trough  (18)  If  it  is  not  necessary  Unscrew and    remove    nut,    washers    and    screws holding   the   trough   support   to   the   welded frame assembly (19). (10)   Unscrew   and   remove   nuts,   washers   and screws securing the fender assemblies (15) to  the  welded  frame  assembly  (19)  Do  not remove   the   splash   guards   (16)   from   the fender assembles (15) unless it is necessary. (11)   Remove  the  roll  pin  on  the  inside  of   the frame assembly and remove stabilizing jack (17). Use a lifting device of the proper size to remove    the    welded    frame    assembly from the M116A1 trailer chassis. (12)   Unscrew   and   remove   the   nuts,   washers and   screws   attaching   the   welded   frame assembly (19) to the M116A1 trailer chassis.  Using a suitable lifting device (1/2 ton),  lift  welded  frame  assembly  from  the M116A1   Trailer   Chassis   and   position   on suitable work stands (13)   Remove webbing  (20)  from  M116AI  Trailer and  from  the  service  trough  support  (18) only as required for replacement purposes b. Cleaning  Refer  to  paragraph  6-3  a.  for  general cleaning instructions. c. Inspection  Refer to paragraph 6-3.b. for general inspection requirements. (1) Check  all  fittings,  tubing,  and  flex  hose  for cracks, chaffing or damage. (2) Insure that the purifier cylinder Is clean and that  no  odor  or  residue  remains  from  the cleaning process d. Repair  or  Replacement.    Refer  to  paragraph  6- 3.c. for general repair or replacement instructions. (1) Replace  all  damaged  fittings,  tube  or  flex hose assemblies. (2) Repair  or  replace  sheet  metal  components as required. e. Assembly     To     assemble     the     servicing     unit, proceed as follows (see Figure 7-1) (1) If  fabric  (20)  was  removed  from  M116A1 Trailer,  or  from  the  service  trough  support (18), install webbing (20) as required. (2) Using    a    suitable    lifting    device,    lift    the welded  frame  assembly  (19)  and  position the   M116A1   trailer   under   the   frame   and lower the frame into the trailer.  Fasten the frame assembly (19) to the M116A1 Trailer using screws, washers and nuts (3) Insert the stabilizing jack (17) Into its frame recess    and    secure    by    inserting    roll    pin Position and set jack (17). (4) Using  screws,  washers  and  nuts,  position and  secure  fender  assemblies  (15)  to  the welded frame assembly (19). (5) Using  screws,  washers  and  nuts,  position and secure service trough base (18) to the welded frame assembly (19) Position service   troughs   (18)   m   place   and   attach trough to its base. (6) Using   screws,   washers   and   nuts,   attach under shield (5) to  welded  frame  assembly (19)  Using  attaching  screws,  washers  and nuts,  attach  the  tool  box  (6)  to  the  welded frame assembly (19). (7) Using   screws,   washers   and   nuts,   loosely assemble   brackets   (5,   6,   Figure   7-2)   to welded   frame   assembly   (19,   Figure   7-1). Slide  purification  cylinder  (23,  Figure  7-2) into  brackets  (5,  6),  position  cylinder  and tighten  attaching  screws  and  nuts.    Install tubes (1, 2, Figure 7-2) on cylinder (23). (8) Using screws and nuts, position and attach control   panel   (13)   to   the   welded    frame assembly (19).  Attach tubes (1,2, Figure 7- 2)   to   the   rear   of   the   control   panel   (13). (See   Figure   7-4,   Sheet   2   of   2   for   tube attaching points). (9) Using applicable screws, washers and nuts, position   the   right   hand   door   (4)   and   left hand  door  (3)  and  attached  to  the  welded frame  assembly  (19).    Using  screws  and nuts,  attach  the  side  panels  to  the  welded frame assembly.  Using nuts, washers  and screws  attach  the  hinged  top  cover  (1)  to the welded frame assembly (19) 6-5