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Water in Fuel Tank - DIY

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  • Water in Fuel Tank - DIY

    I thought I would share my weekend saga so other could possibly learn from it should it happen to them.

    While wakeboarding with my 04 Super Air fully loaded with ballast (2500 lbs) plus 3 people, I took a sharp left-hand turn (sharper than normal as the rider wasn't ready for me to turn and I had run out of lake). Out of the turn the boat immediately started running REALLY rough. The engine was vibrating and skipping so much that I though maybe I had hit something and bent the shaft, but there was no impact so that couldn't have been it. I powered down and back up to see what would happen and the boat sputtered but got back up to full power and ran smooth so we headed home which was only about 30 seconds away.

    I had to leave shortly after that and didn't see the boat until this past weekend. Hopped in it and right off the bat ran REALLY bad. Knocking, skipping, shaking etc. After changing out the cap/rotor/plugs it was pretty clear it was bad fuel. I drained the fuel water separator and started the boat, ran good for about 30 seconds then really rough again. Repeated this process about 4 times realizing the separator was full of water ever time almost immediately which meant there was A LOT of water in the fuel tank.

    I took the fuel sensor cap off and siphoned about 6 ounces off the tank bottom. The sample was about half water. I got a 5 gallon bucket and took the fuel line for an small outboard motor, cut the connectors off the end so I was left with just the rubber lines and the primer bulb. Pumped about 2 gallons of water/fuel mixture out of the bottom of the tank. Pumped a small sample into a clear cup to see my progress, still water in the fuel. Took about another 2 gallons of water/fuel mixture out. the next sample was totally free of water. Put everything back together and the boat was back to running like a champ. All in all there was about 2 gallons of water.

    For a problem that had the engine running so horribly, the fix was relatively easy with the right setup. My hypothesis is that I dunked the overflow valve in the turn in took a gulp of water. What doesn't make sense is the amount of water I took out (2 gallons of so) and the fact that I've had more weight in the boat before, even all on the port side for surfing and never taken in water before. Maybe I got a bad tank from the gas station?? BUT the engine didn't run rough until about half way through the tank...? So I'm not sure how I got so much water, I just hope it doesn't happen again.

    Some Tips (these may be obvious but figured I'd throw them out there).
    Turn off everything in the boat and remove the batteries to eliminate any chance of a spark. It may take extra time but the flip side could be dire.
    Water is heavier than fuel so it will be at the bottom of any sample and the fuel will float on top, it's very easy to see the division in a clear glass.
    No smoking.
    Don't water down your fuel

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      I agree that you can't two gallons of water from the vent during one turn. You should really keep a close eye on this in case it wasn't bad gas and something else is going on. One way to check for water in the tank is to use water finding paste for petroleum products and dip a stick with paste in the tank. If there is any water, it will show up on the stick with a bright red color.,4389.htm