It sounds like the float level may be set too high. The engine takes all the extra fuel when it is running at speed but the level of fuel in the float bolw rises at idle, when the engine does not use as much. If the float level is too high, it will or could allow fuel to spill over and cause the strong fuel smell. Over time it can also put too much fuel into the engine at idle and if there is too much fuel, it can wash the oil off the rings, causing excessive wear at start-up.
