Water in fuel tanks???

[tonigerl]

Greetings, New member here. I have been having trouble the past two years with fuel in the tanks of my 78 Challenger jet boat. The first year the tanks were full and in spring half or better was water in spring. The next year the tanks were down about half and the same thing the following spring. All looks sealed and tight. Any thoughts on why this may be happening? We are getting ready to use it again and hope for no water this time but would like some advise on what to fix.:confused:
Thank you very much for your info.
T

[jetboatperformance]

For extended layup,we store our tanks either completely full (with Stabil) or completely drained dry.Partialy filled tanks will "sweat' inside like a "cocktail glass" and moisture contamination will occur. Also the "shelf life" of modern pump gas is very short (only a couple months) Ive been told the alcohol in it will actually attract moisture. You might also take a good look at the type of deck fills you have,some of the old flush mounts dont seal well and are suceptible to water intrusion Good luck Tom

[tonigerl]

Tom, Thanks for the info. We will be taking a look at it in a couple of weeks to prepare for summer and see what the situation is.
Toni

[TahitiTiger]

my boat has an electric booster pump on it and a fuel water seperator. At the end of season I disconnect the fuel line, flip the ignition kill switch, and let the booster pump suck the tank dry. Fortunately every time I have pulled my boat out for its first run, it always starts right up after priming, and no water drains from the seperator. :D

[SmokinLowriderSS]

Tom pretty much hit my concern. Sounds like way too much water entry for condensation. Double-check those fills. I have never had the problem, but I have a flush fill on the stern, and it closes against an o-ring and seals very well.

[kp216]

Ive been told the alcohol in it will actually attract moisture.
Tom - The way I understand it is that gas line antifreeze, such as Heet, is essentially alcohol (methanol), and the way it works is that water is attracted to it. The methanol then suspends the water and lets the engine burn it.
I run quite a bit of ethanol blend through mine and have never had a problem with water in the fuel. I don't know if it ethanol works the same. Maybe I've just been lucky?
As far as long term storage, I do the same as you. Full tank with Stabil. I disconnect the fuel line to the carb and pump fuel into a five gallon jug and dump back into the tank. When I'm sure the Stabil is fully mixed in, I then reconnect the carb and fire the engine to get the treated gas into the carb.
As far as the original question, I'm thinking the same as the others: That amount of water is not from condensation and is getting in there some other way.

[wright27]

Just siphon or get a hand pump and remove the gas when your not going to use it. Put the gas in a can then put it in you truck. When the new season starts put some Heet in fill the tanks and go. I do this every year and have never had a problem.

[396_WAYS_TO_SPIT]

Tom is on the money with this one;) My Kachina used to get water in the tanks all the time! Make sure that you have a fuel water seperator. Also, check the caps. The old school pop up ones are prone to leaking. Go with the flush style caps and they will seal better for you;)
_Spitter