TM 10-3930-671-24 To remove the power piston from its plug, hold the plug in one hand and rap it sharply into the palm of your other hand  (Figure  3.18d).  The  piston  will  slide  out.    Remove the piston ring and seal from the power piston. FIGURE 3.18d. Assemble  Bristol  Socket  Cam  Advance  Screw  Wrench and   Cam   Advance   Screw   Bushing   into   the   advance screw plug hole (Figure 3.18e). FIGURE 3.18e. Loosen   and   remove   the   cam   advance   screw   (Figure 3.18f). FIGURE 3.18f. STEP  19  Return  the  pump  and  holding  fixture  as  a  unit to   its   initial   position   in   the   vise   with   the   rear   of   the hydraulic   head   tilted   slightly   downward.   Remove   the remaining head locking screw and remove the hydraulic head    assembly    by    grasping    with    both    hands    and withdrawing  with  a  slight  rotary  motion  (Figures  3.19a and 3.19b). FIGURE 3.19b. STEP    20    To    disassemble    the    governor,    invert    the hydraulic   head   and   let   the   weights,   governor   thrust sleeve   and   washer   fall   into   your   hand   (Figure   3.20). Place   the   head   and   rotor   assembly   on   top   of   pump holding fixture. FIGURE 3.20. FIGURE 3.19a. F-228