TM    9-2350-238-10 OPERATION   IN   UNUSUAL   WEATHER– CONTINUED EXTREMELY MOIST HEAT, SAL T AIR, OR SEA SPRAY– CONTINUED 9   Refer   to   page   3-53   for   maintenance   pro- cedures   which   are   required   in   addition   to normal   PMCS   when   vehicle   is   operated in  salt  air,  sea  spray,  or  hot  humid climates. 10   Check   level   of   battery   acid   in   cells   daily, Electrolyte   level   must   not   drop   below   top of   battery   plates.   If   low,   notify   unit maintenance   personnel.   Batteries   self- discharge  at  a  high  rate  when  not  in  use. If  vehicle  is  parked  for  several  days  in hot   climate,   have   unit   maintenance   per- sonnel   remove   batteries   and   store   in   a cool   place,   if   possible. EXTREMELY OR Y HEAT 1   Lubricate   vehicle   at   frequent   intervals   as prescribed   in   appendix   G. 2 3 Operation   of   vehicle   at   high   speed,   on long  hard  pulls  in  lower  gear  ratios  or  in soft   terrain   may   cause   engine   to overheat.   Watch   engine   temperature gauge   and   halt   vehicle   for   a   cooling-off period   whenever   necessary   and   tactical situation   permits.   Do   not   turn   off   engine -   set   hand   throttle   control   lever   to   run engine   at   1,000   to   1,200   rpm   and   allow engine   to   cool. If   engine   temperature   consistently   rises above   200°F   (93°C),   check   filter   bags for   excessive   dust,   and   if   necessary, clean   filter   pats.   Refer   to   page   3-43. When   air   filter   baskets   are   removed,   in- spect   air   separators   for   clogging.   If clogged,   notify   unit   maintenance personnel. 4   Do   not   park   vehicle   in   sun   for   long periods   of   time.   If   no   suitable   shelter   is available,   cover   vehicle   with   tarpaulin. Tarpaulin   should   be   suspended   above cab   surface   to   allow   air   ventilation,   if possible. 5 6 7 8 Keep   all   doors   and   cupola   covers   open whenever   possible   to   aid   ventilation   of vehicle. Clean   and   lubricate   exposed   metal   sur- faces   and   gun   bore   of   machine   gun   fre- quently.   When   machine   gun   is   not   in use,   cover   surfaces   with   a   film   of   PL special   or   CLP   and   keep   cover   in   place. Refer   to   page   3-57   for   maintenance   pro- cedures   which   are   required  in   addition   to normal   PMCS   when   vehicle   is   operated in   desert   climates. Check   level   of   battery   acid   in   cells   daily. Electrolyte   level   must   not   drop   below   top of   battery   plates.   If   low,   notify   unit maintenance   personnel.   Batteries   self- discharge   at   a   high   rate   when   not   in   use. If  vehicle  is  parked  for  several  days  in hot   climate,   have   unit   maintenance   per- sonnel   remove   batteries   and   store   in   a cool   place,   if   possible. TOXIC GAS, EXTREME DUST, SAND  STORMS 1 2 OR DUST AND Carbon   monoxide   is   a   poisonous gas  and  can  cause  personal  in- jury   and   possible   death.   The gas-particulate   filter   unit   will not   protect   against   carbon monoxide.   If   you   have   symp- toms   of   carbon   monoxide poisoning,   seek   immediate medical   help.   Keep   area   ade- quately    ventilated. In   event   of   a   chemical   attack   or   when operating   vehicle   under   extremely   dusty conditions,   driver   and   crew   should   use gas-particulate   filter   unit.   Refer   to   TM 3-4240-280-10   for   operation   of   gas- particulate   unit. When   operating   in   extreme   dust   or   dur- ing  a  dust  or  sand  storm,  keep  all  doors and   cupola   covers   closed   and   locked when   not   in   use. Change   3 2 - 1 09