Dies at WOT starts up fine.

[FireAm94]

I went to WOT finally and it ran good and before it came close to topping out (4 or 5 seconds WOT at most) it died...no dieseling or anything....just died. The primer bulb was very soft and I primed her and she started right up. I searched and found some that described primer bulb problems but I believe they had idle problems too. This is a Yamaha 40ESK. Does it sound like an air leak between the tank and motor?<br /><br />Thanx<br />Joe

 

[jim dozier]

Re: Dies at WOT starts up fine.

You are describing running out of fuel. You have either a problem with:<br /><br />1. the tank vent is clogged or closed.<br />2. the fuelpickup in the tank is clogged or sucking air.<br />3. the fuel line including fuel bulb is clogged or sucking air.<br />4. the fuel pump isn't working.<br />5. the carb main jet is clogged.<br /><br />Check them in order. Have you recently installed a new fuel bulb. They are 1-way and can be put in backwards, also some of the aftermarket quality control is suspect.<br /><br />Try pumping the fuel bulb when the engine starts to die. If it picks up, suspect the fuel pump.<br />After checking 1-4, you can choke the engine which will check for a lean carb. You can disconnect the fuel line at the engine connector and you should be able to pump fuel into a container with the fuel bulb.

 

[FireAm94]

Re: Dies at WOT starts up fine.

Thanx for the checklist! I'll start with the troubleshooting now...replaced the fuel pump about 2 months ago so I hope it's an air leak.<br /><br />Thanx again!<br />Joe