Re: Syphoning gas from 1991 Four Winns 200 Horizon
Empty gas tanks condense moisture.
Not according to this guy.
The Myth of Condensation in Fuel Tanks by David Pascoe: Boat Maintenance, Repairs and Troubleshooting and because I have actually studied physics and thermodynamics I understand his explanation.
And I have done exactly the same thing (left my tank either empty or 1/4 or less [EACH YEAR] for more than 20 years and have NEVER gotten condensation. (never gotten it in an aircraft fuel tank either and THEY are far more exposed to temp swings than any marine fuel tank) AND I have never in all those years used Stabil or any other fuel "stabilizer"
There is no fuel snake oil that will prevent water from collecting in your fuel tank (see the article above for possible sources of fuel tank water)
The only sure way to siphon fuel (and other contamination) out of your tank is to remove the gage sending unit and use a hose. I use a clear vinyl 3/4" hose (Home Depot or other hardware store)
Since most boats have a fitting at the tank for the fuel-fill hose, the sharp bends and fitting can frequently prevent you from being able to get a hose to the bottom of the tank to effectively siphon the fuel And you cannot move the hose around to the corners etc to get the other "stuff" in there (if present)
I use a length of hose long enough with a 1 or 2 ft long piece of plastic PVC pipe on the end to use as a vacuum "nozzle-end" to move around in the tank to get all the debris.
At the fuel receptacle end of the hose (on the floor), I connect a 3/4" ball valve so the helper can close the valve to switch to an empty fuel receptacle without spilling or losing the siphon. Closing the valve at bottom of the siphon, you can fill the hose completely before starting the siphon (and
not have to use your mouth!! [
DON'T DO THAT!!!])
DO ALL THIS OUTSIDE away from the garage/house! and WITH PLENTY OF VENTILATION! Have a (Dry Chem/Halon) fire extinguisher handy............and of course, NO SMOKING!
If you're going to pickle the engine and leave it for more than a year or so, you should probably run the carb dry. I have actually let my boat sit for 2 full years with an empty tank without draining the carb, and just filled the tank, replaced the filter and had no problems getting it running once the fuel system was primed.
Otherwise for normal storage run out or drain out as much fuel as you can (1/4 or less tank) , park the boat in FALL, and in Spring, just fill the tank, replace the filter and get it running with the new fresh fuel and go boating!
The biggest problem with old fuel is the loss of the "higher-end" hydrocarbons due to evaporation.
NO FUEL SNAKE OIL CAN PREVENT THIS........ the only way to prevent it is to pressurize the tank. (Have you ever noticed the hissing sound when you remove the fuel cap on your car?) Boats do not have pressurized tanks (yet!!!!)
The BEST way to mitigate old fuel (loss of vapor pressure) is to dilute it with as much fresh fuel as practical.
boat was NOT run last year so it sat out a season and has run like crap all season. I was blaming plugs? Carb again? It starts hard and sputters a lot until real warm.
You might want to check your fuel tank pickup & screen, anti-sphon check valve, filter, pump and automatic choke. As a last resort, you might also check your carb fuel bowl. You may STILL have contamination.
ymmv,
Rick