TM 9-4940-549-14&P
(h) Operate pump at 900 rpm, with wide open throttle and observe
transfer pump pressure. Pressure should be 70 to 75 psig. If
it is not, use a hex key wrench and adjust pressure regulating
spring by 1/4 turns, clockwise to raise pressure, counterclock-
wise to lower pressure.
(i) Perform automatic advance check as follows:
NOTE
Each mark on the timing window is 2
pump degrees.
1.
Check at 250 to 400 rpm for one
degree cam movement.
2.
Drain burettes for 30 second min-
imum.
3.
Check at 450 to 550 rpm for 3-1/2
degree cam movement.
(j) Perform speed droop adjustment as follows: (See table 8-1).
1.
At 900 rpm and wide open throttle adjust high idle screw
temporarily for 15-20 mm3 delivery per stroke.
2.
Raise pump speed to 927 rpm and turn the droop adjust-
ment cap assembly clockwise as viewed from the transfer
pump end of injection pump to obtain a delivery of 15-20
mm per stroke.
3.
Lower pump speed to 900 rpm and check full load delivery
rate. If 56-59 mm3 delivery rate i s not realized, repeat
steps 1 and 2 above until 56-59 mm3 is obtained.
4.
When step 3 requirements are met, lock the high idle adjust-
ing screw.
(k) Check delivery at 750 rpm. If delivery is not 55-58 mm3 per
stroke, repeat step (j) above until it is.
(l) Raise pump speed to 950 rpm and check for a delivery rate of
5 mm3 maximum delivery rate.
(m) Lower pump Sp eed to 900 rpm and de-energize the solenoid.
Check for 5 mm3 maximum delivery rate.
(n) At the same speed, energize the solenoid and check the manual
shutoff for the same delivery rate of 5mm3 maximum.
(o) At a pump speed of 200 rpm, repeat steps (n) and (9). Deliv-
ery shall be 2 mm3 maximum.
8-35
