TM 55-2840-241-23 (a)  Idle  speed.  (Refer  to  paragraph  5-12e.) Do   not   allow   sand   or   dirt   contamination on  the  fuel  control  drive  splines  during installation. (1)  If  a  new  fuel  control  is  to  be  installed,  trans- fer   the   tube   fittings   from   the   removed   control   to   the new   control.   Use   new   preformed   packing.   Lubricate preformed  packing  on  fuel  tube  fittings  with  oil  (item 8,  table  2-2).  Do  not  lubricate  preformed  packing  on  air tube fittings. Tighten the unions to 75-110 in. lb. Do not tighten   jam   nuts. (2)  Check  the  max  flow  stop  setting  and  adjust if  required.  (Refer  to  paragraph  5-12h.) (3)   Coat   the   fuel   control   drive   shaft   splines with  lubricant  (item  14,  table  2-2),  the  studs  with  anti- seize  compound  (item  15,  table  2-2  ),  and  fuel  tube  fit- tings  with  oil  (item  8,  table  2-2). (4)  Install  the  fuel  control  on  the  mounting  pad studs.   Make   certain   the   fuel   control   drive   splines   are properly  engaged  in  the  gearbox  drive  splines;  the  fuel control   must   be   flush   against   the   gearbox   mounting pad.  Secure  the  control  with  three  washers  (43,  figure 5-3)   and   self-locking   nuts   (42).   Tighten   the   nuts   to 70-85 in. lb. (5)   Install   air   tube   (9,   figure   5-2)   between   the fuel   control   and   governor.   Tighten   coupling   nuts   to 80-120 in. lb. (6)  Install  air  tube  (15)  between  the  control  and accumulator.   Tighten   coupling   nuts   to   80-120   in.   lb. Tighten  the  jam  nut  on  the  tube  fitting  to  55-80  in.  lb. (7)  Install  air  tube  (7)  between  the  control  and governor.   Tighten   coupling   nuts   to   80-120   in.   lb. Tighten  the  jam  nut  on  the  tube  fitting  to  55-80  in.  lb. (8)   Install   fuel   tube   (16)   between   the   control and  fireshield.  Tighten  coupling  nuts  to  80-120  in.  lb, (9)  Install  air  tube  (5)  between  the  control  and governor.  Tighten  coupling  nuts  to  80-120  in.  lb. (10)  Install  fuel  tubes  (3  and  4)  between  the  fuel pump  and  control.  Tighten  coupling  nuts  to  150-200  in. l b . (11)  Assemble  the  lever  on  the  control  and  secure with  a  self-locking  nut.  Position  the  lever  in  accordance with   the   Rigging   Check.   (Refer   to   paragraphs   5-12d.) Tighten   the   nut   to   40-50   in.   lb.   (Overtorquing   causes binding  of  the  lever  shaft.) (12)  Check  the  pneumatic  tubes  for  leaks.  (Refer to   paragraph   5-8.) (13)   Bleed   the   fuel   system.   (Refer   to   paragraph 5-7.) (14)   Test   the   engine   as   outlined   in   Chapter   10 and   make   the   following   adjustments   if   required. (b)   Start   derichment.   (Refer   to   paragraph 5-12g.) (c)  Start  acceleration  -  AVIM.  (Refer  to  para- graph  5-12g.) (15)  Make  appropriate  entry  relative  to  fuel  con- trol   replacement   in   the   engine   log. d.   Rigging   Check. Do   not   adjust   the  minimum   stop   to   com- pensate   for   aircraft   rigging   difficulties. The   minimum   stop   is   set   on   a   flow   bench and   is   not   a   field   adjustment. N O T E For   N1   rigging   procedures,   refer   to   TM 55-1520-228-23. Check   the   rigging   of   the   gas   producer   fuel   control after   a   deceleration   check   has   revealed   the   decelera- tion  time  to  be  less  than  the  allowable  minimum.  This check  is  also  required  after  installation  of  a  fuel  control or   any   component   of   the   rigging   system.   Make   the rigging   check   with   the   engine   shut   down   using   the following   procedure. (1)  Check  to  ensure  that  sufficient  travel  is  pro- vided   to   allow   physical   contact   with   the   gas   producer minimum stop at or before the full closed position of the twist   grip. (2)  Check  the  travel  to  the  opposite  end.  Phys- ical  contact  must  be  made  with  the  gas  producer  max- imum   stop   at   or   before   the   full   open   position   of   the twist   grip. (3)   Looseness   encountered   in   the   rigging   must be   minimized   by   replacement   of   worn   items   and/or accuracy   of   the   rigging.   Looseness   that   cannot   be removed   must   be   within   the   limits   indicated   in   figure 5-5.  Check  the  looseness  as  follows: (a)  Start  with  the  twist  grip  at  the  full  open position  then  rotate  the  grip  to  the  IDLE  position.  The pointer   must   beat   the   30   degree   mark. N O T E The pointer must be exactly at the 30 degree mark for initial rigging setup or when rigging is being adjusted. (b)  Start  with  the  twist  grip  at  the  full  closed position  then  rotate  the  grip  to  the  IDLE  position.  The pointer   must   be   no   more   than   5/64   in.   below   the   30 degree    mark. Change 23        5-9