TM 5-3895-382-24 2. Put the multimeter leads on terminals "A" and "B". The  resistance  should  be  between  30  and  34  ohms  If the resistance is not correct, replace the start relay. 3. If the resistance is correct, disconnect terminals "4" "7", "6" and "9". 4. Put   the   leads   of   the    8S-4627   Test   Light   between terminals "4" and "7".  The test light should not turn on. Put the leads of the test light on terminals "6" and "9". The test light should not turn on. If the test light turns on, the start relay must be replaced. 5. If the start relay is not defective, refer to Troubleshooting for other tests of the starting system. Charging System The  condition  of  the  charge  in  the  battery  at  each  regular inspection    will    indicate    if    the    charging    system    operates correctly.  A problem exists when the battery is constantly in a condition  of  low  charge.    A  problem  also  exists  if  more  than one  ounce  of  water  must  be  added  to  a  cell  in  the  battery during the following periods: One week Each 100 hours of operation Testing the charging system is preferable when the following conditions exist: The alternator is mounted on the engine. The voltage regulator is mounted on the engine. The wiring and electrical components which are used in the test are a permanent par of the electrical system. Bench testing can be done on the alternator and the voltage regulator.        This    testing    will    determine    if    the    individual component is defective. When   a   component   is   replaced   or   repaired,   the   charging system should be tested.  This test will verify that the charging system is operating correctly. Refer to Specifications, "Alternator and Regulator for additional information. Before   the   charging   system   is   tested   on   the   engine,   the charging system and the battery must be inspected.  Use the following inspection procedures: 1. The  battery  must  be  charged  to  at  least  75%  of  rated power output.  The specific gravity of the solution in the battery  should  be  1.225.    The  battery  should  be  held firmly  in  place.    The  battery  holder  must  not  put  too much stress on the battery. 2. The  cables  between  the  battery,  the  starter,  and  the ground of the engine must be the correct size.  Wires and cables must be free of corrosion.  The wires and the cables  should  have  cable  support  clamps  in  order  to prevent stress on the battery connections. 3. The  leads,  the  junctions,  the  switches,  and  the  panel instruments  which  relate  to  the  charging  system  must operate correctly. 4. The    alternator    and    the    drive    components    for    the alternator must operate correctly. Alternators Table 32 Tools Needed 6V-7070 Digital Multimeter 1 8T-0900 Ammeter 1 1. Put the positive lead "+" of the multimeter on the "Bat" terminal of the alternator.  Put the negative " lead on the ground terminal or on the frame of the alternator.  Put the   ammeter   around   the   positive   output   wire   of   the alternator. 2. Turn  off  all  electrical  accessories.    Turn  off  the  fuel  to the engine.  Crank the engine for 30 seconds.  Wait for two minutes in order to cool the starting motor.  If the electrical system appears to operate correctly, crank the engine again for 30 seconds. NOTE: Cranking   the   engine   for   30   seconds   partially discharges the batteries in order to do a charging test.      If   the   battery   has   a   low   charge,   do   not perform   this   step.      Jump   start   the   engine   or charge the battery before starting the engine. 3. Start the engine and run at full throttle. 4. Check  the  output  current  of  the  alternator.    The  initial charging  current  should  be  equal  to  the  minimum  full load  current  or  the  initial  charging  current  should  be greater  than  the  minimum  full  load  current.    Refer  to Specifications, "Alternator and Regulator for the correct minimum full load current at different rpm. 6-105