Cut holes to access bilge
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Forum Name: 400
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Topic: Cut holes to access bilge
Posted By: toholthe
Subject: Cut holes to access bilge
Date Posted: 08 March 2018 at 21:48
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I would like to cut holes to the inner liner in my Hanse 400 2007 in order to manually sponge out last drops of water in the bilge. Thinking two or three holes big enough for putting hand trough. Would this be a bad idea strength wise? Should not think round holes in this area would effect strengt, or? Pic is from Hanse 370, but looks similar in our 400. Marked areas for potential holes 
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Replies:
Posted By: Gaga
Date Posted: 08 March 2018 at 22:51
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I am using a vacuum cleaner to suck the remaining water Fitting a small soft plastic pipe of about 1 cm diameter and access through the Holes which are between the floor boxes. It works and needs no additional holes. Just an idea which may be worth trying. |
Posted By: StavrosNZ
Date Posted: 08 March 2018 at 23:07
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i would not cut holes of any significant size and number in the structural grid, this is arguably the most import part and most highly loaded part of your boat. Any holes will weaken the structure. ------------- Stephen 2010 H400 #691, Auckland, New Zealand |
Posted By: SausalitoDave
Date Posted: 09 March 2018 at 01:33
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I had this problem when I first got my 505. I used a shop vac as Gaga described, and that works. However, About 3 years ago I bought a dehumidifier that runs whenever the boat is not in use. It has a humidistat, so it does not dry out the wood too much; however, it has completely eliminated mold anywhere (including below the sinks). I keep the doors to the cabins and under the sinks open. The boat is always perfect all the way down to the bilge. Dave Festina Lente Sausalito, CA US
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Posted By: Carlosailfan
Date Posted: 09 March 2018 at 07:49
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Just an other approach, where is the water coming from ? In my opinion it would better to stop the ingress than drilling holes to let it pass. I would never drill holes into the structural frame, this is the hart of the ship. My 385 is really dry after my latest intervention to take away the water leakage of the overflow valve from the warm water heather. Maybe i am a bit nerdy on that but water must be outside the boat and not inside.  ------------- Best regards /C |
Posted By: Peter-Blake
Date Posted: 09 March 2018 at 08:40
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Do not drill a hole there: 1. it is the major structural area, as stated already 2. You will not find the lowest part of your boat if you drill a hole there!! Why? In this area Hanse adds a thick bed of glue before inserting the inner structural construction of the hull. You will find a mountain of glue! 3. Use a endoscope camera for inspection though the existing holes in the next structural compartment beside the keel (See your foto). It works 4. Use a hose on a wet vacuum through the existing holes 5. Make sure you find the reason for the water ingress. ------------- Blake 370 
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Posted By: 415 Singapore
Date Posted: 09 March 2018 at 08:44
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I totally agree with Carlos, after solving a couple of minor issues mainly with Air con condensate pumps and poorly fitted jubilee clips our 415 has been remarkably dry even during the heavy monsoon rains we can get here. All the best Paul ------------- Paul - Night Train - 415 #136 |
Posted By: Ratbasher
Date Posted: 09 March 2018 at 10:04
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Agree with general consensus; don’t do it. After an issue with leaking hull valves I described on another thread, I found that water channels through the bilges in a way you might not expect. The lowest part of the bilge is actually under the galley sink in a 400 and not by the bilge pump; indeed it seems like if it gets to the pump you’ve serious ingress already. To get rid of residual water in the void spaces I use the oil vacuum pump which has a long, flexible nozzle that can be used to search out water. Every so often I lift the boards to give everything a good clean and allow evaporation, ------------- H400 (2008) 'Wight Leopard' Gosport, UK |
Posted By: toholthe
Date Posted: 09 March 2018 at 13:23
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Thank you for all the answers. I do not have any leak and my boat is completely dry (for now). After 10 years with different boats my experience is that there will eventually come water to the lowest level of the boat. It can be rain from a hatch we forgot to close, kids spilling drinks, leak from freshwater system, wet cloths dripping etc. etc. In my previous boats which was older boats without an inner liner I
have kept the bottom of the boat completely dry. Understand with the Hanse
I just have to live with the fact there will always be some moisture in the
spaces not able to dry out by towel. I will buy a dedicated oil extractor for
this purpose. Seems like a smart idea. I will also buy a 9V water alarm and put
under the sink so I know if any water is entering the boat. |
Posted By: Ratbasher
Date Posted: 09 March 2018 at 16:24
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Good luck. Your suggestion of a water alarm below the sink is a good one. I just check the area as part of daily checks and always look there first if I’m at all concerned but agree that an early warning device would be smart as long as it’s not triggered by small amounts of the inevitable condensate. ------------- H400 (2008) 'Wight Leopard' Gosport, UK |
Posted By: Captain Dan
Date Posted: 21 June 2018 at 15:45
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Wet Vac, you can place a 3/4" pipe in to the hole behind the last keel bolt section, just had to do this today to my H400, issues with the stringer matrix coming unstuck means that water has come from anywhere and collected aft of the keel area. A 3/4 pipe pushed in about 6" then attached to a wet vac removed around 50L of water, this was not seen in any great volume anywhere else in the boat, clearly not a great design by Hanse.
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Posted By: Silver lining
Date Posted: 24 July 2018 at 16:37
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Guys - just on this topic . Hanse 400e - 2007 I have just noticed 2 weeks ago under the sink, where sea cock is , about 1 inch of water, when I bend down and look forward with a torch it seems to be in the next box section i.e under the saloon table ? I sponged most of it out, all being I cannot reach under the saloon table floor boards. This was not here last year ? Two things which spring to mind : 1. We took a massive wave over the entire boat in may, and nearly washed a crew member over board ! ? 2. I removed the Deck covers over the halyards to power hose all the dirt, they have not been off since factory ? Most of the water has been moped up (apart from the forward section - which will be a winter project !) and it has stayed that way . Thanks ------------- 'Silver Lining' 400e #199 |
Posted By: silversailor
Date Posted: 25 July 2018 at 19:52
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When my 370 was a few years old I found water in areas that did not drain to the bilge and which were inaccessible. Eventually the water would seep under the floorboards in the aft cabin and there was water sloshing around an inch or so deep in the aft cabin. After trying everything, Hanse finally suggested checking the seal between the outer and inner hulls where a circle was cut out to mount the saildrive. We found that the seal between those hulls had broken and that was the source of the water intrusion. My local yard repaired it and it has never been a problem since. ------------- Silversailor South Haven, MI USA S/V Legacy 2010 Andrews 28 |
Posted By: Silver lining
Date Posted: 25 July 2018 at 23:28
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Thanks @ silver sailor - I will check the aft cabins , although the water seems to be located starboard side forward. I think I can remove the storage box under the seat base , just in front Of the galley - the water seems dirty , almost brown in Color - with no smell ? As if it’s been there for some time ? I am completely puzzled ... but since mopping it up , it’s almost disappeared . I would love to know the source of entry though  It’s sea water , and not fresh water . ------------- 'Silver Lining' 400e #199 |
Posted By: silversailor
Date Posted: 26 July 2018 at 01:32
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When the area between the hulls was cleaned out there was lots of debris including fine wood filings that made the water brown. It's possible that your seal is not broken completely and that you only take on water when you are heeled a particular way and at a spped sufficient to but strain in the seal. Worth checking out if the problem continues. ------------- Silversailor South Haven, MI USA S/V Legacy 2010 Andrews 28 |
Posted By: Silver lining
Date Posted: 26 July 2018 at 07:48
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Will do , thankyou ------------- 'Silver Lining' 400e #199 |
Posted By: samuel
Date Posted: 26 July 2018 at 12:48
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I have written a number of articles for the Practical boat Owner magazine recently & in the summer issue Number 628 i wrote about a wandering hose solution to remove small quantities of water from areas of bilges such as those that you show. I also use mine for water that collects under the engine etc and similar spillages I cannot publish the text as I am under contract to PBO; but basically you insert a hoselock fitting in the shower hose pipe just before the pump. I actually fitted a bit of extra pipe in before the pump to make it easier to get the hoselock in. I then obtained a 10 ft length (need longer for bigger boat) of hose of the same diameter & fitted a hoselock connector so that I could swop the shower hose to the new hose easily. On the other end of the hose I put a 300mm length of copper gas pipe (longer for deeper bilge)& a gas pipe fitting & put this into the end of the pipe & held it with a jubilee clip. I drilled an 8mm hole in the floor on a veneer line so it does not show. Poke the copper pipe in vertically until it reaches the floor. Turn on the shower pump & suck out the water. Being only 8mm diameter it sucks up water to a depth of 1mm It can be moved about the boat including under the engine & if there is a lot under the engine then take the copper pipe off & use the full diameter. if the hose does not want to prime immediately then stick it in a sink of water to prime it first It is handy for any spills about the boat. I have even drained the heads when i have had problems provided there has been nothing solid in the water When done just re connect the shower hose ------------- Daydream Believer- Hanse 311- No GBR9917T- Bradwell Essex |