TM   5-2815-241-34&P FUEL PUMP CALIBRATION - CONTINUED ACTION LOCATION ITEM REMARKS WARNING Fuel is flammable and can explode. To avoid serious injury or death, keep fuel away from open fire and keep extinguisher within easy reach when working with fuel. Smoking is  prohibited  while  working  with  fuel. CAUTION Do not hold throttle in idle position any longer than necessary to complete test. Pump may overheat, since fuel flow is used to cool the pump. NOTE Pump must pick up fuel at 500 rpm without priming. If no fluid pickup is indicated at rotameter,  check  fuel  filter  for  improper  installation  and  motor  switch  for  correct rotation,  Make  sure  open  suction  valve,  hose,  and  gear  pump  connections  are  tight. Check rotameter for air in fuel flow. If air bubbles are present, work pump throttle lever from fuel full open to idle several times, to relieve trapped air in pump. If air bubbling persists, it is an indication of an air leak in the system. Turn test stand off and check the line for loose connections between tank and pump, mating of gear pump housing,  and  full  fuel  supply  tank. If pump is new or has been disassembled or reassembled, run pump slightly over rated speed for 5 minutes to allow bearings and seals to seat, and to purge air from system. 24.  Test  stand  (1) Speed control but- tons  (14  and  15) a. b. Start  test  stand  by  depressing  start button  (18)  until  2130  to  2150  rpm is  indicated  on  test  stand tachometer   (17). Depress  and  release  FAST  (14)  or SLOW  (15)  button  to  maintain  2130  to 2150 rpm. At end of 5-minute period, reduce fuel pump  speed  to  500  rpm. T A     2 4 2 5 6 3 2-339