TM10-3930-660-10 PREVENTIVE   MAINTENANCE   CHECKS   AND   SERVICES B  -  Before D  -  During A  -  After Item No. 3 4 2-18 Interval D A w Item  To  Be  Inspected Procedure:  Check  for  and  repair, fill  or  adjust  as  necessary HYDRAULIC   TANK/RESERVOIR With  all  cylinders  retracted,  check  oil level  in  tank.  Oil  level  should  be risible  in  the  upper  sight  glass.  Refer to  LO1  0-3930-660-12. RADIATOR Cooling   system   is   pressurized. Remove  radiator  cap  slowly  and  only when  engine  is  cool  or  painful  burns could   result. NOTE Use  coolant  overflow  bottle  to  fill  or check  coolant  level.  If  coolant  is  not visible  in  overflow  bottle,  the  system must  be  refilled  through  the  radiator cap. a. b. Check  the  coolant  level  in  the overflow  bottle.  Maintain  level approximately  1/3  full  to  2/3  full (2      qts.). Visually   check   radiator   for damage   or   obstruction. Remove   any   obstruction. W  -  Weekly Equipment   Is   Not   Ready/ Available   If: Radiator   is   leaking.