Chamois leather commonly known as a “Shammy” is a type of porous leather that has almost no abrasive properties, and can be used as a absorbent drying material for almost any surface.
Now I am talking about a real shammy made of chamois leather not one of the new synthetic imitation. The shammy has several uses, it can be used to collect water or collect dew in a survival situation. Just wipe the wet areas and squeeze the water out into a container. It also can make a good towel, because of the amount of liquid it will absorb. But probably the best use of a shammy is to filter fuels.
Shammies are good expedient fuel/water separators. They have been used by pilots and boaters for many years to filter water out of gasoline. When a shammy is soaked with clean gasoline, it will not allow water to pass through its surface fibers. Take a large funnel and drape the shammy inside it to form a bowl. Pour the gasoline through the gasoline soaked shammy. Stop when you start to see water accumulating, remove the shammy from the funnel being careful to keep the gasoline and water separate. Dump the water and start over, continue until the gasoline is all filtered. If you don’t have clean gasoline, remember that gasoline floats on water, so the water will settle to the bottom. Soak your shammy in the top portion of the gasoline.
Shammies that are soaked in water will pass water, so do not use a water soaked shammy for filtering fuel, however they can be used for filtering sediment out of water.
If you have to use old fuel from unknown sources, I would recommend filtering it with a shammy prior to using it. A shammy will also work for filtering the water out of kerosene. I believe that it will also work to filter water out of diesel, although I have not been able to verify this.