Leaking fresh water tank Grand Banks 46 classic

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Mischa

Newbie
Joined
Sep 13, 2021
Messages
4
Vessel Name
Darkside
Vessel Make
Grand Banks 46 Classic
I have just noticed that the aft aluminium water tank on my GB46 Classic is leaking. I can see a small hole near the front underneath. I suspect that the interior of the tank is quite pitted from corrosion and it may start leaking in other places soon. As the tank is under the generator, I would prefer not to have to remove and replace it, and am therefor interested in a solution posted by CKS using Alumiseal by IMCO.

My initial question is..can someone give me some idea of the internal construction of these tanks? ie: The positioning of baffles, if any etc. I am trying to work out where the best place is to cut an access hole that will give me full access to the interior bottom of the tank.

I would also be interested in any other suggestions anyone could make.

Thanks
 
You might try the easy way out.

Since it is under the gen set which will need to be rebuilt or replaced eventyaly.

A tooth pick pushed into the leak covered with your favorite tube epoxy will work till the next few leaks begin.

Might be a decade , but tube epoxy and tooth picks could solve the problem long enough.
 
I'm going to simply try and plug the holes with Selleys KneadIt Aqua to give me some time. Then I guess the next step is to create some inspection hatches to see if there is anything else I can do
 
Sorry to hear about your leak. I feel your pain.

Send an email to GB Malaysia. (skip Stewart FL) I have been communicating with them regarding my tank issue. They are very responsive!
Request a mechanical drawing of the tank. Send a pic of the tank info plate.

There are a variety of products on the market that might work.

Aluminum and stainless steel alike or passive materials difficult to adhere..

I have spent the better part of the summer trying to fix the pinhole leak in my tank. If you can see the leak and get to the leak from the outside, count your lucky stars.

In my research I found a number of materials that are NSF rated for portable water. Note: food safe is not potable water safe. whatever you must be NSF rated.

JB Weld makes a product called “Water-weld”. You need to significantly scratch the surface with a grinder to make sure the aluminum is not smooth. Find a 1”sq. piece of aluminum to act as a patch. Significantly rough up the inside edge of this “patch” as well.

Clean both surfaces with MEK or acetone. Mix the JB Weld thoroughly, press against the pinhole. Press and slightly rotate that 1 inch plate to insure the expo you gets into all the crevices, sandwiching the JB Weld. That should work.

JB Weld did not work for me and my tank. I am working on the inside of the tank through an access hole. I find the material hardens way too fast for my liking. Got to get it done in five minutes or it’s game over.

After spending all summer on my project, I believe the best product I have found is manufactured by Belzona P/N 1111. The product looks to be the right choice. It’s made for the application. I’ll have more to report next month.

Best of luck to you and keep in touch regarding your results.
 
I have a leaking water tank on a 1996 GB 42. Thinking of using JB weld water on it.
 
Aluminum or SS?
Can you see the leak?
 
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