load of 18 amperes. Readjust the field
24-volt battery in series with each
rheostat as necessary to maintain the
other and connect the group between
voltage. Operate the engine accessory
the field pin socket of the electrical
generator for 15 minutes to attain
receptacle connector and the engine
operating temperature. Readjust the
accessory generator. Close the battery
voltage and amperage to the aforemen-
switch and adjust the field rheostat for
tioned values. If the rated voltage and
a reading of 24 volts on the voltmeter.
amperage cannot be maintained, re-
The ammeter reading should be be-
port the condition to direct support
tween 0.91 and 0.98 ampere. If the
maintenance.
current does not fall within this range,
inspect the engine accessory generator
f. Installation.
for defective terminals, internal con-
(1) Install the cover band and tighten the
nections, or field windings.
screw.
(2) Refer to figure 18 and install the gen-
(2) Motoring test. Connect a jumper be-
tween the field pin socket and the
erator.
(3) Momentarily connect a jumper lead
brush pin socket of the electrical re-
between the battery terminal and the
ceptacle connector. Connect a fully-
generator terminal to polarize the
charged, 24-volt battery and a battery
switch in series with each other and
generator.
between the brush pin socket of the
65. Starter
electrical receptacle connector and the
engine accessory generator. Close the
a. Removal. Refer to figure 18 and remove
battery switch. The armature should
the starter.
revolve in a clockwise direction as
b. Cleaning and Inspection.
viewed from the drive end. If the
(1) Clean the exterior of the starter with
armature does not turn freely in the
a cloth dampened with an approved
correct direction, inspect the genera-
cleaning solvent and dry thoroughly.
tor for incorrect assembly, defective
(2) Inspect the starter for breaks, cracks
bearings, poor brush contact, or a de-
or other damage. Replace a damaged
fective armature.
starter.
(3) Output test. Mount the engine acces-
(3) Inspect brushes for excessive wear
sory generator on a test bench and
and dirt. Replace brushes that are
couple it to a drive motor. Connect a
worn to less than one-half their origi-
field rheostat between the field pin
nal length. Clean dirt from brushes.
socket and the brush pin socket of
(4) Check brushes for freedom in holders
the electrical receptacle connector.
so that they make good contact with
Connect the negative terminal of a
the commutator. Inspect wire con-
fully-charged battery to the engine
nections.
accessory generator and connect the
(5) Inspect gear teeth on starting mecha-
positive terminal to one terminal of a
nism for wear or damage. Replace
reverse current relay. Connect the
starter if necessary.
other terminal of the relay to the brush
c. Testing.
pin socket of the electrical receptacle
(1) Use a test lamp circuit and test be-
connector. Connect a carbon pile rheo-
tween the insulated brush holder and
stat across the battery. Momentarily
brush end cover. If the lamp lights on
connect a jumper across the terminals
this test, the brush holder is grounded.
of the reverse current relay to polarize
Replace starter if necessary.
the engine accessory generator. Start
(2) Test between the grounded brush
the drive motor and adjust its speed
holder and brush end cover. If the
to 1,775 rpm. Adjust the field rheo-
lamp fails to light, replace starter if
stat for a reading of 28.5 volts on the
necessary.
voltmeter and adjust the carbon pile
rheostat until the ammeter shows a
d. Installation. Install the starter.
AGO 8166A
