TM 5-6115-400-35
to speed and read current. (Higher
(a) Battery Discharge Method-By this
residual magnetism resulting from
method, the battery is partly
uncontrolled voltage during this test
discharged by cranking the-engine
will cause the voltage to regulate at
for 30 seconds with lights, and other
an abnormally low voltage after the
accessories turned on.
NEVER
jumper is removed.) To restore
USE THE CRANKING MOTOR
proper operation, the generator
FOR MORE THAN 30 SECONDS
must be "cycled", that is, stopped
AT A TIME WITHOUT PAUSING
and stared.'"(Do not attempt to
TO ALLOW THE CRANKING
check voltage. regulator after using
MOTOR
TO
COOL
OFF.
JUMPER LEAD METHOD until this
Excessive cranking will damage the
condition has been corrected.)
cranking motor. Immediately after
the cranking cycle, Start the engine
and allow the generator output to
f. Installation. Refer to TM 5-611-400 12.
increase to its maximum as
determined by the current regulator
34. Fuel Injection Pump
setting before rising battery voltage
causes the voltage regulator to
a. General.
operate.
Since battery voltage
(1) The fuel injection pump and governor are
recovers very quickly, this method
mounted on the left side of engine. The
requires prompt action.
camshaft of the pump is driven at one-
(b) Load
Method-If
a
load
half engine speed by the accessory drive
approximating the current regulator
through an adjustable pump coupling.
setting is placed across the battery
The pump plungers are lifted by the pump
during the time that the current
camshaft through tappet assemblies,
regulator setting test is made, the
located below the plungers and in contact
voltage will not increase sufficiently
with the pump camshaft. The plungers
to cause the voltage regulator to
are lowered by plunger springs.
operate. This load may be provided
(2) Fuel is supplied by the fuel transfer pump
by a carbon pile or other suitable
through the second stage fuel filter and
into the fuel sump (9, fig.14) of the fuel
(c) Jumper
Lead
Method-If
the
injection pump. surrounding the plungers
regulator cover is removed and a
(11). When a plunger is at the bottom of
jumper lead placed across the
its stroke, the fuel flows through the
voltage regulator contact points, the
plunger barrel above the plunger. The
voltage regulator cannot operate.
plunger moving upward closes the barrel
Consequently, the generator output
ports, and as it continues its upward
will increase to its maximum as
movement, the fuel now under pressure,
determined by the current regulator
opens the corresponding delivery valve
setting.
Lights and accessories
assembly and flows through the fuel
should be turned on during the test
injection line to the corresponding fuel
to prevent excessive voltage. To
injection nozzle, where it is injected into
adjust the current regulator setting,
the combustion chamber for that
turn the adjusting screw at the base
particular cylinder.
Delivery of fuel
of the unit thereby changing the
ceases when the helix (10) (upper edge of
spiral spring tension. Increasing the
the annular groove in the plunger) opens
tension will increase the current
the by-pass port in
setting.
After each change of
adjustment, reduce generator speed
until cutout relay opens, then return
36
