TM    9-6115-668-13 Table  2-4  Operator  Preventive  Maintenance  Checks  and  Services-continued. Item No. 23 24 25 26 27 28 29 30 31 32 Interval Before Before Before Before Before Before Before Before Before Before Location Item to Check/Service ENGINE   COMPARTMENT- continued Battery charging alternator V belts Flame Glowplug System Heating unit and heat exchanger Air hoses Air hose Air pipe inlet Gas exhaust manifold Gas  exhaust  intermediate pipe Fuel pipes Procedure Check battery charging alternator for loose, damaged, or missing parts. Inspect V belts for cracks, fraying and looseness. Check that fuel line and cables are firmly attached to both flame glow- plugs. Check that heating unit and heat ex- changer box are firmly attached to mounting plate; and check for loose, missing, or damaged hardware. Check that air hoses between heating unit and heat exchanger box, and be- tween heat exchanger box and diesel engine are firmly attached and un- damaged. Check that air hose above oil hose is firmly attached to heat exchanger housing and undamaged. Check that air pipe inlet is firmly at- tached to heating unit, and points to- ward the terminal box. Check that gas exhaust manifold is firmly attached to heating unit, and is properly connected and aligned with gas exhaust intermediate pipe. Check that gas exhaust intermediate pipe is firmly attached to base frame. Check that both fuel pipes are firmly attached to heating unit with no leaks. Not Fully Mission Capable  if: Loose,   damaged,   or missing   parts. V  belt(s)  is  (are) frayed  or  broken. Any  fuel  leak,  loose, damaged,   or   missing fuel  lines. If box is loose or any damaged,   loose   or missing    hardware. Air hoses are loose or damaged. Air hoses are loose or damaged. Air pipe inlet points in the other direction. Gas exhaust manifold is not connected to gas exhaust inter- mediate   pipe. Gas exhaust inter- mediate pipe is loose. Fuel pipes loose or damaged.   Any   fuel leak. 2 - 2 5