Fuel Tank Revitalization

[akswimdog]

Greetings,
Does anyone know if there is a procedure/process out there that will revitalize a couple of old (20 years+/-), approx 50 gal diesel tanks? They are currently holding fuel and installed so I don't know the full extent of any corrosion but are showing signs. I will either be revitalizing these or buying new ones so right now I'm exploring the options available. Any similar war stories would be greatly appreciated- Thanks!

[SailingwithSoul]

Originally Posted by akswimdog

Greetings,
Does anyone know if there is a procedure/process out there that will revitalize a couple of old (20 years+/-), approx 50 gal diesel tanks? They are currently holding fuel and installed so I don't know the full extent of any corrosion but are showing signs. I will either be revitalizing these or buying new ones so right now I'm exploring the options available. Any similar war stories would be greatly appreciated- Thanks!

Hi akswimdog, Wolcome to CF

A few more details would be helpful. What is the condition of the fuel? What "signs of corosion" do you mean. I had to to do something similar on my boat. She went under before I got her. My tank is a 25 gallon aluminum tank. I bled all my fuel lines, replaced all my filters and pumped out 35 gallons of dirty fuel. (on full tank, and one half tank of recently added and sloshed around diesel. Afterward, I wiped the salt and green corrosion of the tank with metal cleaner, and she has been working like a dream. Just carry some extra filters and you should be good to go.

Here's a pic of my fuel when I was pumping it out along with the link to my blog entry.


There's orange juice in my fuel tank!

Cheers & happy Sailing!!!!

[akswimdog]

Thanks for info SWS- The fuel is "okay" but we'll be pumping it out soon as currently there is inadequate filtering. Both tanks are showing corrosion on the outside. I've tried to upload a photo but not sure if that will come through... Again thanks for the info.

[Sailmonkey]

Originally Posted by akswimdog

Greetings,
Does anyone know if there is a procedure/process out there that will revitalize a couple of old (20 years+/-), approx 50 gal diesel tanks? They are currently holding fuel and installed so I don't know the full extent of any corrosion but are showing signs. I will either be revitalizing these or buying new ones so right now I'm exploring the options available. Any similar war stories would be greatly appreciated- Thanks!

If these are steel tanks, the only way to "revitalize" them would be to remove them, sandblast them externally and paint them. If they're corroded inside, you'll need to replace them. There is no magic cure for this.......sorry.

[akswimdog]

Thanks SM- I think deep down I knew what I needed to do (replace them) but just wanted to explore the possibility....Thanks again for participating. Best Regards-

[Cheechako]

It appears they may be aluminum...? Usually the only issues with Alum is any chafing.... like screw or nails protruding on the supports they rest on. The tend to work loose over time and start rubbing on the tank. You'd really have to pull them out to know. They could be minutes or decades away from leaking.....

[akswimdog]

Exactly- and its that uncertainty that I'm not comfortable with...Furthermore if I have to pull them anyway, at which point I still may not know the extent of degradation on the inside of the tanks, I may as well put good money to good use and just replace them...At which point I'll know exactly what I have right from the start. Seeing what I can see now on the tanks I'm thinking there's no point in throwing "exploratory" funds at these. I appreciate your response and helping me confirm and solidify my direction. Best Regards!

[Florida Mike]

You might go ahead and cut an inspection holes and look inside and to see what I problems you have. It appears that you draw your fuel off the bottom of the tank, that in my opinion is the best place to keep good clean and water free fuel as long as you have a good water separator/filter system.
You might take a look at; http://www.caswellplating.com/restoration-aids/epoxy-gas-tank-sealer.html
I have no connection with these people, I just read about it in another thread somewhere. Just my two cents, Mike.

[Irish rambler]

askimdog. If I may be so bold as to add my pennyworth to the other posters. I did a similar job and replaced my tanks with 316 S/Steel, I asssume up in Alaska you will get condensation in the fuel tank, one point I cannot stess strongly enough is that you should have a sump drain valve fitted to each tank so that you can drain off any water/sediment easily, if you keep the water drained regularly from the fuel you will prevent diesel bug, a standard water separator and main engine filter will be sufficient to ensure reliabilty. Prevention is better than reparation.
I hope this helps.

[Cheechako]

Not sure how hard they are to get out, but it might be worth removing, inspecting and painting them so you know what you have. It appears you draw fuel from the worst part of the tank where the water and muck reside. I guess that could be good or bad... you always know if it's clean I suppose!

[akswimdog]

That's great advice- I'm not sure I can afford doing the SS but the clean out option you mention is very well taken!! Thanks very much for the contribution!! Best Regards!

[akswimdog]

Originally Posted by Irish rambler

askimdog. If I may be so bold as to add my pennyworth to the other posters. I did a similar job and replaced my tanks with 316 S/Steel, I asssume up in Alaska you will get condensation in the fuel tank, one point I cannot stess strongly enough is that you should have a sump drain valve fitted to each tank so that you can drain off any water/sediment easily, if you keep the water drained regularly from the fuel you will prevent diesel bug, a standard water separator and main engine filter will be sufficient to ensure reliabilty. Prevention is better than reparation.
I hope this helps.

Excellent advice! I'm not sure I can afford the SS but the concept of the sump is very well taken- Thanks for the contribution!! Best Regards!

[Pblais]

I'm not sure I can afford the SS but the concept of the sump is very well taken-

There are no known algae that can live in fuel but they all are happy in water. It's in the water that they grow and in the fuel that they die and cause your problems. They get in from the the air via the vent. If you live is fluctuating temps then you will get water in the tank. Condensation can't really be stopped. You can do things to help minimize it but I like the sump idea a lot for Alaska. You just have to know the water will be there no matter what you do. If you heat the cabin then the temps go up and down and that means condensation big time!

Installing a sump isn't trivial on some boats. I'm fortunate enough to be able to haul all my tanks out the companionway. My aft SS fuel tank was so bad we have to haul it out and steam clean it. Stainless tanks are really nice but the crap inside them still can be a problem in all tanks. Inspection ports and sumps just makes the job of cleaning tanks easier.

[Roy M]

Or..... you can build your tanks out of plywood, sealed in epoxy resin. You can then install the baffles where you want them, install a dipstick AND a fuel gauge sender, fuel pickup, vent and filler fixtures, and then install BIG cleanout ports to make life easy when you want to have clean fuel tanks. My tanks are about 28 years old now. The last time I drilled a core out (to install the fuel gauge sender) the plywood core smelled like the day I built it. I added graphite powder to give the tanks a cool looking black plastic appearance. You can use other colors if you like.

Cut the plywood and assemble using generous epoxy/thickener fillets (beer can radius is perfect). Epoxy seal the insides and outsides. You can add fiberglass tape if you wish, but not necessary. Install the baffles, then add the top, with its access holes, reaching inside to apply the fillet joints around the inside top. Secure the access plates with machine screws into oversize drilled holes filled with epoxy graphite and waxed machine screws to act as release agent. Insurance companies have accepted this as a "composite cellulose-core construction". Gougeon Brothers, developers of West System epoxy, came up with this technique almost thirty years ago, and it's been used by many boats with great success, Here are some pics:

[akswimdog]

Those are real beauties! I appreciate your industriousness...I don't think I'm going to have the time to commit to your extent in this endeavor but you obviously outdid yourself as evidenced by your recent testing. Thanks for sharing the concept- It must have been a bit of a time consuming project but it looks like they paid dividends. Best Regards-