NOTE At  the  point  where  the  torque  starts  to  rise, the  sleeve  and  tubing  are  Just  touching  the seat.  An additional 1/4 turn produces a seal with  the  fitting  and  restores  the  bow  to  the sleeve. (3) Replace damaged or defective fittings. 6-4. DISASSEMBLY OF M A J 0 R COMPONENTS. Limit  disassembly    of  major  components    to  the  extent necessary   to   repair   or   replace   a   given   assembly   All major components are covered in the following paragraphs.  Refer to Figure 7-1 for major components NOTE Unless otherwise specified, all figures referenced  in  this  section   will   be   found   in Section VII, Illustrated Parts Breakdown. NOTE Remove    tubing    and    hose    assembly    as needed (see Figure 6-1) In the disassembly process.   Tag   tube   or   hose   assembly   for reassembly purposes 6-5. PREPARATION FOR DISASSEMBLY OF SERVICING    UNITS    Position     servicing     unit     at     the maintenance site, set  hand  brakes  and  position  and  set stabilizing jack (17, Figure 7-1) a. Disassembly      Disassemble   the   servicing   unit only   to   the   extent   necessary   to   repair   or   replace   a defective part or parts Do  not  attempt  to  disassemble  any  part  of the  air  pressure  system  without  first  being sure that all pressure has been relieved from the system. (1) Close   gas   cylinder   (10,   11)   valves,   open cam  lever  valves  (2,  Figure  4-1),  shut  off valve   (3),   shut   off   valve   (13)   and   open bleed valve (14) If    gas    cylinders    contain    pressurized    gas when removed,  attach  applicable    warning tags (2) Unscrew  and  remove  flex  hose  assembly from the gas cylinder valve (10, Figure 7-1) If filled pressurized gas cylinders are removed  and  are  to  be  stored,  store  in  a non-hazardous   area,   chained   securely,   or equivalent,     so     they     cannot     fall or be damaged (3) Loosen   tension   on   clamping   band   (9)   by unscrewing    band    handle        and    carefully remove gas cylinders (10) Store cylinders in a safe, clean location. (4) Remove  screws,  washers,  and  nuts   from hinged    top    cover    (1I,    Figure    7-1),    and remove   cover   Remove   screws   and   nuts from  side  panels  (2)  and  remove  panels. Remove   screws,   washers   and   nuts   from left door panel (3) and right door panel (4). Unless  it  is  necessary  to  replace  a  faulty door latch, do not remove the latches (5) Unscrew   and   disengage   tube   assembles (1,   2,   Figure   7-2)   from   the   back   of   the control panel (13, Figure 7-]) (6) Unscrew    and    remove    screws    and    nuts attaching    the    control    panel    (13)    to    the welded    frame    assembly    (19).        Position control   panel   in   a   Jig   or   stand   suitable constructed   to   hold   control   panel   during disassembly procedure. NOTE Note   positioning   of   elbows   In   purification cylinder before cylinder is removed (7) Unscrew   and   remove   nuts,   washers   and screws    attaching    the    tool    box    (6)    and undershield (5) to the welded frame assembly (19) (8) Remove  tubes  (1,  2,  Figure  7-2),  tag   for reassembly purposes Remove nuts, screws,  lock-washers,  and  brackets,  (5,  6, Figure 7-2) from air purification cylinder  (7, Figure 7-1) (See Figure 7-2 for breakdown ) Remove air purification cylinder group from the welded frame assembly (19) (9) Unsnap  and  remove  service  through  (18) from through support.  Do not disassemble service 6-4