CapnWil, Thanks for providing us with all your experiemental data. >I devised and fabricated CaptnWils Diesel Tank Bottom Sampling >Contraption my wife will never forgive me either. It is a rigid pipe, >flexible tube affair connected to a Par hand pump. All of this fabrication >was necessary because the Krogen-42 fuel tank is curved to the contour of >the hull, and the fuel inlet is located so a pipe will not go straight to >the bottom of the tank. Somehow in all this I had forgotten that Aftersail is a K42 (1985 model, I think). You may already know this, but a couple of years ago CapnDon of Argonauta, a 1987 model K42, cleaned the interior of his tanks and explained to the assembled masses what he found. First, he let the level in both tanks burn down to a little less than 1/2 full. Then he used the transfer pump to move the fuel from one tank over to the other. Then he opened the inspection cover on the "emptied" tank to start the cleaning. Here's what he found. There are TWO athwartship baffles in the tanks, dividing the tank lengthwise into thirds. If I'm not mistaken, the filler hose is connected in between the two baffles. He said the bottom of the tank was tilted toward the forward end (which is cool - water tends to collect on that end first). However, it means that in order to "suck" the water out from the filler hose, you have to snake your tube past the forward baffle. The baffle design is interesting. I would have thought they would have been solid, with small limber holes on the lower corners. They are apparently made from a solid sheet of iron, BUT the center of the baffle is cut out. The sketch he drew for me showed the the center 50% had been removed. There, indeed, IS a limber hole at the lower edge, but he said there were also limber holes at the other three corners as well. The challenge for your routing of the suction pipe would seem to be to either fish it forward through the lower limber hole OR to try to fish it through the center cutout (that's a MUCH bigger target, but since it doesn't go all the way to the bottom, it may be harder to hit). >2.2 If it turns out that the tank zone below the fuel pickup is never >cleaned by the Polishing System, Ill think about designing a means of >getting to that part of the tank. Here's what else he found. The interior of the tank was covered with a black "sludge" -- about 1/8" thick. He said it would dissolve in water, but not in fuel. He also said he found rust "stalactites on th top of the tank. He also said that there was room for 5 gallons of liquid below the tank drain (the one with the pipe plug in it. I can't recall whether this drain is below the normal outlet or not. If it's level with it, that means that there's 5 gallons of fuel (or water if luck's poor) potentially "waiting" in the lower corner. I think if I ever open my tanks up, I'll try to figure out how to adapt a tube (with an external cut-off valve) to the drain plug and to route that tube directly to the lowest corner of the tank -- then check for water from time to time. Again, thanks for the test data! Cum die... - Bryant Vann M/V Salty Lady, K42 Galesville, MD --> on the Chesapeake Bay