September 29 - October 11— Three Work Days, The Contaminated Tank Fixed — Almost

    About two or three years ago I accidentally contaminated the larger of our two new aluminum fuel tanks, the more forward one, which is larger. Yes, again, I put the water hose in the fuel tank!!! I knew that not a lot of water got in but I did not know how much. Turns out it was probably only about a cup of water,  because I realized that I was an idiot and yanked that water feed hose out of the diesel deck fill. But because water is heavier than diesel it will tend to lay on the bottom of the tank and be sucked up first. It will overpower the filters and shut off the engine. And what can go wrong will go wrong so such an incident is likely to happen at the most inconvenient time, like when no sail is up and we are in a narrow passage with strong current and wind. So since my idiocy, we have simply not used the larger of the two fuel tanks. 

During this summer when we needed fuel I used the battery operated liquid transfer pump that I inserted into the green plastic capped hole to pull diesel fuel out of the contaminated tank into an empty clear plastic one gallon water bottle. Diesel is pink and water is uhm, water colored, so I looked to see if there was water  in the bottom of the bottle, and finding none, used a second safety check by pouring the diesel through a Baha filtered funnel into the green plastic covered fill hole of the “good” aft tank. I don’t know how it works, but the Baha filter lets through diesel but blocks water. I did this about thirty times.

By the end of summer the remaining fluid in the “bad” tank was so shallow that the pump did not draw fluid  up but sucked air. It turns out that just a little more than a gallon of fluid was left, but it contained the water, and a lot of aluminum filings and slivers.

As soon as we got hauled on solid ground, with no rocking, it was time to try to get that tank bone dry. This  involved removing the twelve nuts that hold the gasketed viewing port plate to the top of the tank. The plate is about 8 inches square. Then I was able to use what are called diesel diapers to mop up the gallon. Those white wipes absorb diesel but not water. Taking a wad of them in my rubber gloved hand and dipping it into the tank I pulled it up sopping wet and pink and squeezed the diesel into a five gallon bucket. After many such handfuls, the tank was dry, at least on the side where the viewing port is located. 

But the tank is baffled; it has an aluminum plate welded to its sides, with a semicircular opening at the bottom. This plate almost divides the tank in two, but permits the fluid to flow from back and forth between the halves of the tank, but slowly so that its weight does not bounce the boat around. And as the tank’s bottom is slightly lower on the other side of the viewing port, the last bit was on the “wrong” side of the baffle. So I had to invent a tool, well it is not that original: a mop. I had an 18” length of 5/8” dowel which I had inscribed on both sides with the depths of the two tanks to use as a dip stick fuel gauge. Wrapping the diesel wipes around one one and securing them very tightly with a hose clamp, I had my mop. With elbow at the bottom of the tank, my forearm reached the hole in the baffle and the mop, repeatedly inserted through that hole into the deeper end of the tank, flopped around and withdrawn, pulled out the remaining fluids out, to be squeezed into the five gallon bucket. 

The tank is dry, awaiting to be filled with 40 gallons of diesel next spring. But the job is not quite done, just “almost”.  The remaining problem, which I believe is solved, but not implemented, is the three missing nuts in the photo. They are not missing in the sense of lost, but I have not been able to catch the top thread of the bolts (which can be seen in the photo). The bolts pass through rubber strips both above and below the top of the tank — so they don’t fall to the bottom of the tank. But how to raise them to catch the nuts onto them. The sleepless night ended with another tool. A simple “L” shaped “angle iron”. If inserted through the green plug, I’m thinking I can use the horizontal part of the “L” to push the bolts up from inside the tank. I will keep you informed.