Are you repairing a Skil 1614 or 1616 chainsaw? Is the original fuel filter disintegrated or clogged with old gas? If so, you need this special custom-made reproduction fuel filter. It replaces Skil P/N 180635, that has not been made for years.
Most chainsaws have a small weighted fuel filter that is free to fall to the bottom of the tank so that the saw will run in any orientation. However, the Skil saws use a large fuel filter made of a fine foam which soaks up gasoline like a sponge allowing the engine to be fed a continuous supply of fuel in any orientation. The tank is not shaped correctly to use a weighted filter and so you need to replace the old filter with a new one of the same design.
Installation is easy, but do note that the original plastic hose barb must be reused. For a discussion on fixing these saws and a cross-reference list of other parts you may need, please see my blog post here.