Recently took boat out and ran it for about 20 mins. It ran fine. Shut it down and fished for about an hour or so. It started up fine but as soonas it planed out the motor shut off. There was no sound of any type. Tried to restart it but the motor wouldn't turn over. Turned it and it spun freely by hand. It took alittle over an hour to get to nearest boat ramp and get it loaded and then it fired right up?!!! Any ideas on where to start I am new to the boat motors.