TOPIC 3. STARTER MOTOR

TM 10-3930-644-14 & P

TOPIC 3. STARTER MOTOR

A. DESCRIPTION

2. The armature shaft and bushings should be

coated with Delco-Remy Lubricant No. 1960954.

Starter motor is a series type field coil connection, four

brush construction, with armature supported by bushings

3. The roll type overrunning clutch requires no

at drive and commutator ends.

The two brushes

lubrication. However, the drive assembly should

connected to field coil leads are insulated in commutator

be wiped clean.

end frame and the two armature brushes are grounded.

CAUTION

Do not clean in any degreasing tank

Starter must never be used for more

or with grease dissolving solvents;

than 30 seconds at any one time.

this will dissolve the lubricant in the

Allow starter motor to cool for 2

clutch mechanism.

minutes before using again. Never

4. Avoid excessive lubrication.

use starter to move vehicle.

A solenoid switch mounted to the flange on the Starter

C. IN VEHICLE TEST

motor drive housing operates the overrunning clutch

drive by means of linkage and a shift lever. When the

Several checks, both visual and electrical, should be

starter switch closes the cranking circuit, the solenoid is

made in a defective cranking circuit to isolate trouble

energized, shifting the starter motor pinion into mesh

before removing any unit. Before removing a unit in a

with the engine flywheel ring gear and closing the main

defective cranking system, the following checks should

contacts located inside the solenoid. Battery current is

be made.

then directed to the motor causing the armature to

rotate. Cranking torque is transmitted by the clutch from

1. Determine the condition of the battery, follow the

the starter motor armature to tip flywheel ring gear. To

testing procedure outlined in BATTERY Section.

protect the' armature from excessive speed as the

engine starts, the clutch is designed to 'overrun" or turn

2. Inspect the wiring for frayed insulation or other

faster than the armature which permits the pinion to

damage. Replace any wiring, that is damaged.

disengage itself.

Inspect all connections to the starter motor

solenoid, ignition switch and battery, including all

B. MAINTENANCE

ground connections.

Clean and tighten all

connections and wiring as required.

The starter motor is a completely enclosed unit and

requires very little maintenance. However, to ensure

3. Inspect solenoid and ignition switch to determine

satisfactory operation, periodic inspections should be

their condition. Connect a Jumper lead around

made to make sure mounting and wiring connections ire

any switch suspected of being defective. If the

tight and in good condition. Solenoid switch should be

system functions properly using this method,

firmly mounted and all wiring connections should be

repair or replace the bypassed switch.

clean and tight. These inspections should also include

connections to battery and return circuit, loose or dirty

4. Check engine for tight bearings, pistons, heavy

connections anywhere in the circuit will cause high

oil, etc., which imposes extra heavy loads on

resistance and reduced cranking efficiency.

When

starter motor.

mounting and wiring connections are kept in good

condition, and motor responds instantly and cranks

D. STARTER MOTOR REMOVAL

engine when switch is closed, motor may be considered

to be in satisfactory condition and disassembly is

Due to starter motor being completely enclosed, it must

unnecessary.

be removed from the engine any time it requires service.

Starter motor under normal operating conditions will not

1. Lift operator's seat and swing open right hand

require lubrication except during overhaul.

side panel.

When the motor is disassembled for any reason,

2. Disconnect all electrical leads from starter motor

lubricate as follows:

or starter motor solenoid.

3. Remove mounting bolts which attach starter

1. Oil wicks should be resaturated.

motor to flywheel housing.

R-146-1

3-91