For an '02 Merc 150 carbed Saltwater, how long should the warning horn sound when the ignition is turned on? Mine sounds once for about half a second unlike my old 1985 150 which would give one beep followed by a pause and then three shorter beeps. I imagine this is correct but just want to be sure since this is my first new outboard.<br /><br />Thanks.<br /><br />Brian