1987 Mercury 115 HP ELPTO Model 1115727. Motor has developed an intermittent miss at idle speed that leads to the engine quitting. I need to keep the idle speed at 1,000 RPM to keep it running but the miss is very pronounced when it happens. Carbs have been rebuilt and tuned. Plugs (BUHW-2) changed. Fuel filter changed. Some of the plugs appear to run a bit hotter than other from looking at the black burn pattern. I'm wondering if I have a weak coil that is not consistent with power.
