Expert: Everett Peacock - 11/3/2010

Question
QUESTION: This is an ongoing problem that my boat engine mechanic has still not been able to solve. With the engine "cold soaked" (sitting for a week without running)it will start okay but when I go to WOT it will not accell past 3000 RPM. If I leave it at WOT and run the engine for about 10 minutes all of a sudden it kicks in and goes up to 5400 RPM and runs fine the rest of the day, even if I turn it off and restart. I have had the carbs rebuilt, new ignition power pack installed, and the VOR pump removed and a fuel pump only installed. Still the same problem. I am almost sure it is ignition related because when I do the "cold soak" start and let it idle one spark plug lead is not firing and if I take the plug out it is soaked in fuel which tells me it is getting fuel but no spark. Any ideas at all? My engine mechanic and me are ready to use the motor as an anchor!  Thanks.

ANSWER: check the ignition coils.. sounds like you may have one that is bad..

---------- FOLLOW-UP ----------

QUESTION: Is there only one coil? If so, does it provide the spark to both of the plugs at once? Can you give me a brief discription of how this ignition system works? What excatly does the power pak do?

Answer
Here is how the system works... attached in the flywheel are magnets,  they spin around two sets of charge coils.          Stator or charge coils and sensor coils
Charge coils put out from 150 to 250 AC volts at chranking speeds.  The sensor around 5 AC Volts.   
The powerpack collects the the charge coil voltages and holds them.. The sensor coils tell the powerpack which ign coil to send it to.  The Ignition coil takes a small voltage and amplifies it.
The spark plug fires the spark..

This happens for each clyinder that you have.