TM 10-3930-653-14&P (4)   Increase    engine    speed    to    2,500    rpm  gradually, and  continue  operation  for  several  minutes.  Make  sure that the amperage is less than 5A after several minutes have elapsed. Lower engine speed to idling speed. Note: If several minutes have elapsed and   amperage   did   not   lower   below 5A,    battery    is     not     fully     charged. Replace  battery  with  a  fully  charged one. (5)   Increase  engine  speed  to  2,500  rpm  gradually,  and read      voltage       indicated        on        voltmeter.    Compare regulating    voltage    against    rated  regulating  voltage  at ambient     temperature     of     regulator     at     the     time     of measurement. Note: When two  to  three  minutes  are elapsed after starting regulator operation, voltage rises approximately    0.3    V     from     normal voltage  due  to  self-heating.  Thus,  be sure  to  measure  voltage  within  one minute after starting operation. When  measurement  cannot  be  made within one minute, cease operation at once and measure again after cooling regulator.      Do   not   measure   output voltage     immediately     after     driving. When    measuring,    make    sure    that regulator is cold. Fig. 4-198. 4-7-6-5.  ADJUSTMENT (1)   VOLTAGE REGULATOR As    a    result    of    the    above    measurement.    When regulating voltage is not the rated value. Adjust regulator in accordance with following instructions. Fig. 4-199.  Construction of Voltage Regulator Unit: mm (in) Back gap 0.8 to 1.1 (0.031 to 0.043) Air gap 0.8 to 1.2 (0.031 to 0.047) Point gap 0.3 to 0.4 (0.012 to 0.016) (1)   Adjusting back gap Loose  armature  hinge  screw  and  adjust  position  by sliding armature. 4-111