couple of inches worth across the rear of the deck. As advertised, this will indeed drain again if I step out of the boat or get underway.

Also -- don't count on that deck hatch to seal 100 percent. After I bucket down my deck pretty good with water I can count on the bilge pump running a few seconds in addition to the water that goes out the scuppers. One other thing you might want to consider is to change from the flaps to the ball valve type. If you don't mind the quiet rattle of what sounds like a couple of ping pong balls on your boat, I think they may be slightly more effective than the flaps.

 

[gss036]

Re: Deck flooding

Maybe try to go to the ping pong balls, that is what all the new boats are using.
There used to be some type of duck bill drains also. My scuppers are right at the water line since I put on a new 225 Honda, but still allows for drainage.
The old SeaCraft boats had scuppers going out of the bottom of the boat and there is always a lot of discussion on that board about how to fix the scuppers. The site is ClassicSeaCraft.com.
I have to use drain plugs in my engine well now, but have to watch when a 40-50 ft boats come too close in the passes where we fish and try to get my bow pointed toward their wake. Some people just will now slow down. Otherwise I can get a lot of water into the engine well and there is a new deck plate in the well and it it not 100% water tight.

 

[Les Robb]

Re: Deck flooding

Can you redistribute weight towards the bow? If not, unscrew the hatch and viually check the bilge for water and if possible get a piece of foam out for better evaluation. Before you reseal the hatch make sure both surfaces are clean and free of sand dirt etc. Use a light coat of Vaseline on the o-ring to help in sealing.

If set up correctly with plugs out the boat should self drain with no one in it.

My old Mitchell was borderline self draining, if I stood in stern water would come in while in neutral, at the dock (with no one in it) it was fine unless I left the drain plugs in during a real heavy downpour. Almost sank it a coupla times that way.

Luck ya'll