8. Refer  to  Page  PM13,  install  the  Air  Operated  PTO Shift   as   follows:      Oil   o-rings   (Item   3),   install   on adaptor (Item 50).  Place adaptor over shift shaft and into   the   PTO   housing   with   the   counterbored   end outboard.    Place  o-ring  (Item  11)  carefully  over  the end of the shift shaft.  Position spring (Item 51) over the shift shaft and into the adaptor (Item 50).  Place bump  ring  (Item  13)  over  spring  (Item  51).    Move shift collar and restrain to make shift shaft project as far as possible.  Install piston (Item 9), washer (Item 7) and nut (Item 6).  Tighten nut to specified torque. Install  felt  ring  (Item  10)  (after  soaking  in  transfer case  lubricant)  in  wide  groove  of  piston.    Oil  o-ring (Item  8)  and  install  in  the  outboard  groove  of  the piston.    Install  cylinder  cap.    Slip  the  shift  cylinder tube (Item 43) (31/8" long) over the piston, onto  the adapter.    Fit  the  shift  cylinder  cap  into  place  and install the four capscrews that retain the assembly to the PTO unit, tighten to the specified torque. Fig.  38 9. Install  the  indicator  light  switch  (Item  20)  with  same washers (Item 21) as were removed during disassembly.          Check     switch     operation     with     a continuity tester (and air pressure applied to the shift cylinder, if so equipped). 10.  Install   the   blanking   sleeve   (Item   70)   on   the   PTO output to seal the output shaft section of the PTO, if a yoke is not to be installed immediately. 11.  The  PTO  unit  includes  an  oil  pump  that  consists  of items 73 through item 80 on Page PM12.  Also refer to  Fig.    39.    The  piston  (Item  73)  is  driven  by  the eccentric  section  of  shaft  (Item  65).    A  check  valve (Item  74)  is  retained  within  the  piston  by  a  spring type retaining ring (Item 75).  This check valve must be  installed  with  the  free  flow  direction  and  arrow direction pointing toward the PTO shaft.  This allows a small portion of the oil pump output to be directed onto  the  shaft’s  eccentric  surface.    Screw  nut  (Item 77) onto cylinder (Item 79) with nylon portion pointing away from the hexagon section of the cylinder.  Coat the piston, check valve and retaining ring  assembly  with  transfer  case  lubricant.    Put  the spring  (Item  76)  into  the  counterbore  of  the  piston and then put the cylinder over the spring and piston. Push the piston into the cylinder until the end of the cylinder  is  just  even  with  the  port  in  the  side  of  the cylinder.      The   piston   should   move   freely   without binding.    Screw  the  cylinder  into  the  PTO  bearing carrier (See Fig.  39).  Rotate the PTO shaft to place the high point of  the  cam  under  the  piston,  screw  the  cylinder  in until  the  outer  end  of  piston  is  visible  short  of  the cylinder side port.  Rotate the PTO shaft to verify that it is indeed on the high point of the cam.  Screw the cylinder  in  until  the  outer  end  of  the  piston  is  just even with the side port; unscrew cylinder at least one turn,   but   not   more   than   one   and   one   half   turns; tighten lock nut against the PTO bearing carrier with one side port of the cylinder pointing in the direction shown  on  Page  PM15.    Use  pipe  dope  on  all  pipe threaded fittings.  Screw check valves (Item 80) into place  in  the  cylinder.    The  inlet  check  valve  should be  installed  (with  the  arrow  pointing  into  cylinder)  in the end of the cylinder.  The outlet valve should have the arrow pointing away from the cylinder and should be in the position shown on Page PM15 to allow the hose  (Item  4)  to  be  used  to  connect  the  pump  to fitting (Item 5) at the front of the case. 8. Refer to section VI G, paragraph 12 for installation of the PTO unit on the transfer case.  Also See Fig.  33 and Fig.  37. 9. Refer   to   Page   2   and   Page   PM15   for   the   proper installation  of  the  oil  lines.    Also  see  Fig.    1,  2,  and 38. 10.  Check   oil   flow   out   of   oil   pump   upon   installation. Refer to Section III B of this manual. Fig. 39 -27-