CONTESSA 32 ASSOCIATION Homepage
Forum Home Forum Home > Technical Help > Internal Fixtures and Fittings
  New Posts New Posts RSS Feed: Keel water tank, off-taste...?
  FAQ FAQ  Forum Search   Calendar   Register Register  Login Login

Keel water tank, off-taste...?

 Post Reply Post Reply
Author
Message
Tazling View Drop Down
CO32 Members
CO32 Members
Avatar

Joined: 16 Jan 2013
Location: Cortes Isl BC
Online Status: Offline
Posts: 23
Post Options Post Options   Quote Tazling Quote  Post ReplyReply Direct Link To This Post Topic: Keel water tank, off-taste...?
    Posted: 15 Jul 2013 at 2:08am
Love my CO32 but her integral water tank (in-keel, below the cabin sole) seems to impart a funny taste to the water -- not really potable, even with a filter inline.  It is crystal clear, just tastes strange.

Inspecting I see a couple of things:  there's stuff growing on the tank walls;  the gelcoat is cracked in many places;  and the inspection port lid (a 6.5 inch diam threaded plastic dealie in about an 8 inch dia plastic flange) is not watertight -- when I overfill the tank, water comes seeping out around the allegedly secured port.  I also see that there's a baffle between the fore and aft portions of the tank, making it (ahem) "challenging" to clean more than a tiny portion of it.

Other than dumping some bleach in and living with chlorine taste in addition to strange off taste :-)  does anyone have suggestions for cleaning out a tired old integral water tank?

cheers

de
..... Bound is boatless (wo)man .....
Back to Top
admin View Drop Down
Admin Group
Admin Group


Joined: 02 May 2009
Online Status: Offline
Posts: 46
Post Options Post Options   Quote admin Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2013 at 10:57am

If the tank is GRP there is a reasonable chance if has osmotic blistering and this will make the water taste “off” even after a short period of storage, no amount of cleaning will fix this, trust me I tried and tried again.   The only option was to replace the tank with a new one in stainless steel.  Clean and fresh water ever since now, even if stored for some time.  I think some people have lined their existing tank but I’m not sure of the cost of ease of doing this.

 

Sorry this is probably not the answer you are after.

Back to Top
James Chew View Drop Down
CO32 Members
CO32 Members


Joined: 13 Apr 2012
Location: Falmouth
Online Status: Offline
Posts: 29
Post Options Post Options   Quote James Chew Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2013 at 6:15pm
Is there anything to be said for steam cleaning it to kill the living stuff?
Back to Top
Tazling View Drop Down
CO32 Members
CO32 Members
Avatar

Joined: 16 Jan 2013
Location: Cortes Isl BC
Online Status: Offline
Posts: 23
Post Options Post Options   Quote Tazling Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2013 at 6:53am
Hmmm, "replace"?  as far as I can tell the tank is a void in the keel;  I'm not sure how it could be replaced -- my impression is that outside the tank walls it's all ballast.  Could be wrong about that though!  at any rate it spans quite a section of the cabin sole, major boat surgery to get at it...  I was thinking maybe a pressure wash.  In the meantime I'm carrying drinking water in bottles, and using the tank water for washing-up (of dishes and persons).  This will get me through local summer cruising all right.

I'm trying to come up with a description of the off taste and all I can say is it is as if there were a bit of bicarb of soda mixed in.  Not very palatable!  Is that typical of osmosis?




..... Bound is boatless (wo)man .....
Back to Top
George Isted View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 08 May 2009
Location: Solent
Online Status: Offline
Posts: 368
Post Options Post Options   Quote George Isted Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2013 at 9:36am

Unfortunately, changing the tank is a significant undertaking, the floor has to some up and then the tank removed where it is bonded into the gap between the hull sides just above the lead ballast.  I’ll email you a couple of pics but also see the technical section of the website that has a paper on replacing the tank and floor.

 

Just a thought but have you tried a shock-treatment of the tank and it’s pipework with chlorine bleach, you can later neutralise of most of the chlorine taste with a vinegar solution.   As well as a clean tank have you checking/replacing the pipes as they can also contain lots of nasties.

 

Does the inside of the tank have any blisters or pimples as this is a sure sign of osmosis and is quite common on the old water tanks.

George Isted
Contessa 32 "Concerto"
Co32 Class Captain and Measurer.
Back to Top
nardus View Drop Down
CO32 Members
CO32 Members
Avatar

Joined: 07 Jun 2010
Location: Holland
Online Status: Offline
Posts: 57
Post Options Post Options   Quote nardus Quote  Post ReplyReply Direct Link To This Post Posted: 16 Jul 2013 at 9:46am
Same problem here, no need to replace the tank with a rvs one. The rond hatch gives good acces for someone with a long arms. Dry out the tank a few weeks , sand down the blisters and give it few coats of special food grade epoxy. Very important to mix the epoxy thoroughly using a double pot method discribed in :
http://www.epoxyworks.com/18/pdf/tanks.pdf
Ben H
Contessa 32 "Quintessens"
Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down