no idea what the plug gap should be, probably just straight out the box would do. high rpm on starting: adjust idle screw to let less fuel in. hard to restart after dying on low sounds like slight flooding. you may need to adjust the throttle screw to let less fuel in, and if it has a float carb (one with a bowl) raise the float a bit. there should be a screw under the bowl to lift it up.
steve
May 2005