TM 5-3810-206-35
CHAPTER 3
ENGINE REPAIR INSTRUCTIONS
Section I. GENERATOR OR ALTERNATOR
(12) Remove four screws (1), external toothed
3-1.
General
lockwasher (2), and end cover (5) from frame (6).
The electrical energy required for operation of crane-
(13) Remove four nuts (33), lockwashers (11),
shovel lights while the engine is shut down, and the
screws (29), and brush plate (12) from frame (6).
starting motor, is furnished from storage batteries.
(14) Disengage four springs (32) from brush
Batteries are replenished when engine is running, by a
plate (12), then remove brush arm (30), spacer (31),
generator on units powered with engine model 687C-18-
springs (32), and brushes (9) from brush plate (12).
ES, or by an alternator on units powered with engine
(15) Remove two dowel pins (20) from frame
model D333TA. This section will describe alternator and
(13).
generator maintenance.
(16) Remove eight screws (27) then remove pole
shoes (25) and coils (21, 23, 24, and 26) as a unit, from
frame (13). Remove two insulators (22) from frame (13).
3-2.
Generator (for Engine Model 687C-18-ES)
(17) Remove four screws (19), lockwashers (11),
a. Removal and Installation. Refer to TM 5-3810-
and elbow (18) from frame (13).
206-12 and remove or install the generator.
(18) Remove four screws (14), lockwashers (11),
b. Disassembly or Reassembly.
and receptacle (15) from elbow (18).
(1) Loosen screw and remove cover band (28,
(19) Reassemble by reversing the procedures in
steps (1) through (18) above.
(2) Remove nut (46), washer (45), and cup (44)
c. Cleaning, Inspection, Test and Repair. Refer to
from armature (34).
TM 5-764 for instructions on cleaning, inspection,
(3) Use a suitable puller and remove sheave
testing, and repair of the generator.
(43) and fan (42) as a unit.
(4) Remove four screws (39), lockwasher (41),
3-3. Alternator (for Engine Model D333TA)
and fan (42) from sheave (43).
(5) Remove collar (10) from armature (34).
a. General. This alternator is a self-rectifying AC
(6) Position generator with drive end up;
generator. It contains a rectifier consisting of six diodes
remove six screws (48), lockwasher (4, and end frame
which changes the AC voltage produced in stator
(37) from frame (13).
windings to DC voltage.
A separate transistorized
(7) Remove armature (34) from frame (13), by
regulator controls the alternator output. Two brushes,
carefully lifting armature straight up and out of frame.
each riding on a separate slip ring, supplies direct
(8) Remove bearing (7) from armature (34).
current to rotor field windings in an amount demanded
(9) Remove six screws (47), lockwasher (11),
by regulator, thus controlling strength of the magnetic
plate (35), bearing (36), and plate (38) from frame (37).
field.
(10) Remove the screws (10) and lockwashers
b. Removal and Installation. Refer to TM 5-3810-
(11) from brush terminals of field coils (21, 23, 24, and
206-12 and remove or install the alternator.
26); from lead (8), receptacle (15), and from brush plate
c. Disassembly and Reas sembly. Disassemble as
(12).
required to accomplish inspection and repair in the
(11) Remove six screws (3), lockwasher (4), and
following order.
end frame (6) from frame (13).
3-1
