Megunticook
New member
Have an '08 Yamaha F4 motor with external Attwood fuel tank (ventless type). Had an issue this weekend with it stalling several times while drawing from the external tank. Each time I switched the fuel cock to the motor's internal tank and was able to restart after a few pulls.
External tank is 6 years old. I cleaned it out thoroughly this year and installed a brand new pickup tube from Attwood. Fuel hoses were replaced last year. Water separator replaced this spring (Yamaha OEM). Primer bulb also replaced (Moeller). Connection fitting on motor was replaced and fuel cock disassembled and cleaned this year.
Yesterday while underway and running off external tank, it stalled so I switched to internal and started troubleshooting. I tried cracking open the cap, squeezing the primer bulb, disconnecting and reconnecting the fuel line on both ends. I noticed the primer bulb did not go hard even with repeated squeezes. I finally got it to harden up at one point and switched back to the external tank, it ran fine for the rest of the day.
I need to understand what happened so I can solve this issue once and for all (should've seen the look my wife gave me when the motor stalled 10 minutes after leaving the dock--we had the kids and 11-mile journey home on mostly open inland bay salt water--22 foot sailboat, dead calm).
Does it sound like an air leak? When we got home I tightened up all the hose clamps on the fuel line. Have ordered a new fuel demand valve also and a new fitting for the fuel line connection at the tank. What else should I be looking at?
Would've been a lousy scene if I hadn't gotten it to draw off the external tank finally. Probably would've ended up trying to empty gas out of the external tank into the onboard tank when that ran out--surely a big mess! Will think about carrying a siphon from now on, or at least a spare fuel can with extra fuel in it.
External tank is 6 years old. I cleaned it out thoroughly this year and installed a brand new pickup tube from Attwood. Fuel hoses were replaced last year. Water separator replaced this spring (Yamaha OEM). Primer bulb also replaced (Moeller). Connection fitting on motor was replaced and fuel cock disassembled and cleaned this year.
Yesterday while underway and running off external tank, it stalled so I switched to internal and started troubleshooting. I tried cracking open the cap, squeezing the primer bulb, disconnecting and reconnecting the fuel line on both ends. I noticed the primer bulb did not go hard even with repeated squeezes. I finally got it to harden up at one point and switched back to the external tank, it ran fine for the rest of the day.
I need to understand what happened so I can solve this issue once and for all (should've seen the look my wife gave me when the motor stalled 10 minutes after leaving the dock--we had the kids and 11-mile journey home on mostly open inland bay salt water--22 foot sailboat, dead calm).
Does it sound like an air leak? When we got home I tightened up all the hose clamps on the fuel line. Have ordered a new fuel demand valve also and a new fitting for the fuel line connection at the tank. What else should I be looking at?
Would've been a lousy scene if I hadn't gotten it to draw off the external tank finally. Probably would've ended up trying to empty gas out of the external tank into the onboard tank when that ran out--surely a big mess! Will think about carrying a siphon from now on, or at least a spare fuel can with extra fuel in it.
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