Finding a leak

oGaryo

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Hi.. took the boat out at the weekend and on ruturning there was a notable amount of water in the bilge... Can anyone give me a method to locate where it's coming from..

some pointers:

Cabin floor tends to get wet near to the heads door.. I put this down to condensation.. it's not drenched, just damp, I've put a carpet over the fitted carpet to keep the original clean, could that trap moisture between the two?.

Looking in the shower pump area at the front of the rear cabin, there's a small amouint of water in there too, about a cm deep, not alot.

I have a small drip from the blue plug at the front/base of the engine at idle, can this become more than a drip when underway.. the single point drain system on the Mercruiser 5.0l MPI doesn't shut off tightly, it continues to rotate after reaching its closed setting so presume has been overtighten at some point..

I'm not sure if it's salt or fresh water in the bilge.. it's clear water though not dirty...

I'd estimate about a gallon in total.

Could this be build up of moisture that sits in the length of the boat unnoticed until I open the transom drain plug on the slipway incline? I suspect there's too much for that and I have a leak somewhere.

Boat has a seawater toilet + holding tank and fresh water tank + calorifier

Thanks

my approach is going to be to fit the bung before getting to the slipway, and then remove it once of the incline and see how much water comes out to give an indication of condensation.. I'll mark the level of water in the tank and see if that drops when using the sinks and finally, will catch the water in a bucket and get someone other than me to taste if for saltiness:D

any other ideas please?
 

oGaryo

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thanks for that.. pennies just dropped after reading the first post! there's always water in and around the helm floor where rain water runs down the canopy struts and instead of draining off the sides, it finds its way in to the boat.. I suspect it sits there in the vee of the hull until I get the boat on to the slipway... will test the theory next time out by putting the bung in with the boat when level, taking her to the slip and then removing it to see what comes out.... then go for a run and come back to see if she's taken on water
 

dragoon

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I know it sounds horrible, but tasting the water will tell you if it's sea or fresh water.

Another useful tip is to use talcum powder, and make little dams/boundaries to see where the water is coming in from.

Good luck finding the leak, I know just how time consuming it can be. It's definitely a worthwhile cause though.

Cheers,
Paul
 

zt260

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That blue plastic plug is a drain plug and shouldnt be dripping there should be a small oring under the flange on the plug so when it tightens up it seals,if the thread has been stripped i would replace it,if it drips when the engine is at idle i would have thought it may get worse under higher revs and a hot engine
regds ash
 

oGaryo

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thanks guys, I'll replace the plug as it's pennies but I think it's more to do with the single drain system being slightly buggered.. it bypasses the lower drain plug and I don't think its closing fully.

will give the talc a go too.

p.s. regarding my intial post, last para... on rereading "I'll use the sinks and monitor if the water level drops in the water tank"... doh, what was I thinking?:D:confused:
 

rafiki_

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Gary, I would be tempted to take the carpet up when you are not on board. If this continually gets wet, it will stain and smell, and be very difficult to get rid.
 

oGaryo

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will do.. the thing is, the top carpet is a hessian job and when not fitted, the lower carpet remains dry so I'm putting it down to condensation created between the two... I may be wrong as I must admit I've not looked in to it in any great detail whilst sorting other things out... will take up the hessian carpet and rethink how I keep the original carpet clean... thanks for the advice
 

oGaryo

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took the boat out at the weekend from Calshot to Cowes and back again... to return with more water (salt) pouring out the back end drain when on the incline at the slipway... I'm homing in on where to look with the following observations:

- pretty much bone dry in the bilge before getting the boat up the ramp so suggests the leak is amidships and forward.

- when taking her out recently in a flat calm for a longer period, circa 20 mile run, there was very little water coming out on the slipway which suggests the ingress is above the waterline.

so, going to check the anchor/windlass locker, portlights, and all through hull fittings.

a friend has suggested getting some food dye and pouring water in and around those places that are suspected of leaking starting with the anchor locker as the prime suspect considering the amount of water ingress (a good few litres this time).. the anchor locker is the only place with a downward facing drain so would be capable of letting in that volume of water over a short period of time.
 

oGaryo

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did some investigating yesterday and think/hope I've sussed this.. firstly, I think I was wrong to say the leak is up front, it could be from anywhere and just settles about the boat when level as there's a drain hole between the bilge area and midship section of the boat.

I did find a leak through the port side nav light that's now fixed... I believe this is a simple case of water coming in over the swim platform in a following sea which I'll have little chance to do much about considering the chop in the solent and in particular, my perserverence in adhering to Colregs meaning I'm changing course and speed fairly frequently not so much to keep in pace with the waves but to avoid other boats... coming off and on the plane with waves coming over the swim platform and hitting the transom will no doubt result in water coming in to the boat...

I'll spread a bit of talc on the top of the ledge above the bilge and see if it gets washed away next time to proove the theory
 
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spannerman

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Have you checked the 8 per side hose clips on the rubber joints in the exhaust system between riser and bend and bend and downpipe, these open dribble when under way if not tightened sufficiently.
 

oGaryo

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Have you checked the 8 per side hose clips on the rubber joints in the exhaust system between riser and bend and bend and downpipe, these open dribble when under way if not tightened sufficiently.

yep, checked them all yesterday, no signs of rust marks on the outside of the risers either (will be checking the water jacket at the end of the season). thanks for the advice:cool: There are salt deposits toward the rear of the engine starting above the steering linkage so that's why I've presumed it's coming in from outside the engine cover and passing over the rear of the engine bay... pretty **** design if you ask me... can be compensated for with good seamanship in following seas but hard to ride the waves in a choppy solent and I think most of the time it's occuring when getting on to the plane, expecially last week when I was trying out a new prop, took ages to get out the hole
 
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Deleted User YDKXO

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I know you're checking all skin fittings but also check the handrail stanchion bases on the sidedeck and around the fuel and water fillers to see whether they are loose or the sealant is obviously broken. FWIW, we had a mysterious leak on our last boat which manifested itself as dampness on the floor of one of the side cabins and water in the bilges. I eventually traced it to one corner of the windscreen where the sealant had failed, presumably due to flexing of the screen when the boat bashed over waves. The water entered the boat there, migrated on top of the overhead panels down below until it found a gap. Anyway resealing the window cured it
 
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