TM 10-3930-669-20 4-10.  FUEL/WATER SEPARATOR REPLACEMENT/REPAIR  (CONT). a. Removal. WARNING Fuel is very flammable and can explode easily.  To avoid serious injury or death, keep fuel away from open fire and keep fire extinguisher within easy reach when working with fuel.  Do not work on fuel system when engine is hot.  Fuel can be ignited by hot engine.  When working with fuel, post signs that read NO SMOKING WITHIN 50 FEET (15 m). (1) Position wiping rags under fuel/water separator (1) to catch excess fuel. 4-28