What would cause oil to blow out of air cleaner on a 2000 harley-davidson sportster?
You need to follow up on your answer, Mr Flatech, This engine breathes through the heads instead of the lower crankcase. The crankcase pressure that exists the heads is full of oil mist. This mist is supposed to be Pulled into the Carb and burned as part of your air fuel mixture. Sometimes oil builds up in the air cleaner and blows back on the oil tank. One more thing, Sometimes if your bike sits for a week or two oil will leak past the oil pump and build up in the bottom end of the engine. When you start the engine the oil pump can’t keep up and the excess oil is pushed through the crankcase vents. The crankcase vents into the air cleaner creating extensive oil blow back. Some sportsters are worse than others, It is really just, THE NATURE OF THE BEAST.
