help please ! what causes water to leak into the hull

bicyclejuju1 · 07 June 2012, 01:41

I just bought my first boat. Its a 2001 west marine 310 by Avon rib. I got the holes patched up and gave the Johnson 9.9 motor a tune. My question is the water in my Hull. I tried what I read to do "bathtub test" it. I filled the inside of the boat with water. I let it set for about half an hour. I pulled the upper plug to drain it. After it was empty I undid the lower Hull drain plug I got about about a gallon of water out. What is the best place to start to figure out a fix. The deck looks in good condition w no damage or holes. That makes me think the water is getting thru along the seams where the rubber meet the fiberglass. How do i seal this exchange of water? Is it normal to get water in between the deck and Hull? If not what's the drain plug for?

bicyclejuju1 · 07 June 2012, 02:52

Here she is

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9D280 · 07 June 2012, 07:38

The bung is to do exactly what you just did - drain the cavity. The leak may actually be the bung! You might be surprised just how not waterproof some of these bungs can be!

A trick I used on my old laser (and on the rib) is to coat the thread / seal area (depending on your bung design) with petroleum jelly. (think of it like a non setting liquid gasket) - it works wonders to seal bungs and threads on access hatches!

Only thing is you need to remember to clean & re- coat it every so often, as it will eventually dry out.

gotchiguy · 07 June 2012, 11:59

Quote:

Originally Posted by 9D280

petroleum jelly.

I didn't realise you worked for the BBC?

9D280 · 07 June 2012, 12:15

Sorry - spent too long round your corner of the world having to pretend I worked for them so anyone could understand me......

Slap yer missis' vas oanit.

viking61 · 07 June 2012, 12:38

easy check :- if boat on a trailer , first thing in the morning b4 sun gets hot put bung in as hard as you can with a bit of grease or vaseline to help it seal and wait for temp to rise , when warmer release bung , there should be a small whoosh as the air in the void escapes having expanded with the warmth. if no whoosh then there is a leak elsewhere. Clean bung off before going to sea ! Now imgagine the process in reverse , put warm boat on cool sea and a vacuum is created which if the bung aint working 100% will allow a small amount of water in , i have this problem as i am on a drying mooring , am replacing bung with a high quality fitting ( brass i think ) as soon as i can be bothered to get the trailer out .

gotchiguy · 07 June 2012, 13:01

Quote:

Originally Posted by 9D280

Slap yer missis' vas oanit.

That's more like it

bicyclejuju1 · 07 June 2012, 13:30

Here are both sides of the back where the bungalow are. Both have new plugs. How can water leak from the top one (inside deck) to the lower one? Is there a hollow space between the 2. Boat is on a trailer and both plugs have a little coating of vaseline.

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bicyclejuju1 · 07 June 2012, 13:34

Should I replace the inserts that the plugs go into? I checked them and re installed them with some silicone to ensure a good seal. Is that the correct thing to do?

PeterM · 07 June 2012, 13:43

From several thousand miles away I'd be suspect of the D ring bolted to the transom brace in the 2nd pic. I'd suspect these could be leaking in to the void (yes there is a gap between the deck and outer hull) . Pull up the black plastic covers and have alook see and try tightneing the bolts on them ( assuming they are the 'normal' sort)

I'd suggest filling the hull to just over those but not as high as the tube/ hull join and see if the same happens with water in the void. If water is there it has to be these ( or if there are tie downs for a petrol tank on the deck? )

bicyclejuju1 · 07 June 2012, 13:58

I'm gonna go check the rings out now. I read a suggestion on a separate thread that suggested to attach the pump to the outer plug hole making a good seal w tape or plastic fitting. Then slowly inflate the inside. Then use the soapy water technique to look for bubbles. Anyone tried this?

PeterM · 07 June 2012, 14:10

Quote:

Originally Posted by bicyclejuju1

I'm gonna go check the rings out now. I read a suggestion on a separate thread that suggested to attach the pump to the outer plug hole making a good seal w tape or plastic fitting. Then slowly inflate the inside. Then use the soapy water technique to look for bubbles. Anyone tried this?

Never tried it but heard it will work. I underestimated the amount of water that can come through a loose fitting like those rings ( I assume one each side on your boat ) after an hour on the water in a recent boat the loose D ring in the bow meant I had an inch of water in the back of the boat .

Of course it shouldn't be a problem if it is this on yours as they wont have water over them when in use - unless you fill the boat with water !

Has it leaked into the void when you have put it on the water ?

bicyclejuju1 · 07 June 2012, 14:22

I haven't gotten in the water yet. I wasn't even planing on buying a boat. But this deal was too good to pass up. $100 for the boat, trailer and motor. I had to order the hypalon fabric, glue, and tube sealant from a river rafting place. (Much cheaper than a boat place). I thought it was all ready to go then I read about the bathtub test. Now I just have to fix this leak and I'm ready to conquer the gulf!!! Thanks for taking the time to respond and help a new ribber!

PeterM · 07 June 2012, 14:35

Wow $100 !! - that sort of set up would cost more like $1800 over here !

I'd not worry too much about the water in the hull void - its not really an issue as long as it doesn't fill quickly when on the water.

I think most RIBS if you stick a foot of water on the deck would end up with some finding its way in - after all thats why there is the ability to drain it.

boristhebold · 07 June 2012, 15:02

Some water always gets in, the bilge bungs let some in, rain water gets in also, I wouldnt worry about it if its not much. Have a look at how much water comes out of boats when they are lifted out the water and the bilge plug comes out next time you in a marina, it may shock you.

bicyclejuju1 · 07 June 2012, 15:44

Thanks for all the feedback! Y'all are great!!!

lskuang · 22 August 2022, 22:01

My boat leak from the center console joints, from top side deck sips into the body. usually when i am in idle when the pump is not on, comes from transom. pictrure shows when i blow air into the drain plug.

one day=1 gallon of water in the hull, hope it helps.

I register to this forum to reply this 10 years old thread lol.