TM 5-6115-590-12 Section XII.  Maintenance of Compressed Air and Vacuum System 4-48.  General The    compressed    air    and    vacuum    system    provides compressed  air  and  vacuum  for  external  applications and  compressed  air  for  scavening  the  engine  air  inlet filter  and  for  heating  the  water  storage  compartment. These systems consist of control valves, tube and hose assemblies, vacuum ejector and exhaust ducts. 4-49.  Tube Assemblies and Plumbing Fittings a.  Compressed Air System. (1)          General.          The     hose     and     tube assemblies and plumbing fittings provide interconnection of the compressed air system. (2)      Removal.      Remove   hose   and   tube assemblies    and    plumbing    fittings    as    required    for replacement  following  the  sequence  of  index  numbers on fig.  4-30. (3)  Cleaning, Inspection and Repair. (a)    Clean  hose  and  tube  assemblies and plumbing fittings with an approved cleaning solvent and dry thoroughly with filtered compressed air. (b)      Inspect   all   threaded   parts   for stripped,   crossed   or   peened   threads.      If   threads   are damaged beyond repair, replace the damaged part. (c)        Inspect    hose    assemblies    for cracks,.  breaks, chafing and damage to hose interior.  If damaged, replace hose assembly. (d)  Inspect tube assemblies for kinks, bends, cracks, or other damage which might restrict flow or  result  in  leakage.    Inspect  nuts  and  sleeves  on  tube assemblies  for  loose  sleeves  or  damage  to  nuts.    If damaged, replace tube assemblies. (e)        Inspect    plumbing    fittings    for cracks  or  clogged  passages.    Clean  clogged  passages and replace cracked fittings. (f)    Replace  all  gaskets  and  packings if removed regardless of condition. (4)       Installation.      Install   hose   and   tube assemblies   and   plumbing   fittings   in   reverse   order   of removal   procedures   and   sequence   of   index   numbers assigned to figure 4-30. b.  Vacuum System. (1)      General. The hose and tube assemblies and plumbing fittings provide interconnection of vacuum system components. (2)      Removal.      Remove   hose   and   tube assemblies   and   plumbing   fittings   as   required   in   the sequence of index numbers assigned to figure 4-31. (3)  Cleaning, Inspection and Repair. (a)    Clean  hose  and  tube  assemblies and    plumbing    fittings    using    an    approved    cleaning solvent and dry thoroughly with filtered compressed air. (b)      Inspect   all   threaded   parts   for stripped,   crossed   or   peened   threads.      If   threads   are damaged beyond repair, replace the damaged part. (c)        Inspect    hose    assemblies    for cracks, breaks, chafing and damage to hose interior.  If damaged, replace hose assembly. (d)  Inspect tube assemblies for kinks, bends, cracks or other damage which might restrict flow or  result  in  leakage.    Inspect  nuts  and  sleeves  on  tube assemblies   for   loose   sleeves   or   damaged   nuts.      If damaged, replace tube assemblies. (e)        Inspect    plumbing    fittings    for cracks  or  clogged  passages.    Clean  clogged  passages and replace cracked or damaged fittings. (f)    Replace  all  gaskets  and  packings if removed regardless of condition. (4)       Installation.      Install   hose   and   tube assemblies   and   plumbing   fittings   in   reverse   order   of removal   procedures   and   sequence   of   index   numbers assigned to figure 4-31. 4-50.          Compressed     Air     and     Vacuum     System Components a.  Removal.  Disconnect plumbing connections to each    component    as    required.        Remove    attaching hardware    and    remove    component    to    be    replaced following  the  sequence  of  index  numbers  assigned  to figure 4-30 and 4-31. b.  Cleaning, Inspection and Repair (1)      Clean   components   with   an   approved cleaning     solvent     and     dry     thoroughly     with     filtered compressed air. (2)      Inspect   threaded   areas   for   crossed, stripped,  or  peened  threads.    If  threads  are  damaged beyond  repair,  replace  components  in  reverse  order  of removal. Section XIII.  Maintenance of Engine and Skid Assembly 4-51.  General The engine and skid assembly contains the gas turbine engine, the upper and lower electrical power chassis, oil and fuel tanks, fuel boost pump, fuel filter and fuel float tank.      Access   to   the   engine   and   skid   assembly   for replacement of components is obtained by removing the access    panels    as    shown    in    figure    4-32.        Before removing    the    access    panel    to    the    fuel    and    oil components,    the    electrical    connectors    to    the    main instrument panel must be disconnected. 4-75