Re: 73 johnson
It should slide into a grommet at the top. This lets the water through your engine to cool it. Have you checked for spark when it doesn't start? DWJ was alluding to that. When you are in the water you have back pressure that you don't have on muffs. Check your spark and make sure that it is bright blue and snaps on all cylinders. If you have one that is yellow swap the ignition coil to another cylinder and see if the weak spark follows.
