Cabin full of water

[prudencepayes]

We have an Arran 550 which is an 18ft cruiser/sailor, moored on the Norfolk broads. It is about 30 years old. Last summer we noticed that the cabin was filling with water below floorboard level, and each time we used the boat we had to pump out several buckets of water. We wondered if it was a leaky cockpit floor letting in rainwater, but on a couple of occasions the boat was starting to refill after a short sail in dry weather. Also the water looked like broad water, not rainwater. We also wondered whether having sailed the boat could have changed the angle of the boat and moved more water to the bottom of the hull. We had the boat craned out so that we could check the hull. The hull looks sound, and the boat is still full of water, which is not draining out at all. Does anyone have any ideas where it might have come from?

 

[Norman_E]

The first suspects are usually the through hull fittings like a depth sounder or heads inlet, not forgetting the shaft tube if you have an inboard engine. If your boat has a fibreglass hull, these are usually watertight. Give us more details. If there is no obvious source of leakage through the hull, then rainwater ingress is more likely.

 

[oldharry]

Tracing mimnor leaks isa pain! The usual way of testing for rainwater is to put the boat in seawater, then see if the bilge tastes salty. No good on the Broads though.

So, what you have to do is to dry the bilges out completely, using a sponge to get he last drops out, then watch closely to see whether more water appears. if so, where is it coming from? Is it running down from somewhere? If so follow the trickle back - by simply sponging dry, then again and again till you find the point of ingress. Patience is required as water can run a surprisingly long way!

IIRC the Arran is GRP? That makes it much easier, as the water will only come in where the hull is piereced; skin fittings, keel bolts, anywhere anything goes through the moulding is suspect.

Sponging and waiting. If the water appears 'from nowhere' round a fitting - theres the leak.

The water will not run out again unless the boat is filled inside to above the water line - even then some leaks work better one way than the other!

And yes, you can get a leak above the water line which only lets water in while the boat is tipped up.

Have fun!

 

[BrendanS]

Another old trick is to get everything as dry as possible, then puff talcum powder around. Then you can see the trickle pattern of where the water is coming from in the talc. Depends on how easy access below the floor is

 

[castaway]

Or another way is to get a stick of chalk (poss on a a stick) and draw lines along the inside of the hull

Regds Nick

 

[simonfraser]

rudder fixings ?

 

[prudencepayes]

Thanks for these ideas. It so strange that the water is not draining out, even though the boat is out of the water standing on its bilge keels. We wondered if it was a problem where the metal keels were attached to the hull, but then you would expect the water to drain out the same way when the boat came out of the water.

 

[MoodySabre]

If the water is not draining out then
1. the leak could be between the top of the water in the bilge and the waterline. Normally the bilge is the lowest part.
2. If it is leaking through the keel bolts then the keels will be pushed up against the hull when on the hard but hanging whilst afloat.
3. The weight of the boat in the water will force water through a small hole/gap but there is not much pressure to push it out again.

Anyway don't leave the boat with water in it or you will get lots of mildew and smells.

Stern gland is favourite followed by keel bolts. Good luck.

 

[Caer Urfa]

Had a sort of similar problem two years ago and spent months looking for the cause, same simptons sea water not fresh water.
Final found out water was being shipped aboard via the toilet when the boat healed to much under sail!
Hope it helps
Cure, easy shut all valves to toilet under sail, problem solved!

 

[bumblefish]

If you have the time and the patience then you can close off any 'known' leaking areas, such as the companionway, with duck tape and then pump air in via a fitting. Use the old soapy water around suspect areas and the leak should reveal itself like a hole in a bike tyre! I read that somewhere but can not remember where, age!

 

[mikemonty]

Wouldn't recommend it!
A few fractions of a PSI acting over several thousand square inches amounts to BIG forces.
At least if you do try it, have a camera running - I'd like to see the bit where the deck pops off - on YouTube!

 

[Billjratt]

Do you have freshwater tanks (leaking)? also look at the pipework for the engine cooling and exhaust. Is it shaft drive or outdriveleg, the bellows and/or stuffing box may need looked at. If it can't leak back out again maybe it's syphoning in, is there a heads fitted...

 

[oldsaltoz]

G'day prudencepayes and welcome to YBW forums,

<<<you would expect the water to drain out the same way when the boat came out of the water. >>>

You will have more pressure on the leak when the boat is in the water and very little when she is out, also note the hull shape may change when resting on the keels and perhaps close the leak assuming its below the water line and not rainwater.

Avagoodweekend......