GMC 4000 Series Service Manual page 407

Sec. 6Y
Page 396
STANDARD
Series LV/LA-4000; EM-4500M/V; EM-5500A/M/V;
SM-5500M/Y; E M -6 5 0 0 A /V ...............................................
Series SM-6500M/Y
Series ES-4500V
Series PS-4500P; ES-5500V; SS-5500M
S eries DLA/DLV-4000; EG-5500A/V; S G -5 5 0 0 M /Y ..............
EG-6500A/V
OPTIONAL
Series ES-4500V; ES-5500V; SS-5500M
GENERAL
The solenoid operated, overrunning clutch type
starting motors used as standard and optional
equipment on vehicles covered by this manual are
shown in the "Model Application Chart" above.
DESCRIPTION
The overrunning clutch type starting motors
(fig. 1), are of the enclosed shift lever type.
The drive end housing is extended to enclose
the entire shift lever mechanism and solenoid
plunger. The solenoid flange is mounted on drive
end housing, with sealing compound used between
flange and field frame. A compression type shift
lever return spring located inside the solenoid
case is used to operate the overrunning clutch. On
gasoline engine models, primary circuit to ignition
coil is fed from solenoid while the starter is op­
erating.
Positive lubrication is provided to bronze
bushings in commutator end frame, in the drive
end frame and in the nose housing by oil saturated
wicks that project through each bushing and con­
tact the armature shaft.
On some models, a starter interlock is used
to prevent the starter from, being engaged while the
engine is running and to prevent starter over­
speeding by holding starter in engaged position.
STARTING SYSTEM OPERATION
The starting system consists of the battery,
starting motor, including the drive assembly which
engages the flywheel ring gear during cranking,
the starter solenoid, mounted on the starting motor
for shifting the drive assembly and closing the
motor circuit and the ignition or control switch
which, when in the "START" position connects a
lead from the battery to the solenoid switch. Dur­
ing cranking, the ignition switch (gasoline engine
G M C S E R V I C E M A N U A L
Sta/itUuf Stfiiem
MODEL APPLICATION CHART
.......................................................................
...............................................................................
......................................................................................
models) also connects the battery directly to the
ignition coil.
noid operated shift lever slides the pinion into
mesh with the flywheel ring gear teeth. The rotary
motion between pinion and ring gear, provided by
spiral splines on clutch shaft, normally relieves
tooth abutment on the first attempt to engage pin­
ion and ring gear. A protective sleeve located on
the spiral spline acts as a stop for the pinion when
extreme tooth abutment occurs. This lim its the
clutch travel, preventing switch contacts in the
solenoid from closing. Therefore, the armature
cannot rotate before pinion is engaged properly,
preventing damage to pinion and ring gear. A
second attempt to engage rotates pinion enough to
assure proper engagement.
SERIES SG-5500; EG-5500-6500
hicles
D iesel engine to prevent starter over-speeding by
breaking starter solenoid to engine control switch
circuit when engine reaches approximately 400-600
rpm. This system also prevents starter pinion
from engaging a running flywheel by breaking cir­
cuit between engine control switch and starter sole­
noid while engine is running. This system is con­
trolled by output at "R" terminal of the generator
as shown in figure 2 or 3.
PART NUMBER
1107375
1107376
1108368
.................................... 1108360
1113686
1113686
.................................... 1108372
CAUTION: If a remote switch is used
to operate starter, the primary wire must
be disconnected from coil negative term­
inal and ignition switch must be turned on.
Failure to do this will result in damaged
grounding circuit in ignition switch.
When starter circuit is energized, the sole­
STARTER AUTOMATIC
DISENGAGEMENT AN D LOCK OUT
A starter interlock relay is used on these ve­
equipped with the D/DH-478 Toro-Flow