leaking aluminum fresh water tank

[Manny]

Well, it looks like after 27 years, my 34 gallon fresh water tank gave up after starting the decommissioning process. I had filled it on Thursday and was planning on coming back on Friday to add some bleach and take the boat for a sail and then flush it out, instead I came to find an almost empty tank and a full bilge. Thanks to whoever invented the float switch! Anyway, I'm wondering if there is any reason I can't temporarily seal the aluminum tank with some West System epoxy? The tank definitely has some corrosion which I could scrape out. There is an access port where I can reach basically reach the whole interior and possibly "paint" a sealer in there. I don't use it for drinking, basically just for washing hands, dishes, and brushing my teeth. I'm not sure if there is a toxicity issue with dried epoxy (or aluminum corrosion for that matter) but I just want to get through the season and tackle the replacement in the winter. It is under the v-berth and would require major surgery to get out. I checked the archives but couldn't find a definitive answer.Any thoughts?Thanks in advance,Manny

 

[RichH]

Epoxy will 'do' it temporarily .....

then when you have a chance .... get inside and grind away all the 'deposits', then do a total tank-relining with a FDA/NSF 'lining epoxy' for POTABLE water - ---- DO NOT USE any epoxy inside of a water tank that is not specifically made for POTABLE water .... or the 'leachables' will 'get you'. Lining epoxies for potable water can be rolled-on. You can use fiberglass tape over the internal weld seams. Small quantities of such epoxy is available: www.epoxyproducts.com/nsp120.html .... apply it 'thick', several coats. Why did this happen? You forgot to change the magnesium anode in your water tank !!!! .... or your aluminum tank never had a magnesium anode. ALL metal water tanks **should** have magnesium anodes .... the very same magnesium anodes used on (quality) domestic hot water heaters.

 

[Peggie Hall HeadMistress]

Doing everything Rich recommends

would be more labor intensive and require at least as much surgery to the boat as replacing the tank. 'Cuz if you can open the v-berth to do all that, you can get the old tank out and a new one in. Bite the bullet and check the Ronco Plastics site http://www.ronco-plastics.com for a replacement. They make top quality tanks for a very reasonable price and have more than 400 shapes and sizes...over 100 of which are non-rectangular. And they install fittings in the sizes and locations specified by the customer when they make the tank. It's always cheaper and easier to do something right the first time than it is to jury rig a fix now and do it right later.

 

[Richard Shelby]

water tank

I put a plastic bladder tank inside the old aluminum tank, but cutting open the tank and grinding out the internal baffles was no small task.

 

[Fred Ficarra]

After reading the last post about 'doing it right'

I found myself thinking 'absolutely, totally agree, very logical'. Then I saw who wrote it. Figures.

 

[Peggie Hall HeadMistress]

Fwiw, only glass lined water heaters have

replaceable anodes. If your water heater has an aluminum tank, it won't have one...the mfrs use anodized aluminum. When the anodizing is eaten away, the hot water starts to smell like rotten eggs. Unfortunately, the only cure is a new water heater. Glass lined water heaters cost more, but they last 20 years or longer...vs. as little as 5 years for water heaters that have aluminum tanks.I don't think I've ever seen an anode in an aluminum fresh water tank. Average lifespan is 20-25 years without one.