Recent AA-1B annual parts: The small gray round things are the remains of carburetor heat valve bushings that were coming apart allowing heated unfiltered air into the engine at all times. 37 year old Black fire sleeved fuel lines, Bent and broken aileron stops, broken fuel cap scupper, hole worn into the oil separator, cross threaded drain tube fitting, Spot face on intake tube retainers was too deep, not allowing the gasket to contact the tube flange.