TM 5-6115-593-12 TO 35C2-3-463-1 (l) Install  hose  (24)  by  attaching  clamps  (22) and securing to pipe connection (23). (m) Install hose (16) by attaching fittings (15) to reducers (18), then install clamp (13). (n) Install hose (12) by attaching fittings (11) to nipples (10). (o) Install   hose   (8)   by   attaching   to   radiator assembly.  Secure with clamps (3, 4, 6, and 7). Section XVIII.  MAINTENANCE OF FUEL LINES AND FITTINGS 4-50. FUEL   LINES.      The   generator   set   fuel   lines (figure  4-29)  are  hose  assemblies  connecting  the  fuel tank and fuel transfer pump, and the engine. a. Visually inspect all lines and fittings for leakage or deformity,    signs    of    rot    or    physical    damage. Inspect  screen  which  is  welded  inside  filler  neck assembly (47) for tears or damage. b. Replace defective lines and fittings as follows: (1) Remove lines by removing clamps supporting defective hose assemblies to the generator set. (2) Remove spring clamps, or unscrew assembly    from    adapters,    tees,    etc.        as necessary. (3) Separate   defective   lines   or   fittings   from assembly. (4) Install new lines or fittings onto assembly. (5) Install hose assemblies using spring clamps or attaching hardware (fittings). (6) Install   clamps   securing   hose   assembly   to generator set. (7) Recycle fuel if not contaminated in any way. Section XIX.  MAINTENANCE OF ENGINE PREHEAT 4-51. ENGINE    PREHEAT.        The    engine    preheat assembly   (see   figure   4-30)   is   mounted   to   the   base assembly  under  the  forward  end  of  the  engine.    The preheat  system  maintains  the  engine  in  a  preheated, ready-to-start  condition  by  heating  the  coolant  and  oil. This requires an external power source. a. Inspection.    Inspect  thermostatic  switch  S30  (25, figure  4-30),  heaters  H101,  H102,  H103  (18)  and (53 and heater power control contactor K109 (54, figure  4-12)  for  loose  mounting,  loose  electrical connections,  loose  hose  assemblies  and  general signs of overheating.  Inspect hose assemblies for loose connections, leakage, wear or rotting. b. Testing. (1) Thermostatic switch S30 (13,.figure 4-30). (a) Close both shutoff cocks (4). (b) Install a temperature measuring instrument (thermocouple) as close to the thermostatic switch (13) as possible. (c) Switch   on   heater   system.      Observe that    heater    system    automatic-    ally turns off when temperature measuring 4-82