2004 Yamaha 40HP Motor - Gas?

Is it recommended to run the Gas out of the Engine completely after each use? Or is that necessary? Will it cause any harm by Running gas out of engine completely? (Other than pain the the Pocketbook).

Sometimes the boat may sit up 2 or 3 weeks between use.

Does Yamaha recommend any additives to the gas to keep Carburetors clean and in good order?

[robert graham]

Stabil and Seafoam are both used to stabilize fuel during storage and I use it all the time but use a bit more in the fuel when I know I won't be running the motor for a few weeks or months. I also use the Yamaha Ringfree all the time. These additives with a fuel/water seperator(Walmart $25) and you can eliminate 99% of fuel related problems. Good Luck!

[robert graham]

also, in answer to your question, if you use the fuel stabilizers, then you won't need to run the gas out of your motor between uses. I do occasionally drain the carb float bowls with the 10MM brass hex plug on the bottom side of the carb...very easy to do and then I'm sure there's no junk in them...

[JCONN10]

carb issues

I've had nothing but headaches with my 4 stroke 40 hp 04'. Even after a carb rebuild by 1 shop, and then a carb clean-out by another shop. They are blaming it on Ethanol increase in the gas. Said that it plugged the main jet and the small airways. This all happened after I used the Yamaha gas treatment. I think Yamaha should address this issue. If you can't let your engine sit for 2 to 3 weeks without starting and running normal, then that's a major problem.

[Tony Sopranzi]

F40TLRC - Gas/Ethanol mix

I have an 04 F40 and here in Florida, the hot weather is murder on fuel with ethanol even with water separators. The fuel literally separates in the fuel hose between the separator and the motor in the heat if it sits too long. Its also best to run the carbs dry. Stabilizers and conditioners help to a degree, but the best medicine is marine fuel without ethanol. I've been weaning my fuel tank off the ethanol and as the ethanol-free marine fuel diluted the the ethanol - fuel problems diminished. Our "snow birds" (folks who summer up north) always come back in the fall to a carb overhaul bill. The ethanol fuel seems to store well in cooler weather, but here in Florida its the pits and after a summer of sitting in a very hot garage its a mess - stabilizers and conditioners notwithstanding.
Tony

[ezstriper]

having the same issue with my 06 25 4 stroke, if it sits for a couple of weeks kills the carb...this fuel is B/S !!!!! government need to remove head from a$$

[otto123]

They actually want to INCREASE it from 10% ethanol to 15%

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