2001 DODGE RAM change time

(7) Install caliper, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- INSTALLATION) (Refer to 5 - BRAKES/HYDRAU-
LIC/MECHANICAL/DISC BRAKE CALIPERS -
INSTALLATION).
(8) Install wheel and tire assemblies and lower
vehicle, (Refer to 22 - TIRES/WHEELS/WHEELS -
STANDARD PROCEDURE).
(9) Apply brakes several times to seat caliper pis-
tons and brake shoes and obtain firm pedal.(10) Top off master cylinder fluid level.
INSTALLATION - FRONT
(1) Bottom pistons in caliper bore with C-clamp.
Place an old brake shoe between a C-clamp and cal-
iper piston.
(2) Clean caliper mounting adapter and anti-rattle
springs.
(3) Lubricate anti-rattle springs with Mopar brake
grease.
(4) Install anti-rattle springs.
NOTE: Anti-rattle springs are not interchangeable.
(5) Install inboard brake shoe in adapter.
(6) Install outboard brake shoe in adapter.
(7) Tilt the bottom of the caliper over rotor and
under adapter. Then push the top of the caliper down
onto the adapter.
(8) Install caliper, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- INSTALLATION).
(9) Install wheel and tire assemblies and lower
vehicle, (Refer to 22 - TIRES/WHEELS/WHEELS -
STANDARD PROCEDURE).
(10) Apply brakes several times to seat caliper pis-
tons and brake shoes and obtain firm pedal.
(11) Top off master cylinder fluid level.
INSTALLATION - REAR BRAKE SHOES-11 inch
(1) Clean and inspect individual brake compo-
nents, (Refer to 5 - BRAKES/HYDRAULIC/ME-
CHANICAL/DRUM - CLEANING).
(2) Lubricate anchor pin and brake shoe contact
pads on support plate with high temperature grease
or Lubriplate (Fig. 50).
Fig. 48 Shoe Hold-Down Springs
Fig. 49 Brake Shoe Removal
Fig. 50 Shoe Contact Surfaces
1 - ANCHOR PIN
2 - SUPPORT PLATE
3 - SHOE CONTACT SURFACES
BR/BEBRAKES 5 - 27
BRAKE PADS/SHOES (Continued)

The drum forces both brake shoes to move in the
same direction of rotation. Servo action begins with
the primary brake shoe which begins to wedge (or
wrap) itself against the rotating drum surface. This
force is transmitted equally to the secondary brake
shoe through the adjuster screw and anchor pin. The
net result is that each shoe helps the other exert
extra force against the drum. It is servo action that
creates the wedging (or wrap) effect which produces
increased force on the drum braking surface.
All drum brake assemblies are equipped with a self
adjusting mechanism. The components forming the
mechanism consist of the: adjuster screw, adjuster
lever, actuating lever (11 inch brake), lever return
spring and the adjuster lever spring. The adjuster
lever on the 12 inch brake, is also equipped with a
lever and tension spring.
The adjuster mechanism performs two important
functions. First, is in maintaining proper brake shoe
operating clearance. And second, is to maintain brake
pedal height. The mechanism does so, by adjusting
the shoes in small increments to compensate for lin-
ing wear. The adjustment process is continuous
throughout the useful life of the brake lining.
The adjuster components are all connected to the
secondary brake shoes. Actual adjustment only
occurs during reverse brake stops. Secondary brake
shoe movement (during reverse stops), is what acti-
vates the adjuster components.
In operation, secondary shoe movement causes the
adjuster lever spring to exert pull on the lever. This
pivots the lever away from the adjuster screw teeth.
When the stop is completed and the brakes released,
the adjuster lever pivots back to a normal position. It
is during this return movement of the lever when
adjustment occurs. At this point, the lever comes
back into contact with the adjuster screw teeth as it
moves upward. The lever will then rotate the
adjuster screw one or two teeth as needed for adjust-
ment.
NOTE: The adjustment process requires a complete
stop to actually occur. Rolling stops will NOT acti-
vate the adjuster components. In addition, the
adjuster screws are left and right hand parts and
must NOT be interchanged.
DIAGNOSIS AND TESTING - BRAKE DRUM
The maximum allowable diameter of the drum
braking surface is indicated on the drum outer edge.
Generally, a drum can be machined to a maximum of
1.52 mm (0.060 in.) oversize. Always replace the
drum if machining would cause drum diameter to
exceed the size limit indicated on the drum.
BRAKE DRUM RUNOUT
Measure drum diameter and runout with an accu-
rate gauge. The most accurate method of measure-
ment involves mounting the drum in a brake lathe
and checking variation and runout with a dial indi-
cator.
Variations in drum diameter should not exceed
0.069 mm (0.0028 in.). Drum runout should not
exceed 0.18 mm (0.007 in.) out of round. Machine the
drum if runout or variation exceed these values.
Replace the drum if machining causes the drum to
exceed the maximum allowable diameter.
STANDARD PROCEDURE - BRAKE DRUM
MACHINING
The brake drums can be machined on a drum lathe
when necessary. Initial machining cuts should be lim-
ited to 0.12 - 0.20 mm (0.005 - 0.008 in.) at a time as
heavier feed rates can produce taper and surface
variation. Final finish cuts of 0.025 to 0.038 mm
(0.001 to 0.0015 in.) are recommended and will gen-
erally provide the best surface finish.
Be sure the drum is securely mounted in the lathe
before machining operations. A damper strap should
always be used around the drum to reduce vibration
and avoid chatter marks.
The maximum allowable diameter of the drum
braking surface is stamped or cast into the drum
outer edge.
CAUTION: Replace the drum if machining will cause
the drum to exceed the maximum allowable diame-
ter.
CLEANING
Clean the individual brake components, including
the support plate and wheel cylinder exterior, with a
water dampened cloth or with brake cleaner. Do not
use any other cleaning agents. Remove light rust and
scale from the brake shoe contact pads on the sup-
port plate with fine sandpaper.
INSPECTION
As a general rule, riveted brake shoes should be
replaced when worn to within 0.78 mm (1/32 in.) of
the rivet heads. Bonded lining should be replaced
when worn to a thickness of 1.6 mm (1/16 in.).
Examine the lining contact pattern to determine if
the shoes are bent or the drum is tapered. The lining
should exhibit contact across its entire width. Shoes
exhibiting contact only on one side should be
replaced and the drum checked for runout or taper.
Inspect the adjuster screw assembly. Replace the
assembly if the star wheel or threads are damaged,
or the components are severely rusted or corroded.
BR/BEBRAKES 5 - 33
DRUM (Continued)

ENGINE COOLANT
THERMOSTAT - 3.9L/5.2L/5.9L
DESCRIPTION
CAUTION: Do not operate an engine without a ther-
mostat, except for servicing or testing.
The thermostat on the 3.9L, 5.2L and 5.9L gas
powered engines is located beneath the thermostat
housing at the front of the intake manifold (Fig. 15).
The thermostat is a wax pellet driven, reverse pop-
pet choke type.
Coolant leakage into the pellet container will cause
the thermostat to fail in the open position. Thermo-
stats very rarely stick. Do not attempt to free a ther-
mostat with a prying device.
The same thermostat is used for winter and sum-
mer seasons. An engine should not be operated with-
out a thermostat, except for servicing or testing.
Operating without a thermostat causes longer engine
warmup time, unreliable warmup performance,
increased exhaust emissions and crankcase condensa-
tion that can result in sludge formation.
OPERATION
The wax pellet is located in a sealed container at
the spring end of the thermostat. When heated, the
pellet expands, overcoming closing spring tension
and water pump pressure to force the valve to open.
DIAGNOSIS AND TESTINGÐTHERMOSTAT
ON-BOARD DIAGNOSTICS
Allgasoline powered modelsare equipped with
On-Board Diagnostics for certain cooling system com-
ponents. Refer to On-Board Diagnostics (OBD) in the
Diagnosis section of this group for additional infor-
mation. If the powertrain control module (PCM)
detects low engine coolant temperature, it will record
a Diagnostic Trouble Code (DTC) in the PCM mem-
ory. Do not change a thermostat for lack of heat as
indicated by the instrument panel gauge or by poor
heater performance unless a DTC is present. Refer to
the Diagnosis section of this group for other probable
causes. For other DTC numbers, (Refer to 25 - EMIS-
SIONS CONTROL - DESCRIPTION).
The DTC can also be accessed through the DRB
scan tool. Refer to the appropriate Powertrain Diag-
nostic Procedures information for diagnostic informa-
tion and operation of the DRB scan tool.
REMOVAL
WARNING: DO NOT LOOSEN RADIATOR DRAIN-
COCK WITH SYSTEM HOT AND PRESSURIZED.
SERIOUS BURNS FROM COOLANT CAN OCCUR.
Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
If thermostat is being replaced, be sure that
replacement is specified thermostat for vehicle model
and engine type.
Factory installed thermostat housings on 3.9L,
5.2L and 5.9L engines are installed on a gasket with
an anti-stick coating. This will aid in gasket removal
and clean-up.
(1) Disconnect negative battery cable at battery.
(2) Drain cooling system until coolant level is
below thermostat (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(3) Air Conditioned vehicles: Remove support
bracket (generator mounting bracket-to-intake mani-
fold) located near rear of generator (Fig. 16).
NOTE: On air conditioning equipped vehicles, the
generator must be partially removed.
Fig. 15 ThermostatÐ5.2L and 5.9L Gas Powered
Engines
1 - THERMOSTAT HOUSING
2 - GASKET
3 - INTAKE MANIFOLD
4 - THERMOSTAT
5 - MACHINED GROOVE
BR/BEENGINE 7 - 49

ENGINE COOLANT
THERMOSTAT - 8.0L
DESCRIPTION
CAUTION: Do not operate an engine without a ther-
mostat, except for servicing or testing.
The thermostat on all gas powered engines is
located beneath the thermostat housing at the front
of the intake manifold (Fig. 22).
The thermostat is a moveable sleeve type.
Coolant leakage into the pellet container will cause
the thermostat to fail in the open position. Thermo-
stats very rarely stick. Do not attempt to free a ther-
mostat with a prying device.
The same thermostat is used for winter and sum-
mer seasons. An engine should not be operated with-
out a thermostat, except for servicing or testing.
Operating without a thermostat causes longer engine
warmup time, unreliable warmup performance,
increased exhaust emissions and crankcase condensa-
tion that can result in sludge formation.
OPERATION
The wax pellet is located in a sealed container at
the spring end of the thermostat. When heated, the
pellet expands, overcoming closing spring tension
and water pump pressure to force the valve to open.
DIAGNOSIS AND TESTINGÐTHERMOSTAT
ON-BOARD DIAGNOSTICS
Allgasoline powered modelsare equipped with
On-Board Diagnostics for certain cooling system com-
ponents. Refer to On-Board Diagnostics (OBD) in the
Diagnosis section of this group for additional infor-
mation. If the powertrain control module (PCM)
detects low engine coolant temperature, it will record
a Diagnostic Trouble Code (DTC) in the PCM mem-
ory. Do not change a thermostat for lack of heat as
indicated by the instrument panel gauge or by poor
heater performance unless a DTC is present. Refer to
the Diagnosis section of this group for other probable
causes. For other DTC numbers, (Refer to 25 - EMIS-
SIONS CONTROL - DESCRIPTION).
The DTC can also be accessed through the DRB
scan tool. Refer to the appropriate Powertrain Diag-
nostic Procedures information for diagnostic informa-
tion and operation of the DRB scan tool.
REMOVAL
WARNING: DO NOT LOOSEN THE RADIATOR
DRAINCOCK WITH THE SYSTEM HOT AND PRES-SURIZED. SERIOUS BURNS FROM THE COOLANT
CAN OCCUR.
Do not waste reusable coolant. If the solution is
clean, drain the coolant into a clean container for
reuse.
If the thermostat is being replaced, be sure that
the replacement is the specified thermostat for the
vehicle model and engine type.
A rubber lip-type seal with a metal shoulder is
pressed into the intake manifold beneath the thermo-
stat (Fig. 23).
(1) Disconnect negative battery cable at battery.
(2) Drain cooling system until coolant level is
below thermostat (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
Fig. 22 ThermostatÐ8.0L V-10 Engine
1 - COOLANT TEMP. SENSOR (FOR PCM)
2 - HEATER SUPPLY FITTING
3 - BOLTS (6)
4 - HOUSING WITH INTEGRAL SEAL
5 - THERMOSTAT
6 - RUBBER LIP SEAL
7 - TEMP. GAUGE SENDING UNIT
7 - 52 ENGINEBR/BE

Audio System Diagnosis
CONDITION POSSIBLE CAUSE CORRECTION
NO/POOR TAPE
OPERATION1. Faulty tape. 1. Insert known good tape and test operation.
2. Foreign objects behind
tape door.2. Remove foreign objects and test operation.
3. Dirty cassette tape
head.3. Clean head with Mopar Cassette Head Cleaner.
4. Faulty tape deck. 4. Exchange or replace radio, if required.
NO COMPACT DISC
OPERATION1. Faulty CD. 1. Insert known good CD and test operation.
2. Foreign material on
CD.2. Clean CD and test operation.
3. Condensation on CD
or optics.3. Allow temperature of vehicle interior to stabilize and test
operation.
4. Faulty CD player. 4. Exchange or replace radio, if required.
SPECIAL TOOLS
AUDIO SYSTEMS
ANTENNA BODY & CABLE
DESCRIPTION
The antenna body and cable are not readily visible
in their installed positions in the vehicle. The most
visible component of the antenna body and cable are
the antenna adapter and the antenna cap nut, which
are located on the top of the right front fender panel
of the vehicle, near the right end of the cowl plenum.
The antenna body and cable are secured below the
fender panel by the antenna cap nut through a pre-
fabricated and dedicated mounting hole in the top of
the right front fender. The primary coaxial antenna
cable is then routed beneath the fender sheet metal
and through a prefabricated and dedicated cable
entry hole in the right cowl side panel into the inte-
rior of the vehicle. Inside the vehicle, the primary
coaxial cable is connected to a secondary instrument
panel antenna coaxial cable with an in-line connector
that is located behind the right end of the instrumentpanel. The secondary coaxial cable is then routed
behind the instrument panel to the back of the radio.
The factory-installed radio antenna body and cable
consists of the following components:
²Antenna adapter- The antenna adapter is
sometimes also referred to as the antenna bezel or
escutcheon.
²Antenna body- The die cast white metal
antenna body is the mating structure between the
antenna mast and the primary antenna coaxial cable.
²Antenna cable- This vehicle uses a two-piece
antenna coaxial cable. The primary antenna cable is
integral to the antenna body, and the secondary
antenna cable connects the primary cable to the
radio.
²Antenna cap nut- The antenna cap nut is a
special, bright-plated threaded fastener that captures
the antenna adapter and retains the antenna body to
the fender sheet metal.
The components of the radio antenna body and
cable cannot be adjusted or repaired. All factory-in-
stalled radios automatically compensate for radio
antenna trim. Therefore, no antenna trimmer adjust-
ment is required or possible after replacing the
antenna body and cable or the radio. If an antenna
body and cable component is damaged or faulty, it
must be replaced. Other than the primary antenna
cable, which is integral to the antenna body, the indi-
vidual components of the antenna are available for
service replacement.
OPERATION
The antenna body and cable connects the antenna
mast to the radio. The radio antenna is an electro-
magnetic circuit component used to capture radio fre-
quency signals that are broadcast by local
Antenna Nut Wrench C-4816
8A - 4 AUDIOBR/BE
AUDIO (Continued)

NOTE: ECM Outputs:
After inputs are received by the ECM, certain sen-
sors, switches and components are controlled or reg-
ulated by the ECM. These are consideredECM
Outputs.These outputs are for:
²CCD bus (+) circuits
²CCD bus (-) circuits
²CKP and APPS outputs to the PCM
²Data link connection for DRB scan tool
²Five volt sensor supply
²Fuel injection pump
²Fuel injection pump relay
²(FPCM) Fuel Pump Control Module
²Fuel transfer (lift) pump
²Intake manifold air heater relays #1 and #2 con-
trol circuits
²Malfunction indicator lamp (Check engine lamp)
²Oil pressure gauge/warning lamp
²PCM
²Wait-to-start warning lamp
²Water-In-Fuel (WIF) warning lamp
REMOVAL
The ECM is bolted to the engine block behind the
fuel filter (Fig. 16).
(1) Record any Diagnostic Trouble Codes (DTC's)
found in the PCM or ECM.To avoid possible voltage spike damage to either
the Powertrain Control Module (PCM) or ECM, igni-
tion key must be off, and negative battery cables
must be disconnected before unplugging ECM con-
nectors.
(2) Disconnect both negative battery cables at both
batteries.
(3) Remove 50±way electrical connector bolt at
ECM (Fig. 16). Note: Connector bolt is female 4mm
hex head. To remove bolt, use a ball-hex bit or ball-
hex screwdriver such as Snap-Ont4mm SDABM4
(5/32º may also be used). As bolt is being removed,
very carefully remove connector from ECM.
(4) Remove three ECM mounting bolts and remove
ECM from vehicle.
INSTALLATION
Do not apply paint to back of ECM. Poor ground
will result.
(1) Clean ECM mounting points at engine block.
(2) Position ECM to engine block and install 3
mounting bolts. Tighten bolts to 24 N´m (18 ft. lbs.).
(3) Check pin connectors in ECM and 50±way con-
nector for corrosion or damage. Repair as necessary.
(4) Clean pins in 50±way electrical connector with
a quick-dry electrical contact cleaner.
(5) Very carefully install 50±way connector to
ECM. Tighten connector hex bolt.
(6) Install battery cables.
(7)Turn key to ON position. Without starting
engine, slowly press throttle pedal to floor and
then slowly release. This step must be done
(one time) to ensure accelerator pedal position
sensor calibration has been learned by ECM. If
not done, possible DTC's may be set.
(8) Use DRB scan tool to erase any stored compan-
ion DTC's from PCM.
POWERTRAIN CONTROL
MODULE
DESCRIPTION - PCM
The Powertrain Control Module (PCM) is located
in the engine compartment (Fig. 17). The PCM is
referred to as JTEC.
DESCRIPTION - MODES OF OPERATION
As input signals to the Powertrain Control Module
(PCM) change, the PCM adjusts its response to the
output devices. For example, the PCM must calculate
different injector pulse width and ignition timing for
idle than it does for wide open throttle (WOT).
The PCM will operate in two different modes:
Open Loop and Closed Loop.
Fig. 16 Engine Control Module (ECM) Location and
Mounting
1 - ENGINE CONTROL MODULE (ECM)
2 - HEX HEADED BOLT
3 - 50-WAY CONNECTOR
4 - FUEL TRANSFER PUMP
5 - MOUNTING BOLTS (3)
8E - 14 ELECTRONIC CONTROL MODULESBR/BE
ENGINE CONTROL MODULE (Continued)

lead dioxide (positive plate) or sponge lead (negative
plate). Insulators or plate separators made of a non-
conductive material are inserted between the positive
and negative plates to prevent them from contacting
or shorting against one another. These dissimilar
metal plates are submerged in a sulfuric acid and
water solution called an electrolyte.
The factory-installed battery has a built-in test
indicator (hydrometer). The color visible in the sight
glass of the indicator will reveal the battery condi-
tion. Refer to Standard Procedures for the proper
built-in indicator test procedures.The factory-in-
stalled low-maintenance battery has non-re-
movable battery cell caps.Water cannot be added
to this battery. The battery is not sealed and has
vent holes in the cell caps. The chemical composition
of the metal coated plates within the low-mainte-
nance battery reduces battery gassing and water
loss, at normal charge and discharge rates. There-
fore, the battery should not require additional water
in normal service. Rapid loss of electrolyte can be
caused by an overcharging condition. Be certain to
diagnose the charging system before returning the
vehicle to service. Refer to Charging System for the
proper charging system diagnosis and testing proce-
dures.
OPERATION
The battery is designed to store electrical energy in
a chemical form. When an electrical load is applied to
the terminals of the battery, an electrochemical reac-
tion occurs. This reaction causes the battery to dis-
charge electrical current from its terminals. As the
battery discharges, a gradual chemical change takes
place within each cell. The sulfuric acid in the elec-
trolyte combines with the plate materials, causing
both plates to slowly change to lead sulfate. At the
same time, oxygen from the positive plate material
combines with hydrogen from the sulfuric acid, caus-
ing the electrolyte to become mainly water. The
chemical changes within the battery are caused by
the movement of excess or free electrons between the
positive and negative plate groups. This movement of
electrons produces a flow of electrical current
through the load device attached to the battery ter-
minals.
As the plate materials become more similar chem-
ically, and the electrolyte becomes less acid, the volt-
age potential of each cell is reduced. However, by
charging the battery with a voltage higher than that
of the battery itself, the battery discharging process
is reversed. Charging the battery gradually changes
the sulfated lead plates back into sponge lead and
lead dioxide, and the water back into sulfuric acid.
This action restores the difference in the electron
charges deposited on the plates, and the voltage
potential of the battery cells. For a battery to remain
useful, it must be able to produce high-amperage cur-
rent over an extended period. A battery must also be
able to accept a charge, so that its voltage potential
may be restored.
The battery is vented to release excess hydrogen
gas that is created when the battery is being charged
or discharged. However, even with these vents,
hydrogen gas can collect in or around the battery. If
hydrogen gas is exposed to flame or sparks, it may
ignite. If the electrolyte level is low, the battery may
arc internally and explode. If the battery is equipped
with removable cell caps, add distilled water when-
ever the electrolyte level is below the top of the
plates. If the battery cell caps cannot be removed, the
battery must be replaced if the electrolyte level
becomes low.
DIAGNOSIS AND TESTING - BATTERY
The battery must be completely charged and the
top, posts and terminal clamps should be properly
cleaned and inspected before diagnostic procedures
are performed. Refer to Battery System Cleaning for
the proper cleaning procedures, and Battery System
Inspection for the proper battery inspection proce-
dures. Refer to Standard Procedures for the proper
battery charging procedures.
Fig. 4 Low-Maintenance Battery - Typical
1 - POSITIVE POST
2 - VENT
3 - CELL CAP
4 - TEST INDICATOR
5 - CELL CAP
6 - VENT
7 - NEGATIVE POST
8 - GREEN BALL
9 - ELECTROLYTE LEVEL
10 - PLATE GROUPS
11 - LOW-MAINTENANCE BATTERY
BR/BEBATTERY SYSTEM 8F - 7
BATTERY (Continued)

ENGINE STARTER MOTOR
DESCRIPTION
The starter motors used for the 5.9L diesel engine
and the 8.0L gasoline engine available in this model
are not interchangeable with each other, or with the
starter motors used for the other available engines.
The starter motors used for the 3.9L, 5.2L and the
5.9L gasoline engines available in this model are
interchangeable.
The starter motor for the 5.9L diesel engine is
mounted with three screws to the flywheel housing
on the left side of the engine. The starter motor for
the 8.0L gasoline engine is mounted with two screws
to the flange on the left rear corner of the engine
block, while the starter motors for all of the other
engines are mounted with one screw, a stud and a
nut to the manual transmission clutch housing or
automatic transmission torque converter housing and
are located on the left side of the engine.
Each of these starter motors incorporates several
of the same features to create a reliable, efficient,
compact, lightweight and powerful unit. The electric
motors of all of these starters have four brushes con-
tacting the motor commutator, and feature four elec-
tromagnetic field coils wound around four pole shoes.
The 3.9L, 5.2L, 5.9L and 8.0L gasoline engine starter
motors are rated at 1.4 kilowatts (about 1.9 horse-
power) output at 12 volts, while the 5.9L diesel
engine starter motor is rated at 2.7 kilowatts (about
3.6 horsepower) output at 12 volts.
All of these starter motors are serviced only as a
unit with their starter solenoids, and cannot be
repaired. If either component is faulty or damaged,
the entire starter motor and starter solenoid unit
must be replaced.
OPERATION
These starter motors are equipped with a gear
reduction (intermediate transmission) system. The
gear reduction system consists of a gear that is inte-
gral to the output end of the electric motor armature
shaft that is in continual engagement with a larger
gear that is splined to the input end of the starter
pinion gear shaft. This feature makes it possible to
reduce the dimensions of the starter. At the same
time, it allows higher armature rotational speed and
delivers increased torque through the starter pinion
gear to the starter ring gear.
The starter motors for all engines are activated by
an integral heavy duty starter solenoid switch
mounted to the overrunning clutch housing. This
electromechanical switch connects and disconnects
the feed of battery voltage to the starter motor, also
engaging and disengaging the starter pinion gear
with the starter ring gear.All starter motors use an overrunning clutch and
starter pinion gear unit to engage and drive a starter
ring gear that is integral to the flywheel (manual
transmission), torque converter or torque converter
drive plate (automatic transmission) mounted on the
rear crankshaft flange.
DIAGNOSIS AND TESTING - STARTER MOTOR
Correct starter motor operation can be confirmed
by performing the following free running bench test.
This test can only be performed with starter motor
removed from vehicle. Refer to Starter Specifications
for starter motor specifications.
(1) Remove starter motor from vehicle. Refer to
Starter MotorRemoval and Installation.
(2) Mount starter motor securely in a soft-jawed
bench vise. The vise jaws should be clamped on
mounting flange of starter motor. Never clamp on
starter motor by field frame.
(3) Connect suitable volt-ampere tester and 12-volt
battery to starter motor in series, and set ammeter to
100 ampere scale (250 ampere scale for diesel engine
starters). See instructions provided by manufacturer
of volt-ampere tester being used.
(4) Install jumper wire from solenoid terminal to
solenoid battery terminal. The starter motor should
operate. If starter motor fails to operate, replace
faulty starter motor assembly.
(5) Adjust carbon pile load of tester to obtain free
running test voltage. Refer to Specifications for the
starter motor free running test voltage specifications.
(6) Note reading on ammeter and compare this
reading to free running test maximum amperage
draw. Refer to Specifications for starter motor free
running test maximum amperage draw specifica-
tions.
(7) If ammeter reading exceeds maximum amper-
age draw specification, replace faulty starter motor
assembly.
STARTER MOTOR SOLENOID
This test can only be performed with starter motor
removed from vehicle.
(1) Remove starter motor. Refer toStarter Motor
Removal and Installation.
(2) Disconnect wire from solenoid field coil termi-
nal.
(3) Check for continuity between solenoid terminal
and solenoid field coil terminal with continuity tester
(Fig. 7). There should be continuity. If OK, go to Step
4. If not OK, replace faulty starter motor assembly.
(4) Check for continuity between solenoid terminal
and solenoid case (Fig. 8). There should be continuity.
If not OK, replace faulty starter motor assembly.
BR/BESTARTING 8F - 39