Water in Fuel

[Chief Engineer]

live steam (not a powerwasher)....but you still need to wipe down the insides of the tank.

[Chief Engineer]

At least your Coast Guard Tows.....be grateful

[hellosailor]

Clive-
"possibly by cutting a whole in the side to cleanse it."
Generally a bad idea. Holes and tubes and seams and even welds will all eventually leak and then you've got a bilge full of fuel. Your insurer may be upset if a survey mentions it.
Hole in the side...if followed up by a very good welded repair, maybe. But it is always safe to cut the access in the TOP, even if that is a problem because of accessibility. But at least there are access plates designed for a retrofit into the top.

Chief-
"but you still need to wipe down the insides of the tank. "
Not if you invert the boat to let the tanks drain and dry. Or, remove the tanks and invert just them rather than the whole boat.

[Charlie]

Have you ever cleaned a tank with steam? I have had my fuel polished and also taken all of the fuel out of the tank, cut access holes and scrubbed the tanks. The latter was the only one that worked. Mind you the polishing was done by the boat yard and they had just bought the machine and were doing their training on my boat at a huge discount. I still don't see how polishing would get the grunge off of the sides of the tanks. I spent four hours, a lot of elbow grease, and five rolls of paper towels to get my tanks clean.

If anyone has experience with steam cleaning I'd like to hear about it.

[DeepFrz]

I have seen holes cut in the side of tanks on a power boat where there just was no room at the top of the tank. It was sealed with a very well made tank access port. Sometimes there are just no other options.

[Bill_E]

I had my fuel pumped and tank cleaned by a professional outfit in Florida but mainly all he did was agitate a bit and vacuum out fuel then agitate some more and vacuum. There was only about 8 gal of fuel and it looked awful so we discarded it. Later, in the Turks and Caicos we had to remove the tank to do some work under it so we pumped the fuel through filters into a plastic 55 gal drum. Removed the tank and cleaned it well with a pressure washer, upside down, on its side, etc. and let it dry for two days in the sun. I have a very small access on the top of the tank, large enough for a pressure washing wand but too small to get your arm in there. Then we replaced the fuel by pumping again through filters. I'm glad we got the opportunity to clean it well. Since then I've been even more careful to filter fuel and add a bioagent.

If I understand correctly, bacteria and algae can grow in the fuel, even in the dark, and when they die they sink to the bottom. I don't think that they are "attached" to the tank itself but they tend to clump. So when agitated in rough seas and bad weather the clumps start floating around and cause all kinds of problems.

I'd look very carefully to see if it is possible to remove the tanks. Although mine was a pain to get out, I found that cleaning it on the dock was a lot easier than working in the cramped quarters below deck and breathing the inevitable fumes.

[hellosailor]

"I still don't see how polishing would get the grunge off of the sides of the tanks. "
It won't and can't, that's why it is fuel polishing--not tank cleaning.

[wilsodf]

Make sure you use some sort of Biocide to kill the bacteria. After you polish the fuel, add some of this and it will keep it from happening again. I have used Killem with great results. Some water in your tank is going to happen and this product will keep things from growing in it.

FPPF

[Cap]

Originally Posted by hellosailor

"Any ideas on how to clean the fuel and tanks? "
You pump it out, allow it to stand and the water will separate out. Pump the fuel into a clean container (or wait until the tank is cleaned then put it back)and dump the rest with your waste oil.

Tank cleaning? All depends on access. You may need to remove the tank from the boat, scour it and tumble it, or have a radiator shop steam clean it. Get inside and get the crud out, leave it in the sun for a day to dry nicely, then reinstall and put the fuel back in.

For ongoing maintenance, you can install a fuel filters (or filters) and a pump in a loop, so that it sucks fuel from the tank, filters it, dumps it back it, and then change that filter instead of waiting for the primary to clog. Many options, many old threads on the topic of fuel polishing and the like.

Hi All,

I'm looking into building my own fuel polishing system; either internal, or a mobile one, but could use some advice with regards to hardware. I have two 13hp Nanni diesels and would like to know the best pump and filters to use to set up the polishing system. Any help would be appreciated.

Thanks...Jeff

[Honey Ryder]

buy some spare filters, take her out on a rough day and run for a few hours, change the filters when they get clogged, then do it all again a few more times. treat new fuel with a good bug killer. or, get some friends over and try rocking her from side to side as aggressively as possible. try and stir up the crud on the bottom. it might work depending on how much is in there. i got my tanks clean by using her in rough seas, and by having plenty of spare filters to hand. make sure you know how to change your filters before you head out...

[motion30]

hellosailor
The theory is the clean fuel is pumped back into the tank at high volume and pressure this is suppose to knock the goop off the inside of the tank In actually NOT I think If you could design a tank with a spary bar inside this might be possible
I have found running my boat in the rough water helps break the gunk up while also killing the motor