Use carb cleaner or better yet, if you have access to one, a parts washer tank. Using gas or kerosene can be very dangerous, never mind the cost. Finding shavings in the housing conserns me, that sounds like the mesh element part is disintigrating. I've seen them do that, especially on one that's been sitting and not kept oiled. They actually rust apart. Had the original rocker cover breather do that on mine. If that's the case, you might look into converting the housing to take a dry element or K&N filter.
