Water in the Bilge

[Chris_Cardwell]

I recently (well a few months ago now) bought a Mirage 26. Lovely boat, very roomy for its size and in great condition. I was warned however that she was showing the early signs of Osmosis. Ive seen this before and its not the scary issue people make it out to be, however I have noticed there seems to be an excessive amount of water gathering in the bilges between visits.

The amount of water gathering couldnt possibly be the big O and I have checked the sea cocks, some have seen better days for sure but they all seem intact and serviceable. I am however new to having an inboard and suspect the water could be coming in through there, maybe the shaft as the water in the bilge seems oily/greasy. I am just wondering if anyone has had any similar issues or can give any suggestions as to where to look first?

Thanks in advance!
Chris

 

[concentrik]

Hello Chris, I can't think of a quick way to locate the source - you'll probably just have to look in all the likely places. Shut off all the though-hulls and see if it improves? It's worth bearing in mind that it could be rainwater from leaky windows/superstructure.

 

[PuffTheMagicDragon]

The first thing to check would be if it is salt water or fresh. A good candidate source for salty would be the shaft area. Try putting a shallow plastic container underneath the gland to get an idea of how much water is dripping in. Sources for fresh water are as Concentric has suggested, to which I would add condensation and, possibly, a leak from your fresh water system.

I am not familiar with the Mirage inside; are there any keel bolts / nuts visible?

 

[MoodySabre]

Stern gland is the obvious place to start. Does it drip when the boat is stationery? Do you give half a turn on the greaser before you leave the boat? If that is the source of the problem then dry out somewhere and repack the gland (lots of info on the net), top up the greaser and that should be it.

While you are at it check the condition of the hose that joins the stern galnd on to the dtern tube. If there are any signs of degradation then change it - probably need to get hauled out for that.

Otherwise you can dry the area round the thorugh hulls and keel bolts and spread some talc about to show the route of leaks to the bilge.

 

[awol]

Aye, the first thing to do is taste it, I'm afraid. If it is salt and you haven't been bouncing through waves or anchoring then check all through hull holes - rudder post, stern gland, cockpit drains (if there are any), sea cocks, log, depth sounder, anode bolts, there may be more. If not salt then you're on your own - there are just so many possibilities - but I recommend Cap't Tolley's Creeping Crack Cure for windows, screws, fittings, hatches, etc.
Good Luck!

 

[EdWingfield]

I had a slow leak that showed up midships. I assumed the leak was midships - wrong. It was entering via stern gland and seeping forward unseen.

But I support above skippers. Is it salty or fresh? Top tip. taste it only and spit it out.

 

[sailorman]

I recently (well a few months ago now) bought a Mirage 26. Lovely boat, very roomy for its size and in great condition. I was warned however that she was showing the early signs of Osmosis. Ive seen this before and its not the scary issue people make it out to be, however I have noticed there seems to be an excessive amount of water gathering in the bilges between visits.

The amount of water gathering couldnt possibly be the big O and I have checked the sea cocks, some have seen better days for sure but they all seem intact and serviceable. I am however new to having an inboard and suspect the water could be coming in through there, maybe the shaft as the water in the bilge seems oily/greasy. I am just wondering if anyone has had any similar issues or can give any suggestions as to where to look first?

Thanks in advance!
Chris

This time of year it more likely to be condensation

 

[Baddox]

As above, I’d start by determining if the water is fresh or salty. If salty, then check the stern gland and if not that, then try a dusting of talc around any areas under suspicion.

 

[TeamSpirit]

As discovered recently my water pump bearing gave in and without my alarm and main auto bilge pump my boat would have gone down, combination of the Yanmar inlet valve jammed a common problem prevented me turning off and was awaiting lift out to change to new gate valve from asap supplies.

Leak necessitated a late night visit armed with wooden bung and jubilee clamp sorted problem in minutes and then pumped out electric and manual pumps for an hour. I had noticed some water in bilge but not significant amounts so didn't explore and just used nappies to soak up and keep dry. After a run out for fuel top up the bearing finally gave in and was like a tap pouring in.

 

[Norman_E]

Certainly taste it, but even if it does taste salty it may be fresh water. The reason is that if the boat has had seawater in the bilges in the past and some has evaporated, there will have been salt deposited. If you are now getting rain water ingress, or even a leak from the freshwater tank you may well taste salt. I tasted salt in water in the bilge a couple of years ago, but the source of the water then was the fridge. Ice on the evaporator had melted when the fridge was turned off, and escaped because a drain in the fridge compartment was not connected properly.

 

[stav]

Wouldn't stress to much but work methodically through the issues. I had water in the bilge and think it was a combination of things but ended up being the stern gland needing repacking (but I changed it over for a dripless seal), leaking cockpit locker lid and the really big culprit was a split calorifier that only leaked under pressure. I found this out after replumbing the change over valves for the water tanks and spending ages checking the water tanks etc. I found the leak on the calorifier by taking it out and connecting it to a hose pipe and water issued out from under the lagging. thankfully managed to 'wipe on' a patch with plumbers solder. Dry bilges are so satisfying (says with a smile)!

Good luck with it but don't let it spoil some good sailing; it took me 3 years to complete the above jobs.

 

[Billjratt]

Everything above is valid, but my feelings are that the water may be pretty awful and tasting it might not be a good idea. It's all very well when everything is bright and shiny and you can see the bottom of the bilge clearly - the difference between salt and fresh is easily discernible. However if there's oil or anything else it's not so pleasant or in fact easy to decide, so another way of tracing the source is to puff talcum powder or similar all around the 'puddle' ie- up the wall of the bilge etc. any little streams will then become evident. If there aren't any, it may be dripping directly into the puddle in which case you will hear it, or the afore-mentioned tray will be full.
When ski-ing don't eat the yellow snow, when in Troon don't drink the harbour juice - rats piss, weils disease, other things. .

 

[William_H]

I wonder if OP could try measuring conductivity of the bilge water by putting the probes of a multimeter on high ohms into the water. Note the reading and spacing of the probes. Compare to sea water. If similar readings with same probe spacing then it is sea water. A higher resistance would indicate fresh water even if with some salt. I have never tried it. Is this a dumb idea? Must be better than tasting.
My guess is most likely rain water getting around fixtures and windows. But check everything. My little boat gets a lot of water in bilges but only when I have it home on the trailer for the winter. (never rains in summer so no problem) good luck olewill

 

[alteredoutlook]

Exmaine all your hoses for leaks/cracks. It took me 2 years to discover the source of my damp bilges. Mine was due to a crack in an obscure part of the emergency bilge hose pipe - the pipe would fill when heavily heeled on port but would only leak when on starboard - very frustrating to find.

 

[Jabs]

I spent months, on and off, looking to find where water in the bilge was coming from.

It was somewhat salty, due to there being salt in the bilges!

Turned out to be a leak from the top of the potable water tank and it only leaked under very specific conditions.

Drove me mad and I found the source purely by chance.

Root cause: Faulty water contents sensor.

Why? It took three plus hours to indicate full so I was leaving the water filling for hours and hours leading to pressurisation in the tank which caused a leak!

I think these things are more substance than problems!

Tony.

 

[Neil]

First time I'd tasted a puddle in the stern locker, it turned out to be battery acid. Urgh! I have damp bilges some times but not others - often it's perfectly dry. Once after waves were crashing over the boat, it was all over the boat, in every locker. I still have a leak under benign conditions and I've tried the talc trick without success so far. When I get a bit of time I'll conduct an extensive and logical elimination process. Unfortunately, I'd prefer to sail the boat instead.

 

[ghostlymoron]

I used to have a mirage 28 which is like a 26 but bigger cockpit. I first noticed water ingress during the delivery trip and tried renewing pipework etc but eventually found it was leakage from around the starboard keel joint. Had it professionally fixed at great expense but no further problems. I tasted the bilgewater several times and there is always a hint of salt but seawater is strongly salty and unmistakable.

 

[Cardo]

Our boat takes on rain water, through various small leaks on the deck. A quick and easy way to tell would be to see if the water level rises without it raining!

 

[Burnham Bob]

I've given up trying to find my leaks. On a couple of occasions over the last five years I've had lots of water in the bilges. Pump it out and the boat stays dry for a couple of years (a bit of water only which I put down to condensation) Then it happens again for no apparent reason. If it was every time we sailed in heavy weather, used the engine for long periods or heeled a lot I'd understand it but its not. Once every two years or so it seems to happen. Same with the rainwater leak above my bunk. Torrential and sustained downpour three years ago and my cushions got wet. Filled some old screw holes and no problem during subsequent downpours. A while back, again torrents of sustained rain and a small leak in the same place- but enough to necessitate drying the cushions. No obvious sign of a leak anywhere. Dried cushions but nothing else attended to, and during the stair rods we had for hours and hours a while back, the boat stayed dry as a bone. So I'm giving up looking and coping with the gremlin adminstered leaks as they arise. Unless any forumites can explain?

 

[Chris_Cardwell]

Thanks for all the replies guys, some great points and ideas being raised here.

I was down yesterday and closed off all the sea cocks and gave the stern gland a half turn of grease and it seems to have drastically cut down the amount of water getting in. When I left yesterday I made sure she was bone dry, today there was maybe 2 small sponges worth of water in the bilge which I suspect was still in the boat but took time to work its way there even after I closed off the sea cocks.

My suspicion is it could be coming in through a pretty badly corroded seacock for the engine discharge, it is definitely sea water as I tasted it and there has actually been very little rain lately. I also had a look at the stern gland itself and it all seems to be in good condition, although there was definitely some water underneath it, so it could also be a possible cause.

I also discovered small traces of water under the seats where the keel bolts come into the hull, this is slight but im surprised as the keels were rebedded only a few years ago (according to the sales documents) but this water cannot work into the bilge as both under seat storage compartments are sealed. It is a bit concerning however that the keel bolts are wet.