TM 5-3895-373-34 2.30 REPLACE/REPAIR PROPULSION PUMP - Continued. B. DISASSEMBLE Continued. Do   not   disassemble   servo   piston   unless there   is   visible   damage   to   the   piston   or snap ring/spring seat area. 16. REMOVE SERVO SPRING FROM SERVO PISTON. a. Insert allen wrench into special screw (113). b. Use   a   wrench   and   hold   hex   nut   (114)   from turning. c. Compress  servo  spring  (115)  by  turning  special screw   (113)   clockwise   to   relieve   pressure   on retaining ring (116). Use two flat-blade screwdrivers to compress spring further to allow for removal of retaining ring. Use care when removing snap and retaining  rings.    Snap  and  retaining  rings are  under  spring  tension  and  can  act   as projectiles  when  released  and  could  cause severe eye injury. d. When   servo   spring   is   compressed   enough   to reach inside servo piston (108), remove retaining ring  (116)  from  servo  piston.    Discard  retaining ring. e. Slide servo spring from servo piston. 17. REMOVE PISTON RINGS, PREFORMED PACKINGS, AND BEARING RINGS FROM SERVO PISTON. Use    caution    when    removing    preformed packings and packing retainers.  Scratched or  dented  seal  grooves  can  cause  bypass leakage.      Do   not   use   excessive   force   to remove   preformed   packings   and   packing retainers.      Use   an   o-ring   tool   to   remove preformed packings and packing retainers. a. Use  an  o-ring  tool  to  remove  piston  rings  (117) from Discard servo piston (108).  Discard piston rings. bearing rings. b. Use     an     o-ring     tool     to     remove preformed packings (118) from servo piston. c. Remove  bearing  rings  (119).  from  servo  piston. Discard preformed packings GO TO NEXT PAGE 2-408