My guess is that your battery is about to fail or you have something draining the battery while the boat is unused. Your alternator has not had a chance to re-charge the battery in the first 15 minutes and a big load like a trim motor is dragging the voltage down enough to affect the fuel injection or ignition.
Check your battery voltage with an accurate volt meter connected directly to the battery terminals before you start the boat and with all loads off, the next time the boat has sat for 12 hours. If the battery has less than 12.4 volts, something is drawing the battery down or the battery is failing.
|