Water tank painting

[Emerald Fox]

Hi again boaty folk!

 

Are there any old threads about this, or new advice? In the front of our new(old) first narrowboat there's a large steel plate with many largish bolts around the edges, and recently the previous owner told me the water tank is below that plate, and that he last had it opened 5 years ago when he painted the inside of the water tank with a "special paint".

 

I thought I'd like to open that plate and have a peer in, with water all run out. There might be deposits at the bottom that could be sucked up. I don't even know how water gets from the tank to the water pump - presumably a pipe, but is there a filter in the water tank where the pipe starts? (that's a rhetorical question).

 

How often should the insides of water tanks be painted, and just what are those "special paints"? And how does one go about this kind of work?

 

Thanks again... EF

[JDR]

The first part of the job is to remove any loose rust and prep the surface of the tank for painting. This is not difficult in itself but the job is invariably made a lot more difficult due to restricted access. You could use scrapers then vacuum loose rust from the bottom but I would urge caution if you try and use power tools in such a confined space. Some people use bitumen paint (same as you would use for the hull) but only if it is described as potable (ie drinkable). I used several coats of Vactan which is safe for domestic water systems. Whichever paint you use the longer you can let each coat cure the better. I bought a heat gun to help cure the Vactan and this transforms the job from a week for three coats to dry properly to 48 hours. After five years it is certainly time for a look, when I did my tank which is internal to the bow the rust looked horrific but after a couple of days cleaning I was relieved to find the tank in very good condition. I would also recommend finding some method of plugging the exit hole from the tank to avoid any loose rust or debris entering the system during cleaning. It is not a pleasant job but satisfying to know the state of the tank you are drinking from. Good luck.

[Ex- Member]

If I ever had a boat with similar tank I would only consider 2 options.

 

Have the inner tank shot blasted and paint with a couple of coats of 2 pack paint such as Jotun.

 

Or Thoroughly clean area and use a rubber/plastic type tank liner

 

Other options are available, but I wouldn't choose them personally.

[dmr]

Its an unpleasant job so you don't want to do it often.

If you plan to keep the boat for a long time then best to take the tank back to bare metal. You just might be able to find someone to shot blast it, otherwise a wire brush in an angle grinder should be ok.

Then paint with a suitable epoxy. Have a look at the Reactive Resins website.

 

...........Dave

[Dekazer]

Hiya,

 

I don't know if you found this recent post, but it has some detailed advice: http://www.canalworld.net/forums/index.php?showtopic=68040

 

Lucy