I recently, 4 days ago, bought an 1882 Westy with a 1978 engine in it.  The engine runs well, except for minor push rod tube leaking.  However the heat is sub-optimal for an air cooled engine.  The heat coming from the defrost vents is warm yet not hot.  This engine doesn't have the rear blower in front of the alternator like those found on the 82 engine.  Could this be the cause of lack luster heat?