TM 10-3930-671-24 Main Hydraulic Valve Removal 1. Park  truck  in  a  safe  position  and  fully  lower  the upright. 2. Return  all  controls  to  neutral,  apply  the  parking brake, stop the engine and turn key switch OFF. 3. Be sure there is no hydraulic pressure applied to the system by attachments. 4. Open    the    engine    compartment    and    remove floorboards. 5. Loosen    and    remove    valve    cover    fasteners. Remove valve cover enclosing main valve. 6. Air clean the hydraulic valve and fillings. Refer to illustration, Section 10.0. 7. Loosen  and  remove  all  hydraulic  lines  from  the valve. Note Mark  or  tag  each  line  as  removed  to assure    correct    position    of    line    at assembly. 8. Cap ends of lines to keep them clean.  Tie ends of  lines  to  truck  to  prevent  loose  ends  dropping and leaking oil onto floor. Valve Control Linkage Disassembly Refer to illustration, Section 10.  5. 9. Loosen    and    remove    the    nuts    from    the    two mounting bolts at underside of plate and remove valve lever top plate from the valve. 10. Remove  spring  clip  retainer  and  remove  valve control lever pivot pin. 11. Remove valve control  levers  by  rotating  forward to disengage from valve spools. Note Be  careful  not  to  lose  the  small  pins (30.091) that connect the valve levers to the valve spools. F-461