Leaky Diesel Fuel Tank - Fix or Replace?

[RLaird]

I may have missed it but...
You should have a pressure test done to assure that you are barking up the correct tree. Not challenging to assemble and might find a different culprit.
Just a thought

[Group9]

Originally Posted by wsmurdoch

We did the same when our aluminum diesel fuel tank began leaking in the Bahamas. When we replaced the tank a year later, we found the repair to still be in perfect condition.

March 18, 2018 https://irish-eyes-to-the-bahamas.blogspot.com/2018/

February 15, 2019 https://irish-eyes-to-the-bahamas.bl...&max-results=7

Ironically where ours happened, too. We did the repair tied up at Nassau Yacht Haven Marina. .

[Newport]

Having just replaced my fuel tank, things I found out!
Check the Transport Canada website as to replacement requirements, type of material, stickers identifying who built, material
Then there is all the requirements for installation!
I would check this out BEFORE replacing, because it sounds like you might have some issues if you were going replace it and meet the new standards they have implemented. My surveyor knows I had to replace tank so he pointed this out to me. To get a survey I have to follow. Look out and have fun

[piebuss]

We went through a similar process last year (hm... actually, it was 2019, but last year doesn't really count I recon).

Our 200L aft tank has lake since we bought the boat, and after 4 years just running off the other 2 tanks, I decided to pull it out and replace it.

Getting it out was a mission, but I'm really glad I did before ordering a new one, because the tank was actually fine. There was a pin hole in the pipe that threaded into the tank, which we could not access with the tank in the boat.

Having the tank out gave us a chance to do a deep clean, starting with boiling water and detergent until it was spotless, then several rinses with boiling water, and finally several rinses with alcohol.

It's so rewarding when you plan to spend $$$, but get away with just a good clean and relaxing some minor parts...

[captlloyd]

Originally Posted by Newport

Having just replaced my fuel tank, things I found out!
Check the Transport Canada website as to replacement requirements, type of material, stickers identifying who built, material
Then there is all the requirements for installation!
I would check this out BEFORE replacing, because it sounds like you might have some issues if you were going replace it and meet the new standards they have implemented. My surveyor knows I had to replace tank so he pointed this out to me. To get a survey I have to follow. Look out and have fun

I definitely would not do that. The expression “ let the sleeping dog lie” comes to mind.

[contrail]

Triple M Plastics, in Maine, make custom plastic tanks quite reasonably. Many older Leopards have had leaks in their tanks and replaced them with plastic ones from Triple M, quite successfully.

[Mike Banks]

Plywood epoxy lined fuel and water tanks work fine--many have used them with success.

If unsure, you can make a wooden enclosure and line it with a bladder--that also works for water tanks.

I used a carpet-covered restrained compartmented rack containing 20 litre diesel containers and a 30 litre day tank, and a transfer pump to fill the day tank from the containers.

So EASY to get fuel from the tender and hoist it aboard where there are no fuel dock facilities--and the same system was used for water. If you do get a leak--you have only lost a small amount of your fuel or water--but I never had any leaks.

In a small vessel I would not use anything else. In remote places, getting fuel or water aboard will always require containers--so why not make them the tank?

I have even used this system for holding macerated black sewage. Two double opening screw tops twenty litre containers with carbon filtered breathers, pre-charged with sterilant solution hold quite a few days of use where ocean discharge is prohibited.

However--in some places I doubt this system would be approved, many places have regulations requiring sewage holding tanks to be of the shore pump-out, not human disconnect tank and carry out type.

And yet they seem to think Casette camping types and composting types are OK--so beats me.

[MicHughV]

This could be a thread of it's own....traveling the US and Canada, one is pretty much assured of a clean quality diesel product..but travelling abroad is not the same, especially in out-of-the-way places. Diesel may arrive by tanker truck, dirty 40 gallon steel containers, water contamination and other iffy sources with little or no thoughts or warranties as to quality or to price per gallon and as the above has pointed out, you may have to schlep the stuff yourself from some source.
Getting back to the OP's problem, many possibilities for repair/replacement exist, all viable in one way or another, it pretty much depends if you have DIY skills or require someone else to address the problem.

[girdasso]

My aluminium diesel tank is now 32 years old and still going strong but it is mounted high up clear of bilge and moisture. In your case removal and repair of SS tank should be the cheapest option but make sure it is mounted clear of bilge water, moisture, and electrical currents.

[wsmurdoch]

Originally Posted by Group9

Ironically where ours happened, too. We did the repair tied up at Nassau Yacht Haven Marina. .

As you saw in the links, we were in Palm Cay Marina and used their free loaner car to drive into Nassau to buy the West Epoxy and glass cloth to repair the leaky fuel tank. Had I known that the epoxy repair would have no deterioration after a year, I would not have bought a replacement tank. As it was, with the new tank installed, it broke my heart to throw the perfectly usable old tank in the aluminum recycling dumpster.

[Group9]

Originally Posted by wsmurdoch

As you saw in the links, we were in Palm Cay Marina and used their free loaner car to drive into Nassau to buy the West Epoxy and glass cloth to repair the leaky fuel tank. Had I known that the epoxy repair would have no deterioration after a year, I would not have bought a replacement tank. As it was, with the new tank installed, it broke my heart to throw the perfectly usable old tank in the aluminum recycling dumpster.

Once I found out that West System epoxy can be used to build a diesel fuel tank from scratch with, I knew it would be great for a repair of one. We were able to just walk across the street to Lighthouse Marine to buy everything we needed!

And, like you, I think a repair like that is about as permanent as you can get, if you wanted to leave it like that.

[and4ew]

Thanks all for the advice and comments, as well as the experiences. One poster said it would be cheapest to repair the existing tank. I agree but I would always doubt its integrity.



Another poster said 70 litres was not much for coastal cruising. I'm interested in this because 70 litres at 1 litre/hr at 5 kt is a long way and a long time. When I had a gas engine I'd use less than 100 litres all summer. Am I being overly optimistic?


The comments about using fibreglass to repair a tank are very useful! I would not have thought of that and although I hope to never have to do it, the fact that it can be done will bring piece of mind.

[gonesail]

if you do replace (which you should) .. it is a good idea to build a mockup with plywood to make sure you can get the tank where it needs to go.

[Compass790]

Originally Posted by Lepke

Whether you fix your current tank or have another built, apply a diesel tank coating to the inside and the tank will outlast the boat.

As usual I agree with Lepke.
Any epoxy meant for tank lining will do.
We have a 1980 ss tank that doesnt leak & its had heaps of water in it. P.O. had no o-ring on the deck fill cap!



We have a 20 litre tank for coastal cruising at 600cc per hr fuel consumption & carry another 20 litres but really the 20 litres fuel jug is just for when we go into port to buy food, booze & diesel & we dont go into marina fuel docks.
Depends on your sailing/motoring ratio i guess

[skenn_ie]

Originally Posted by Bowdrie

Stainless steel has seldom been the best choice for diesel fuel.
In the "old" days of high sulfur fuel, any water in the tank, (which migrates to the tank bottom,) would react with the sulfur, creating sulfuric acid, which attacks the welds.
The stainless is OK,, but when it is welded the welds are susceptible to corrosion from the acid.

Stainless work hardens very quickly too, accelerating the failure along sharp corners. I plan to get stainless tanks made, but with rounded corners, and the main seam along the top centre, not near a corner. My tanks will be big enough to get inside too, so welds can be pickled inside as well as out.