Just over the last couple of weeks I have taken the boat out either to pull the kids sking or Trolling. After about 2 hours of running and then taking a break for 1 hour I went back to start the boat and it started fine but when I went to put it in gear it bogged down and stalls. This has happened 3 times over the past 2 weeks. It will run ok but after working it for a while and then letting it sit it will stall when put into gear. I have changed the plugs and also the fuel filter. Any ideas THANKS in advanced.