115 Merc dies in rough water

[bob123]

Hi All,

I just bought a 95 17' Fisher with a 2002 115 hp Mercury EFI. In rough water as we go over a wake and land moderately hard, the engine stops. It doesn't sputter or cough, it just quietly dies. Luckily, it starts right up again. I had the engine checked out before I bought the boat and they said everything was fine. I'm new to boating so this is a little spooky. Thanks for any ideas.

Bob

 

[airframer]

Re: 115 Merc dies in rough water

how does your battery connections look? if they just shake a little it might be enough to kill it.

 

[j_martin]

Re: 115 Merc dies in rough water

If it twer mine, I'd set it up on the cuffs, idle it, and poke around, pushing and pulling on wires, especially battery connections and also wires near the ignition. Could be something as simple as a kill switch wire laying over a ground point and rubbed thin.

hope it helps
John

 

[big_b16]

Re: 115 Merc dies in rough water

Be careful pulling on wires while standing in water from the muffs, might be self-critiquing.

 

[j_martin]

Re: 115 Merc dies in rough water

Be careful pulling on wires while standing in water from the muffs, might be self-critiquing.

Secondary (spark plug) wires wouldn't kill more than one cylinder. Stay away from them. Forgot to mention that. They bite.

LOL
John

 

[bob123]

Re: 115 Merc dies in rough water

Thanks Guys,

There's a lanyard kill switch on the throttle, maybe its tripping when the boat gets jarred. Do these kill switches typically tie into the ignition switch or do they operate by some other means?

Thanks

Bob

 

[j_martin]

Re: 115 Merc dies in rough water

Thanks Guys,

There's a lanyard kill switch on the throttle, maybe its tripping when the boat gets jarred. Do these kill switches typically tie into the ignition switch or do they operate by some other means?

Thanks

Bob

The "ignition" switch and the kill switch both stop the motor by grounding a wire to the switch boxes. It's black with a yellow tracer. By the way, there may be a mercury "tilt" switch that is hooked into that same circuit, that prevents the engine from firing if it's tilted out of the water. Could be loose, or you're getting so violent it shorts out anyway.

hope it helps
John

 

[bull island dave]

Re: 115 Merc dies in rough water

Might want to check the condition of the gas tank. If there is rust and muck in the bottom of the tank the rough water might just stir it up enough to clog the fuel line. Just a thought.

Dave

 

[Bigjohn1]

Re: 115 Merc dies in rough water

Loose battery connections will not cause this engine to die, look elsewhere.