40 HP 4 Stroke EFI Mercury

[rdiekemper]

I am hoping someone can give me an idea of what may be wrong with my outboard. For the past 3 years I have been having issues, only in the summer, with my outboard dyeing off on me. I will run the boat for an extended duration then stop and fish for a while, when I go to restart the outboard it wont stay running, acts like it is getting no fuel. I have tried replacing the gas tank, lines, and filter. After sitting for about a hour or so i can start the outboard and it will run perfectly again. This is a really intermittent thing that doesnt happen every time I am out but it does do it almost every time in summer. Has not quit on me yet in the winter which I do use the boat more during the winter. I have had it at multiple dealers and they can not figure it out either. Any ideas? Thanks for taking the time to read this.

 

[fastjeff]

First of all, when it does this you need to troubleshoot it. Pull a spark plug wire off, affix a spare plug, ground it to the block, and have someone crank it over. Is there spark? If not, that's the problem (overheated electronic component, etc.) If there is spark, it's fuel related (EFI problems, fuel delivery, etc.) But first you have to see which it is!

Jeff