GMC S Series 1994, Repair Manual

Page: 578 / 919

DISASSEMBLY OF THE SD-300 STARTER MOTOR
If the motor does not perform to specifications, it may
need to be disassembled for further testing of the com­
ponents. Normally, the starter motor should be disas­
sembled only so far as is necessary to make repair or
replacement of parts. As a precaution, it is suggested
that safety glasses be worn when disassembling or
assembling the starter motor.
Before disassembly, perform the electrical tests on
the solenoid described under “ Inspection and Repair”
later in this section.
FIELD FRAME
Disassemble (Figures 3 and 4) *
A. Clean the outside of the starter housing.
• Remove grease, oil, mud, etc.
B. Make scribe marks to show the relationship of the
drive housing, field frame, and end frame to aid in
assembly.
C. Note the position of the through-bolts.
• One bolt has a stud on the end.
1. Field coil strap (51) from the solenoid motor termi­
nal (figure 4).
2. Through-bolts (35 and 58).
3. End frame (41).
4. Brake washer (34) from the commutator end of the
armature shaft.
5. Field frame (57) from the drive housing (31) and
the armature assembly (9).
DRIVE END
* Disassemble (Figures 5, 6, and 7)
1. Armature from the drive housing by tilting the
armature to disengage the shift lever fingers (1)
from the drive collar (figure 5).
2. Drive assembly (32) from the armature shaft (9) as
follows:
A. Remove the thrust collar (17) from the armature
shaft.
B. Drive the stop collar (39) away from the pinion
stop retainer ring (37) by sliding a metal cylin­
der onto the armature shaft and with a hammer,
striking the metal cylinder against the stop col­
lar (figures 6 and 7).
C. Remove the pinion stop retainer ring from the
groove in the armature shaft.
• If the retainer ring is distorted during remov­
al, it must be replaced.
D. Slide the drive assembly and the stop collar off
the armature shaft.
1. Lever
2. Plunger
3. Solenoid
4. Bushing
5. Spring
8. Coil
9. Armature
11. Grommet
17. Thrust Collar
31. Housing
32. Drive Assembly
33. Brushes
34. Brake Washer
35. Bolt
36.
Screw
37. Retainer Ring
38. Holder
39. Pinion Stop Collar
40. Pin
41. Frame
43. Lever Shaft
44. Nut and Washer
45. Lead
46. Insulator
47. Shoe
48. Plate
57. Field Frame
58. Through Bolts
F9321