Converting Diesel Tank to Water??

[sunbear1]

I have a steel sailboat with a 94 imp. gallon or 427 litre tank now in diesel. Any thoughts about converting it to water?? It is made out of uncoated inside 1/4" mild steel. Should I not bother and just leave as diesel and install other water tanks--have about 35 gallons now. I was thinking more water would be a good idea. Have a Yanmar 3GMF. Thanks, MarkH

[Caracal]

I wouldn't bother attempting to convert those tanks into carrying potable water. Get some new ones done instead.

[rebel heart]

I chopped the top off my diesel tank and use it for storing beer, laundry detergent, dive weights, and other heavy stuff. It was about seven months ago that I did that and anything that goes in there still stinks like diesel.

The odds of having any practical way to not have your water taste like diesel for at least the next five years is minimal.

[Cotemar]

I have seen these threads before and wonder why would anyone think this would be a good idea. NOT !!!

Clearly they are not thinking.

Waiting to see a thread where someone wants to change the sewage tank to drinking water. REALLY

[cheoah]

You definitely need some more water tankage, but don't use that tank. I would think a poly tank would be good for that area, since bilge water would not really be an issue like it is with mild steel or aluminum - maybe even more so in a metal boat.

Bladder tanks might be a good option too. Bumping up to 125 gal water total will be a really good improvement.

[Cheechako]

It looks like you can get that tank out. You could take it to a shop and have about half cut off and a nnew end plate installed. Then ut a new water tank forward or aft of the half you keep.

[rwidman]

If you convert your fuel tank to a water tank, how will you make the engine run?

Seriously, don't try to convert a metal tank that once held fuel to a tank for potable water. You will never get rid of the smell and taste and bsides a steel tank will rust if you put water in it.

If you think you need to carry more water, buy one or more poly water tanks. Don't forget that you have to vent them.

[charliehows]

Originally Posted by Cotemar

I have seen these threads before and wonder why would anyone think this would be a good idea. NOT !!!

Clearly they are not thinking.

Waiting to see a thread where someone wants to change the sewage tank to drinking water. REALLY

i can feel the blood pressure rising...

[JPA Cate]

Sunbear,

Jim and I cruised for 18 yrs. on a sailboat that had 50 US gallons water capacity. Yes, it can be done, but I think 35 is really scanty for a long passage. If
1) you have salt water to the galley for dishwashing, and
2) set aside one "sun shower" of fresh water for bathing, and
3) carry one 5 gallon "emergency" fresh water, easily accessible, you could make it work.

However, consider carefully just how much water you presently use, and unless you're by yourself, also how much the other person aboard uses, before you decide not to add another water tank. You can live without food, but not long without water. By the way, backpacking in California will teach a lot about minimal water use. Is there somewhere dryish in BC you could practice in? Conserving water is a skill, and you can certainly learn it if you want to.

[rwidman]

Originally Posted by Ann T. Cate

Sunbear,

Jim and I cruised for 18 yrs. on a sailboat that had 50 US gallons water capacity. Yes, it can be done, but I think 35 is really scanty for a long passage. If
1) you have salt water to the galley for dishwashing, and
2) set aside one "sun shower" of fresh water for bathing, and
3) carry one 5 gallon "emergency" fresh water, easily accessible, you could make it work.

However, consider carefully just how much water you presently use, and unless you're by yourself, also how much the other person aboard uses, before you decide not to add another water tank. You can live without food, but not long without water. By the way, backpacking in California will teach a lot about minimal water use. Is there somewhere dryish in BC you could practice in? Conserving water is a skill, and you can certainly learn it if you want to.

I don't think anyone is trying to convince the OP not to add water capacity, they are just saying that trying to use a former diesel tank for potable water is a bad idea.

[Cotemar]

Absolutely add water, but do not use a diesel tank. It’s just a bad idea.

[Jim Cate]

I suppose that one way to do it would be to fill the tank with diesel, run the engine to charge the batteries, use the electrical energy to run a RO desalinator and have LOTS of water. Might be easier to change out the tank...

Cheers,

Jim

[Blue Crab]

Originally Posted by sunbear1

I have a steel sailboat with a 94 imp. gallon or 427 litre tank now in diesel. Any thoughts about converting it to water?? It is made out of uncoated inside 1/4" mild steel. Should I not bother and just leave as diesel and install other water tanks--have about 35 gallons now. I was thinking more water would be a good idea. Have a Yanmar 3GMF. Thanks, MarkH

I don't understand how the OP would consider this, given he was clever enough to get a big nice boat together.

[sunbear1]

Actually this is quite a reasonable idea--as I said the tank is 1/4" mild steel. You can sandblast and hot dip galvanize or epoxy coat after sandblasting. One could also have the tank caustic dipped or as I have found out today--some places now have ovens in lieu of chemical stripping. There will not be any "taste" issues after that. The idea is pretty reasonable since I have a 100 gallon tank that is now diesel and don't want a diesel tank that large but would like 100 gallons of water and I have a poly diesel tank of about half that that will fit elsewhere easily. Anyway I am sure something will come to my mind. But will investigate a bigger poly water tank as well. Economically, what is cheaper--modify the existing or buy a new tank--that's all it comes down to. Thanks for the input.

[rwidman]

Originally Posted by sunbear1

Actually this is quite a reasonable idea--...........

If you think this is a quite reasonable idea, go ahead and do it. I don't know why you asked for advice if you're going to ignore it.

But if you convert your feul tank to water, how will you fuel your engine?