SERVICE MANUAL Fig. 4 8. Position hose socket in swivel nut and reassemble   pipe   adapter   (if   removed)   to   lock swivel  nut  on  the  fitting.  Thread  the  fitting  and swivel  nut  (with  pipe  adapter)  assembly  into  the hose  as  shown  in  Fig.  5  leaving  .793-1.59  mm (1/32  Inch  to  1/16  inch)  clearance  between  nut and socket so that the nut can swivel freely. Fig. 5 9. Repeat  steps  5,  6,  7  and  8  on  opposite  end  of hose to install the remaining nut and fitting. 10. Lubricate   the   threads   of   the   hose   assembly when  connecting  the  lines  (use  light  engine  oil sparingly). 11. When  installing  the  new  hose  assembly  on  the vehicle  be  sure  to  check  for  possible  leakage and correct any leaks if leaks are present. HOSE ASSEMBLY SPECIAL INSTRUCTIONS Installation   and   routing   of   these   hoses   is   just   as important as special attention given to the installation  of the ends. Common problems encountered with installation  and  routing  which  will  result  in  short  service life of these hoses are: 1. High external temperatures will shorten the life of a  hose.  Route  hoses  away  from  hot  manifolds and exhaust systems. 2. Abrasion  of  hoses  will  cause  outer  surfaces  to wear   and   weaken   the   hose.   When   installing these flexible hoses avoid contact or crisscrossing,   sharp   surfaces   and   contact   of moving   parts   (shift   levers   and   pedals).      Clip hoses   in   place   to   prevent   vibration,   abrasion; route   hoses   together   and   parallel   If   the   hose cannot be clipped adequately, the hose must be equipped with a protective conduit (cover).  If the hose being replaced has a protective conduit, be sure to use a cover on new hose. 3. Flexing  of  short  hoses  should  not  be  allowed, since   this   will   tend   to   wear   the   hoses   at   the fittings. If the hose must move, do not permit the hose  to  twist;  keep  the  bend  in  the  hose  in  the same plane as the movement where the hose is connected.  Provide  enough  hose  to  permit  any movement  which  may  be  required.  Avoid  sharp bends or turns in the hoses, NYLON TUBING In past years nylon tubing of varying construction has been used in such diverse applications as rear axle shift control    lines,    windshield    wiper    motor    supply    lines, transmission   shift   control   lines   and   engine   governor control lines. With production of nylon tubing as a replacement for certain    copper    tubing    in    chassis    air    brake    system applications, a superior nylon tubing which is suitable for all of the above applications as well as air brake system applications is now being provided for field service use. NYLON TUBING ASSEMBLY INSTRUCTIONS For the most part nylon tubing in air brake systems is assembled much like copper tubing.  The same fittings, sleeves and nuts used with copper tubing can be used with nylon tubing.  Long or short tube nuts may be found on chassis in service with nylon tubing (Fig. 6). Either nut may be satisfactorily used on’ the nylon lines. If  copper  tubing  is  being   substituted   for   nylon tubing,   the   short   tube   nut   must   not   be   used. Either the short tube nut or the long tube nut may be used satisfactorily with nylon tubing. A    tube    support    or    insert    will    be    used    in    all applications of the nylon tubing in air brake systems. The insert  provides  a  stiff  or  rigid  area  for  the  sleeve  to  be crimped   or   compressed   on   the   tubing   and   prevents collapsing the tubing when the nut is tightened. The parts listing notes that there are some sizes of tubing that are used   only   in   accessory   piping   systems.      In   repairing accessory piping systems tube sup- CTS-4079 - CHAPTER XII - Page 4