Water seeping in through keel bolt

[Haddock]

Hello everybody,
So far on my 2005 Bav 38Cr, which I bought second hand in 2010, the aft bilge compartment where the bilge pump is fixed, appeared always dust dry, and I must admit I therefore checked it only occasionally.
Lately however I found some brownish bilge paint powder all over the compartment and therefore filled the compartment with tap water to clean it up and check the bilge pump at the same time.
The pump worked fine although it was unable to empty the compartment completely, so a small amount of water covered the bottom. I dried it up with a sponge and closed the compartment.
When I returned two days later there was about an inch of seawater standing in the bilge and the paint was wrinkled all over the place. I tried to dry it out again but apparently a very small amount of seawater was seeping through around one of the bolts. Strangely enough it gradually slowed down and then seemed to stop.
I dried it out once again but then had to leave, so I'm not sure if stopped completely or only temporarily.
Anyone has any idea what's going on here?
Thank you for your attention.   

[allyfiji]

If its definitely not seeping in from other bilge compartments then try hammering all the keel bolts to see if you can detect any separation? I believe a less than sturdily embedded keel bolt will make a different (tinnier)  sound to the others.

[Ziffius]

I had a similar experience with my Bav 39, completely dry bilge on way from UK to the med the last few weeks on The boat suddenly noticed a fair amount of clean water in bilge but not enough for the pump to grab it. Sponged it dry and it only slowly came back. I haven't identified source but think it is fresh water. When I go back in the spring I will try and locate source but it appears to come from between the the ribs and so could be coming anywhere. One thing was I didn't use the showers on way from UK! My first thought had been KEEL BOLTS but hopefully it isn't them

[Odysseus]

It's probably the fresh water pump, usally a sureflo pump, the diagram does not like being frozen so if you did not disconnect the pipes in the winter it will distort and leak. Check around the pump after putting a plastic bag, (  without holes) under and around the pump, you will soon see if it's the pump.

Hope this helps
Odysseus

[Haddock]

It's probably the fresh water pump, usally a sureflo pump, the diagram does not like being frozen so if you did not disconnect the pipes in the winter it will distort and leak. Check around the pump after putting a plastic bag, (  without holes) under and around the pump, you will soon see if it's the pump.

Hope this helps
Odysseus

Thanks for the input but here in south of Spain there is no freezing winter, the fresh water pump has no leaks and the engine compartment is always dust dry and shining.
The water in the aft bilge compartment clearly seeped in around one of the keel bolts, but then strange enough stopped.

[Haddock]

I had a similar experience with my Bav 39, completely dry bilge on way from UK to the med the last few weeks on The boat suddenly noticed a fair amount of clean water in bilge but not enough for the pump to grab it. Sponged it dry and it only slowly came back. I haven't identified source but think it is fresh water. When I go back in the spring I will try and locate source but it appears to come from between the the ribs and so could be coming anywhere. One thing was I didn't use the showers on way from UK! My first thought had been KEEL BOLTS but hopefully it isn't them

Thanks for the input but in this case it was seawater seeping in around one of the aft bilge compartment's keel bolt and no fresh water. Strangely enough at some undefined moment it stops seeping in...

[Haddock]

If its definitely not seeping in from other bilge compartments then try hammering all the keel bolts to see if you can detect any separation? I believe a less than sturdily embedded keel bolt will make a different (tinnier)  sound to the others.

Thanks for the input but all bolts are sturdily fastened and don't show any loosening

[Ricd]

On our 2000 B34 some years ago we had a symptom very similar to yours.  The water in the bilge was salty and appeared to well around a keel bold as if that was the source.  However further investigation showed it to be water from the decks seeping in via toe rail bolts being duct-ed towards a rib and then down into the bilge compartment where the keel bolt was.  The water seeped in slowly and intermittently as the boat moved in its berth allowing more water to seep from the rib into the bilge, sometimes being visible and then appearing to stop but always present on returning to the boat after period.  As I said it was salty water which I first thought was sea water.  We identified the root cause by SWMBO playing a hose systematically along the toe rail while I watched for signs in the bilge.  Our solution was to retract the toe rail bolts a cm, apply a blob of silicone to the threads and re-seat them.

Hope your problem is equally simple and resolvable

[IslandAlchemy]

My guess would be either toerail bolts or hull/deck joint seal. As said above give it a good soaking with a hose and see what happens.

[Haddock]

On our 2000 B34 some years ago we had a symptom very similar to yours.  The water in the bilge was salty and appeared to well around a keel bold as if that was the source.  However further investigation showed it to be water from the decks seeping in via toe rail bolts being duct-ed towards a rib and then down into the bilge compartment where the keel bolt was.  The water seeped in slowly and intermittently as the boat moved in its berth allowing more water to seep from the rib into the bilge, sometimes being visible and then appearing to stop but always present on returning to the boat after period.  As I said it was salty water which I first thought was sea water.  We identified the root cause by SWMBO playing a hose systematically along the toe rail while I watched for signs in the bilge.  Our solution was to retract the toe rail bolts a cm, apply a blob of silicone to the threads and re-seat them.

Hope your problem is equally simple and resolvable

Thanks for your input and I will check it a.s.a.p.
Hope you're right!

[Haddock]

On our 2000 B34 some years ago we had a symptom very similar to yours.  The water in the bilge was salty and appeared to well around a keel bold as if that was the source.  However further investigation showed it to be water from the decks seeping in via toe rail bolts being duct-ed towards a rib and then down into the bilge compartment where the keel bolt was.  The water seeped in slowly and intermittently as the boat moved in its berth allowing more water to seep from the rib into the bilge, sometimes being visible and then appearing to stop but always present on returning to the boat after period.  As I said it was salty water which I first thought was sea water.  We identified the root cause by SWMBO playing a hose systematically along the toe rail while I watched for signs in the bilge.  Our solution was to retract the toe rail bolts a cm, apply a blob of silicone to the threads and re-seat them.

Hope your problem is equally simple and resolvable

Thanks for your input and I will check it a.s.a.p.
Hope you're right!

After a lot of hosing to clean the boat nothing appeared in the bilge.
After a few days of sailing and sponging a very small reappearing quantity of water, the bilge finally became and stayed completely dry again like before.
Still don't know what really happened but hope it'll remain like that.
Thanks for your input.http://www.bavariayacht.info/forum/Smileys/bavaria/thumbsup.gif

[Ziffius]

Just a thought, maybe the bucket of water you put in would have spread into the rib areas between the bilge compartments. That water might the have trickled back into the areas round a keel boat making it appear to come from a bolt. As to the salinity??? Maybe the dirt and grime from the rib area

[Sanna]

It's unlikely to be the keel bolts but water passes through these bilge areas when leaking through the hull/deck joint bolts. A vast number of GRP boats, not just Bavarias, leak water through these joints. We live onboard a Bavaria 50 Ocean which we are circumnavigating and we had problems with water ingress in big seas and rainstorms and could not identify where the water, both fresh and salty was coming from. On reaching Thailand we took advantage of their cheap costs to replace our teak decking and the toe cappings were removed. The problem was evident straight away. All of the stanchion through fittings and deck to hull joint bolts had worn both their seals and in some cases with the stanchion bolts, the GRP hole had become enlarged. These were all resealed and the problem disappeared for about three years. They've just started to leak again which I suspect is the stanchion through bolts wearing around the GRP. The toe cappings can be quite easily removed with care and reused.

I was recently talking to a shipwright and he comes across this problem regularly on most GRP boats. He advised removing the stanchion and joint bolts and countersinking the hole. This then forms a washer type seal with sealant when everything is replaced but even then will only last a number of years. The seals breakdown as the hull and deck flex under more extreme use, especially the stanchions which are designed to move and give in any event.

Hope this helps. Our blog site is sailblogs.com/member/eastwards for more info. 

[Craggles]

Have the same problem with my 2008 bav 37 cruiser. As mentioned in my first post, the hull deck seal on the bow is shot as it has only had sika flex to glue and seal. When sailing into a bit of slop, the salt water splashes under the crappy seal and the water gradually makes it's way to the bilge and as mentioned previously, when the boat moves around water keeps coming through until it dries out. My question is why don't Bavaria put a slightly deeper area in the bilge for collection? I also leave a sponge in the bilge to clean out better.
I am going to reinforce the bow to stop the deflection that breaks the seal which makes the deck forward of the anchor locker flex that bad I am worried that it will snap off! We use a snubber ALL the time and retrieving the anchor is a concern even in a 1 mtr sea.

[Stockie]

Thanks for the info, my 2006 Bav37 has water coming from the transverse rib in the bilge.  So does this rib collect water from higher up in the hull?
I’m guessing a day or so re-doing the stanchion bolts could be a start!
Cheers Richard

[dawntreader]

Thanks for the info, my 2006 Bav37 has water coming from the transverse rib in the bilge.  So does this rib collect water from higher up in the hull?
I’m guessing a day or so re-doing the stanchion bolts could be a start!
Cheers Richard

[Bav37 2006 too] This is most likely to have come from elsewhere and collected inside the rib(s)  Check side walls for signs of leakage especially after heavy going. Posts above show classic problem areas. The ribs are slightly deeper than the bilge area and water pools in them. To test this, dry around the hole in the rib and put your finger inside  I inserted a micro-fibre cloth rolled lengthwise into the hole to draw the water out. Otherwise, every time you pitch, water 'seeps' out.

[Salty]

I agree with Dawntreader, but also check your Volvo exhaust silencer if it hasn’t already been changed, the stainless end caps, particularly the one at the low end of the silencer are favourites to corrode through and leak while your engine is running. On my B36(2002) this used to show up as water in the engine compartment, but the arrangement on your boat might be different. This would of course result in salt water within the bilge area, and where the water would travel through the box section floors until it reached the area where your bilge pump is located, and would exit the floors through the round holes that the Bavaria factory provided. However, because those holes are slightly above the bottom edges of those box sections, some water would be retained within them to leak out just when you thought you had finally got a nice dry bilge again.

[tckearney]

I had a sililar problem. It was not the keel bolts to prove it I cut a few lenghts of plastic guller pipe about 25mm long.  Then put a small amount of silicone sealer on the edge of the pipe bits and placed them around the keel bolts.  As they did not fill with water it proved the bolts had not been leaking.  Ive left them there just to give me confidence