TM 10-3930-664-24 2-74.  FUEL LEVEL SENDING UNIT REPLACEMENT This task covers: Removal, Cleaning, Inspection, and Installation INITIAL SETUP: Tools and Test Equipment: Equipment Condition: General Mechanics Tool Kit (1, App.  E) Batteries disconnected (para.  2-78) Materials / Parts: Gasket, Item 5 (1 ea.) A.  REMOVAL WARNING Fuel   is   very   flammable   and   can   easily   explode.      To   avoid   serious   injury   or   death,   observe   the   following precautions: - Keep fuel away from open flame or any spark (ignition source). - Keep at least a B-C fire extinguisher within easy reach when working with fuel. - Do not work on fuel system when engine is hot; fuel can be ignited by a hot engine. - Post signs that read "NO SMOKING WITHIN 50 FEET" when working with open fuel or fuel tank. WARNING Electrical   shock   hazard.      Disconnect   battery   ground   cable   or   power   source   prior   to   working   on   electrical components.  Failure to heed warning could cause shock, injury or death.  If electrical shock occurs, administer first aid and seek medical assistance immediately. 2-216