This will be my first time to start a motor using a hose & muffs. It's a 2008 9.9 Mercury. I bought new muffs a long time ago for a 2001 Evinrude 9.9, but never used them. Will they work with the Merc? How can I tell if they are working properly? Anything else I should know? I want to make sure the motor is running before I take boat to the ramp and launch for the summer.