Trouble starting?

[jloomis]

i have a 97 yamaha pro vmax. the last 2 outings it hasnt start up rite away. i would have to use the trollin motor and troll around wit the motor down leveled for about maybe 10 to 15 mins or even more then it would start. any help would be nice... thanks

[Surface Tension]

Could be that when your trailing with motor tilted up the gas in the carbs bowls drain and run into the crank and floods the engine.

Your gas tank is vented so there shouldn't be any negative or positive pressure in your tank.

BUT, if you just filled your tank it is possible that the fuel level inside the tank is above the vent outlet in the top of the tank.

That is a for sure fact if you fill your tank and you have fuel up in the filler hose.

Now if that is the case having your outboard tilted up, the floats in the carb are not level and will allow fuel to be passed freely into the crank and that high fuel level in the tank will travel up the fuel line. Something that will make this problem worse is fuel tanks are underground. That gas is cold and when you pump it into your boats tank and when it starts top warm it will expand. So now your full tank is getting ever fuller.

What can you do.

Don't overfill your tank and take into account that the fuel will expand.

Disconnect the fuel line to outboard when you pull into the dock after a day on the water.

If this should happen again, don't choke and use as much throttle as your controls will allow when starting a flooded engine.

By doing that your opening up the throttle butterfly to allow a larger amount of air to pass.

[jloomis]

thanks Frank! will try what u told me about not choking. before all this started happening i always had it on choked for the first start and it started up rite away just not the last 2 outings. will let u know after tomorrow.