fuel filter DODGE TRUCK 1993 Service Repair Manual

0 - 2
LUBRICATION
AND
MAINTENANCE

• Commercial service
When a vehicle is continuously subjected to severe
driving conditions, lubricate:
• Body components
• All the driveline coupling joints
• Steering linkage More often than normal driving conditions

DUSTY
AREAS
With this type of severe driving condition, special
care should be given to the:
• Engine air cleaner filter
• PCV filter
• Crankcase ventilation system
• Brake booster control valve air filter. Verify that the filters and the associated compo­
nents are clean. Also verify that they are functioning
effectively. This will minimize the amount of abra­ sive particles that enter the engine.

OFF-ROAD
(4WD)
OPERATION
After off-road (4WD) operation, inspect the under­
side of the vehicle. Inspect the:
• Tires
• Body structure
• Steering components
• Suspension components • Exhaust system
• Threaded fasteners

HARSH
SURFACE ENVIRONMENTS
After extended operation in harsh environments,
the brake drums, brake linings, and rear wheel bear­ ings should be inspected and cleaned. This will pre­
vent wear and erratic brake action.

ROUTINE MAINTENANCE
The following routine maintenance is recommended
on a monthly basis: TIRES—Inspect the tires for unusual wear/damage.
Determine if the inflation pressure is adequate for
the vehicle load. BATTERY—Inspect and clean the terminals.
Tighten the terminals if necessary. FLUIDS—Determine if the component fluid levels
are acceptable. Add fluid, if necessary. LIGHTS/ELECTRICAL—Test all the electrical sys­
tems in the vehicle for proper operation. It is also recommended that the engine oil and the
washer fluid level be determined at each fuel fill-up.

VEHICLE
NOISE CONTROL
Vehicles with a GVWR of 4 535 kg (10,000 lbs), or
more, are required to comply with Federal Exterior Noise Regulations (Fig. 2).
VEHICLE
NOISE
EMISSION
CONTROL INFORMATION

DATE
OF
VEHICLE
MANUFACTURE

THIS
VEHICLE CONFORMS
TO
U.S. EPA REGULATIONS FOR NOISE EMISSION

APPLICABLE
TO
MEDIUM
AND HEAVY
DUTY
TRUCKS. THE
FOLLOWING
ACTS OR THE CAUSING THEREOF BY ANY PERSON ARE PROHIBITED BY THE NOISE CONTROL ACT
OF 1972. (A) THE
REMOVAL
OR

RENDERING
INOPERATIVE, OTHER
THAN
FOR
PURPOSES
OF
MAINTENANCE,
REPAIR.
OR REPLACEMENT, OF ANY NOISE CONTROL DEVICE OR ELEMENT OF
DESIGN
(LISTED
IN
THE
OWNERS
MANUAL)
INCORPORATED
INTO
THIS
VEHICLE
IN COMPLIANCE
WITH
THE NOISE CONTROL
ACT:
(B) THE
USE
OF
THIS
VEHICLE
AFTER SUCH DEVICE
OR
ELEMENT
OF
DESIGN HAS BEEN REMOVED
OR
RENDERED
INOPERATIVE.

PU626D

Fig.
2 Vehicle
Noise
Emission
Control Information
Label

UNAUTHORIZED
DEFEAT
OF
NOISE
CONTROL COMPONENTS
Federal law prohibits removal, altering or other­
wise defeating any noise control component. This in­
cludes before or after the vehicle is in use. Federal
law also prohibits the use of a vehicle after a noise
control component is defeated.

REQUIRED MAINTENANCE/SERVICE
FOR
NOISE
CONTROL

The following maintenance is required after each
6-month or 9 600 km (6,000 miles) interval. This will
ensure that the vehicle noise control components are
operating properly.

EXHAUST SYSTEM
Inspect exhaust system for exhaust leaks and dam­
aged components. The exhaust hangers, clamps and
U-bolts should be attached and in good condition.
Burned or ruptured mufflers, damaged exhaust pipes should be replaced. Refer to Group 11—Exhaust Sys­
tem/Intake Manifold for service information.

AIR
FILTER
HOUSING/CANISTER
Inspect the air filter assembly for proper fit. Verify
the cover is securely attached to the housing/canis­
ter. Inspect all the air filter housing hoses for con­ nections. The gasket between the air filter housing and throttle body must be in good condition. The air
filter element should be clean and serviced according
to the maintenance schedule.

FUEL
REQUIREMENTS
GASOLINE
ENGINES
All engines require the use of unleaded gasoline to
reduce the effects of lead to the environment. Also unleaded fuel is necessary to prevent damage to the
catalytic converter/02 sensor. The fuel must have a
minimum octane rating of 87 based on the (R + M)/2
calculation method.

0 - 6
LUBRICATION
AND
MAINTENANCE
GASOLINE ENGINE MAINTENANCE SCHEDULE

HEAVY
DUTY
CYCLE

Inspection and service is also necessary anytime
a
malfunction is observed or suspected.
When both
time
and mileage
are
Miles (Thousand)

shewn,
follow
the
interval

which occurs first. Kilometers (Thousand) 6
12 18 24
30 36 42 48 54
60 66 72

78
82V2
84 90
96
102 108
When both
time
and mileage
are
Miles (Thousand)

shewn,
follow
the
interval

which occurs first. Kilometers (Thousand) 9.6 19 29
38 48 58 67 77
85 96 106 116
125 132
135
145
154 164
174

Coolant
Condition, Coolant
Hoses/Clamps
X
X X X
X X X X
X X X X
X X X
X X X

Exhaust
System
—
Check
X X X X X X X X X X X
X X X X X
X X

Oil
—
Change
(6
Months)
X X X X X X X
X X

X
X
X

X X X

X X
X

Oil
Filter
—
Change (2nd
Oil
Change)
X X X X
X X
X X
X

Drive Belt Tension
—
Inspect
&
Adjust
X' X
X1

X X' X

Drive Belts (V-Type)
—
Replace
X

Air
Filter/Air
Pump
Air
Filter
—
Replace
X X X
X

Crankcase
Inlet
Air
Filter
(6 &
8
Cyl.
Eng.
Only)
—
Clean
X X
X X

Spark
Plug
—
Replace
X X X

Fuel
Filter
—
Replace as necessary

Coolant
—
Flush/Replace
(36
months)
& 24
months/48
000 km

(30,000
miles)
thereafter
X
EGR
Valve
&
Tube
—
Replace X2

EGR
Tube
—
Clean Passengers
X2
PCV
Valve
—
Replace X2

Vacuum
Emission
Components
—
Replace
X

Ignition Timing
—
Adjust
to
Specs,
as necessary X
Ignition Cables, Distributor Cap
&
Rotor
—
Replace
X

Manifold Heat Control Valve
—
Lubricate
X

Battery
—
Replace X

Oxygen
Sensor
—
Replace
X2

1 For California vehicles, this maintenance is recommended
by
Chrysler Motors
to the
owner but, is not
required
to
maintain the
warranty
on the
air
pump drive
belt.

2 Requires
Emission
Maintenance Reminder Light.
If
so equipped, these parts
are to be
replaced
at the
indicated mileage,
or
when the
emissions
maintenance reminded light remains on continuously
with
the key in the
"on" position, whichever occurs first.
J9100-20

DIESEL
ENGINE
MAINTENANCE
SCHEDULE
HEAVY
DUTY
CYCLE
Inspection
and
service
is
also
necessary
any
time
a
malfunction
is
observed
or
suspected.

Iff both
time
and distance Miles (Thousand)
are listed, use the
interval

that
ends
first. Kilometers (Thousand) 6
12
18 24
30 36 42

4S
54
60 66
72 78
84 90 96
102 108
Iff both
time
and distance Miles (Thousand)
are listed, use the
interval

that
ends
first. Kilometers (Thousand) 9,6 19
29
38 48 58 67

77

85 96 106
116 125 135 145 154
164 174

Coolant
Condition, Coolant
Hoses/Clamps
(12 months)

Coolant
Flush/Replace (36 months) & 24 months/
48 000 km
(30,000
miles)
thereafter
O

Oil—Change
(6 months)
X X X
X X X
X X X X X
X X X X X X
X

Oil Filter—Replace (Every Oil Change)
X X X
X X X
X X
X X X
X
X X X X
X X

Drive Belts—Replace
As
Necessary
X X
X X X X

Air Filter—Replace
X X
X X

Air Filter—Clean (California Only) e

®

• •
Air
Filter
Canister—Clean
o o o
o

Fuel Filter—Service When Necessary

Injection
Pump
Timing & Engine Idle Speed—

Check
& Adjust
©

• 9 • • •
Underhood Rubber/Plastic Components—Inspect/Replace • • • • •

X
— All vehicles
O
— All
vehicles
except
California.
Recommended
for
California.
•
— California only.
Recommended
for all vehicles.

•
LUBRICATION AND MAINTENANCE
0 - 9 FLUID CAPACITIES

COOLING SYSTEM
QUARTS
LITERS

POWER STEERING PINTS

LITERS

3.9L ENGINE 15.1 14.3
ALL
2.7
1.28

5.2L ENGINE
(2WD)
17.0 16.1

REAR
AXLE
PINTS
LITERS

5.2L ENGINE
(4WD)
16.5 15.6

CHRYSLER
BVa
Inch
(210
mm) 4.4
2.08
5.9L ENGINE
(2WD)
15.5 14.7

CHRYSLER
9Va
Inch
(235
mm) 4.5
2.13
5.9L ENGINE
(4WD)
15.0 14.2
DANA
60 6.0
2.84
5.9L DIESEL ENGINE (MAN.TRANS.) 15.5 14.7
DANA
70 7.0

3.31
5.9L DIESEL ENGINE
(AUTO,
TRANS)
16.5 15.6
FRONT AXLE
PINTS

LITERS

ENGINE
CRANKCASE
QUARTS
LITERS

DANA
44
FBJ 5.6
2.65
3.9L,
5.2L & 5.9
ENGINES 4.0* 3.8*
DANA
60 F
6.5
3.07
5.9L DIESEL ENGINES 12.0*
11.4**

TRANSMISSION-AUTOMATIC

QUARTS
LITERS

FUEL TANK GALLON

LITERS
A
727 (5.9L
ENGINE) 8.4
7.9

STANDARD
3.9L & 5.2L ENGINES 22.0 83.0

A
998 (3.9L
ENGINE) 8.6
8.1
OPTIONAL 3.9L & 5.2L ENGINES 30.0 113.0

A
999 (5.2L
ENGINE) 8.6
8.1
5.9L ENGINE
{G
OR
D)
30.0 113.0

A
518 (5.2L & 5.9L
ENGINES) 10.2
9.6
AD 100
&
AW 100 34.0 128.0

TRANSMISSION-MANUAL
QUARTS
LITERS

TRANSFER
CASE
PINTS
LITERS

NV
4500
4.0
3.8

NP-205
4.5 2.13

GETRAG
360 (5
Speed)
3.5
3.3

NP-241
6.0
2.84
* Add
0.5 qt. or 0.45
liter
when
the oil filter
is
changed

*
*
Add
1 qt. or 0.9
liter
with
oil filter
change STARTING ASSISTANCE (JUMP STARTING)
WARNING:
DO NOT
ATTEMPT
TO
PUSH
OR
TOW
A
VEHICLE
TO
START
THE
ENGINE. UNBURNED FUEL COULD ENTER CATALYTIC CONVERTER
AND IGNITE AFTER
THE
ENGINE
IS
STARTED.
THIS COULD CAUSE
THE
CONVERTER
TO
OVER­ HEAT AND RUPTURE.

BOOSTER BATTERY

WARNING:
TO
PREVENT PERSONAL INJURY
OR,
DO
NOT
ALLOW BATTERY ACID
TO
CONTACT

EYES,
SKIN
OR
CLOTHING.
DO NOT
LEAN OVER
A

BATTERY WHEN CONNECTING JUMPER
CABLES.

DO
NOT
ALLOW
THE
POSITIVE
AND
NEGATIVE

CABLE
CLAMPS
TO
CONTACT EACH OTHER.
KEEP
OPEN FLAMES
AND
SPARKS
AWAY FROM
THE BATTERY ELECTROLYTE VENT HOLES.
AL­
WAYS
WEAR
EYE
PROTECTION WHEN INVOLVED

WITH
VEHICLE BATTERIES.

If it becomes necessary to use a booster battery and
jumper cables to start an engine, use the following procedure.
J9200-86

(1) Engage the parking brake. Shift the automatic
transmission to PARK (if a manual transmission, shift to NEUTRAL).
(2) Turn off all lights, and all other electrical

loads.

(3)
Observe the battery condition indicator (Fig. 5).
If the battery condition indicator is light/bright col­
ored (or yellow), replace the battery. Do not attempt
to jump start an engine when the condition indi­
cator is light/bright colored (or yellow). If the
condition indicator is dark in the center (but without a green dot), proceed with connecting the jumper ca­

bles.

WARNING:
THE
ELECTROLYTE (ACID)
IN A
DIS­
CHARGED
BATTERY
CAN
FREEZE.
DO NOT AT­

TEMPT
TO
JUMP START
AN
ENGINE BEFORE DETERMINING
THE
CONDITION
OF THE
BATTERY
ELECTROLYTE.
THE
BATTERY COULD EXPLODE
AND CAUSE SEVERE PERSONAL INJURY.
CAUTION:
Do not
permit
the
metal
surfaces
on the

vehicles
to
contact.
This
could
establish
ground

(negative)
continuity
between
the
vehicle
bodies.

This
could
cause
the
on-board
computers
to be

damaged.
In
addition
it
could
reduce
the
amount
of

current
flow
through
the
starter
motor.

0 - 14
LUBRICATION
AND
MAINTENANCE

•
ENGINE
MAINTENANCE

INDEX

page
Air
Injection
Systems/Air Pump
. 17

Air-Conditioner
Compressor
21
Battery
19

Cooling System
15

Crankcase
Ventilation
System
17
Diesel Engine
Air Filter
Canister
17

Drive Belts
20
Engine
Air
Cleaner
Filter
Element
16

Engine Break-In
14

Engine
Oil 14

Engine
Oil
Change
and Filter
Replacement
15

Exhaust Gas
Recirculation
(EGR) System
...... 19
page
Exhaust
Manifold
Heat
Control
Valve
. 17
Exhaust System
, 21

Fuel System
18

Hoses
and
Fittings
16
Ignition
Cables,
Distributor
Cap and
Rotor
...... 19

Ignition
Timing
. 19

Oxygen
(02)
Sensor
19
Rubber/Plastic Components
20

Spark Plugs
. 19

Throttle
Control
Linkage
18

Vacuum Operated, Emission
Control
Components
19

ENGINE BREAK-IN
After first starting a new engine, allow it to idle
for 15 seconds before shifting into a drive gear. Also:
• Drive the vehicle at varying speeds less than 88
km/h (55 mph) for the first 480 km (300 miles).
• Avoid fast acceleration and sudden stops.
• Do not drive at full-throttle for extended periods of
time
• Do not drive at constant speeds
• Do not idle the engine excessively A special break-in engine oil is not required. The
original engine oil installed is a high quality lubri­
cant. New engines tend to consume more fuel and oil un­
til after the break-in period has ended.

ENGINE
OIL SPECIFICATIONS

API SERWICE
GRADE
Use an engine oil that conforms to API Service
Grade S5 SG/CD or SG/CE. MOPAR®provides engine
oils that conform to all of these service grades.

SULFATED ASH—DIESEL ENGINES
Oils that contain an excessive amount of sulfated
ash can cause deposits to develop on Diesel engine
valves. These deposits can result in valve wear.

SAE
WISC0SITY
An SAE viscosity grade is used to specify the vis­
cosity of engine oil. SAE 30 specifies a single viscos­
ity engine oil.
Engine oils also have multiple viscosities. 10W-30

<
5W-30

1
1 1

F
-20 0 10 20 32 60 80 100

C
-29 -18 -12 -7 0 16 27 38
ANTICIPATED
TEMPERATURE RANGE BEFORE
NEXT
OIL
CHANGE
J9000-39

Fig.
1 Temperature/Engine Oil Viscosity—Gasoline
Engines

-12°C
-18°C 10°F
0°F- 15W-40

-23°c(^-10eF

I
10W-30
WITH
WITHOUT
BLOCK HEATER
BLOCK
SYNTHETIC
OIL

HEATER
10W-30 5W-30

J9100-29

Fig.
2 Temperature/Engine Oil Viscosity—Diesel
Engines

ENERGY
G0NSERWING
OIL
An Energy Conserving type oil is recommended for
gasoline engines. They are designated as either EN­
ERGY CONSERVING or ENERGY CONSERVING

II.
OIL
LEVEL
INDICATOR (DIPSTICK)

GASOLINE ENGINES
The engine oil indicator is located at the right
front of the engine.

•

LUBRICATION
AND
MAINTENANCE
0 - 15
DIESEL
ENGINES

The Diesel engine oil level indicator is located at
the left center of the engine, above the
fuel
injection

pump (Fig. 3).

Fig.
3
Diesel
Engine
Oil
Dipstick

ACCEPTABLE
OIL
LEVEL
To maintain proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
For gasoline engines, the acceptable levels are indi­ cated between the ADD and
FULL
marks on oil
dip­
stick. For Diesel engines, the acceptable levels are
indicated between the L (low) and H
(high) marks
on
oil dipstick. The oil level should be checked periodically. The
vehicle should be on a level surface. Wait for
five
minutes after stopping the engine. For gasoline en­
gines,
add oil only when the level indicated on the
dipstick is at or below the ADD mark. For Diesel en­
gines,
add oil only when the level indicated on the
dipstick is between the L and H marks.
Never oper­
ate a Diesel
engine when
the oil
level
is below
the L mark. The distance between the L and H
marks represents 1.9L (2 Qts) engine oil.

CAUTION:
Do not
overfill
an
engine crankcase
with

oil. This
will
cause
oil
aeration
and
result
in a de­

crease
in the
engine
oil
pressure.
ENGINE
OIL
CHANGE AND FILTER REPLACEMENT

WARNING: PROTECTIVE CLOTHING
AND
GLOVES SHOULD
BE
WORN. EXPOSED SKIN SHOULD
BE

WASHED
WITH
SOAP
AND
WATER
TO
REMOVE
USED
ENGINE
OIL.
DO NOT
USE
GASOLINE, THIN­
NER,
OR
SOLVENTS
TO
REMOVE ENGINE
OIL

FROM
SKIN.
DO NOT
POLLUTE. DISPOSE
OF
USED
ENGINE
OIL
PROPERLY.
ENGINE
OIL
FILTER

All engines are equipped with a throw-away type
oil filter. The same type of filter is recommended
when the filter is changed.

OIL CHANGE
AND
FILTER
REPLACEMENT
Bring engine up to normal operating temperature.
A more complete drainage of oil will result.
(1) Remove the drain hole plug and drain the en­
gine oil from the crankcase.
(2) Install the drain hole plug with a replacement
gasket. For gasoline engines, the oil filter should be
replaced during every second engine oil change.
For Diesel engines, the oil filter should be re­
placed during every engine oil change.
(3) Rotate the oil filter counterclockwise to remove
it.
(4) Clean the engine cylinder block oil filter boss. (5) Apply a light coat of new engine oil to the rub­
ber seal on the oil filter.
(6) Install and hand tighten the oil filter 1/2 to 3/4
of a turn clockwise. (7) Add new engine oil at the fill hole location on
top of the engine cylinder head cover. Wipe off any spilled oil.
(8) Observe the oil level on the dipstick.

CAUTION:
Do not
overfill
the
engine crankcase
with

oil.
(9)
Start the engine. Observe the oil pressure
gauge or warning lamp (as applicable). If the oil
pressure does not increase, stop the engine immedi­ ately. Check oil level.

COOLING SYSTEM

WARNING:
USE
EXTREME CAUTION WHEN
THE
ENGINE
IS
OPERATING.
DO NOT PUT
YOUR
HANDS NEAR
THE
DRIVE BELT(S), PULLEYS
OR
FAN BLADE.
DO NOT
STAND
IN A
DIRECT LINE
WITH
THE FAN
BLADE.

INSPECTION SCHEDULE
Determine the coolant level. Inspect the cooling
system hoses/clamps after each service interval has
elapsed.

COOLANT LEVEL
It is recommended that the engine coolant level be
inspected at least once a month during periods of hot
weather.
With the engine at normal operating temperature,
check the coolant level in the coolant reserve tank.
The coolant level must be at least above the ADD mark. Add coolant to the coolant reserve tank only.

0-18
LUBRICATION
AND
MAINTENANCE

• MAINTENANCE SCHEDULE
A crankcase ventilation system must be clean to
provide good operation and durability. Periodic main­
tenance is necessary. Replace the PCV valve. Re­
move residual combustion deposits from the hoses and throttle body/intake manifold passages.
The PCV valve should be replaced and the system
should be serviced at the interval specified in main­
tenance schedule. If a vehicle is routinely used for short trips, the crankcase ventilation system could
possibly require more maintenance.
CRANKCASE AIR INLET FILTER
MAINTENANCE SCHEDULE Replace or clean, the air inlet filter at the interval
specified in maintenance schedule.
More frequent PCV system maintenance could be
required for:
• Vehicles routinely used for short trips
• Vehicles routinely involved in stop and go traffic
operation
• Vehicles routinely involved in extended periods of
engine idle
MAINTENANCE Clean and lubricate the crankcase air inlet filter
according to the following procedure. (1) Disconnect the fresh air hose from the port on
the crankcase air inlet filter housing (Fig. 8).
(2) Remove the air filter housing from the cylinder
head cover (Fig. 8). Clean the filter in kerosene or a similar solvent.
(3) Lubricate the filter by inverting the housing
and filling it with SAE 30 viscosity engine oil.
(4) Insert the air filter housing nipple in the cylin­
der head cover grommet. Connect the fresh air hose
to the upper port (Fig. 8).
J9000-52

Fig.
8
Crankcase
Air Inlet
Filter
THROTTLE CONTROL LINKAGE

Transmission linkage pivot pin areas (Fig. 9),
should be serviced. The areas lubricated every second
oil change with a multi-purpose lubricant (NLGI GC-
LB).

PIVOT
AREAS
Fig.
9
Transmission
Linkage
Pivot Areas

FUEL
SYSTEM

INSPECTION The fuel system filler cap, nozzle, tubes, hoses, and
connections should be inspected periodically.
FUEL FILTER The fuel filter requires service only when a fuel
contamination problem is suspected. For proper diag­
nosis and service procedures refer to Group 14, Fuel
System.
GASOLINE ENGINE FUEL REQUIREMENTS All gasoline engines require fuel that has a mini­
mum octane rating of 87 determined by the (R +
M)/2 calculation method.
The use of a brand of unleaded gasoline that con­
tains additives is recommended. Gasoline with addi­
tives will improve fuel economy and reduce emissions.

ALCOHOL/GASOLINE
BLENDS
Many brands of blended unleaded gasoline am now
available. Unleaded gasoline is blended with oxygenated-type
fuels to produce a clean air gasoline in many areas.
The use of this type of blended fuel is recommended.
ETH ANOL—Unleaded gasoline and ethanol
blended fuels are a mixture of 10 percent ethanol and 90 percent unleaded gasoline. This is an accept­
able blend of fuel.
MTBE— MTBE blended fuels are a mixture of un­
leaded gasoline and up to 15 percent MTBE (Methyl
Tertiary Butyl Ether). Unleaded gasoline blended
with MTBE is acceptable.

•

IGNITION
SYSTEMS
8D - 15 J908D-15

Fig.
22 Normal Operation and Cold (Carbon) Fouling
sically carbon (Fig. 22). A dry, black deposit on one
or two plugs in a set may be caused by sticking
valves or defective spark plug cables. Cold (carbon)
fouling of the entire set of spark plugs may be caused
by a clogged air filter or .repeated short operating
times (short trips).

ELECTRODE GAP BRIDGIMG
Electrode gap bridging may be traced to loose de­
posits in the combustion chamber. These deposits ac­ cumulate on the spark plugs during continuous stop-
and-go driving. When the engine is suddenly
subjected to a high torque load, deposits partially liq­
uefy and bridge the gap between electrodes (Fig. 28).
This short circuits the electrodes. Spark plugs with electrode gap bridging can be cleaned using standard
procedures.

GROUND
ELECTRODE

J908D-11
Fig. 23 Electrode Gap Bridging

SCAVENGER
DEPOSITS
Fuel scavenger deposits may be either white or yel­
low (Fig. 24). They may appear to be harmful, but
this is a normal condition caused by chemical addi­
tives in certain fuels. These additives are designed to change the chemical nature of deposits and decrease
spark plug misfire tendencies. Notice that accumula­
tion on the ground electrode and shell area may be
heavy, but the deposits are easily removed. Spark
plugs with scavenger deposits can be considered nor­ mal in condition and can be cleaned using standard
procedures.

GROUND
ELECTRODE
COVERED

J908D-12

Fig.
24
Scavenger
Deposits

CHIPPED ELECTRODE
INSULATOR
A chipped electrode insulator usually results from
bending the center electrode while adjusting the spark plug electrode gap. Under certain conditions, severe detonation can also separate the insulator
from the center electrode (Fig. 25). Spark plugs with
this condition must be replaced.
GROUND

J908D-13

Fig.
25
Chipped
Electrode Insulator
PREIGNITION
DAMAGE

Preignition damage is usually caused by excessive
combustion chamber temperature. The center elec­
trode dissolves first and the ground electrode dis­ solves somewhat latter (Fig. 26). Insulators appear
relatively deposit free. Determine if the spark plug
has the correct heat range rating for the engine. De­
termine if ignition timing is over advanced, or if

8E
- 4
INSTRUMENT PANEL
AND
GAUGES

•
MESSAGE CENTER—DIESEL
ENGINE

The message center (Fig. 7), which
is
located above
the Heater-A/C controls, includes warning lamps
for

the:

• brake systems (parking
and
service brakes)
• ABS brakes
• water
in
fuel
• wait
to
start (controlled
by Air
Heater Control
Module)
• Low Fuel.

BRAKE

CUMMINS
TURBO
DIESEL,

LOW
FUEL

DIESEL
FUEL ONLY WATER
IN
FUEL
WAIT
TO
START
J938E-55

Fig.
7
Message Center—Diesel Engine

ABS
WARNING LIGHT
This light monitors
the
ABS Brake System. This
light will come
on
when the ignition key
is
turned
to

the
ON
position
and may
stay
on for as
long
as

thirty seconds.
If
the ABS light remains
on or
comes
on during driving,
it
indicates that
the
ABS portion
of
the
brake system
is not
functioning. Refer
to
Group
5 -
Brakes
for
further information.
BRAKE
SYSTEM WARNING LIGHT

The Brake light
is
connected
to a
sensor that mon­
itors vacuum
in
the brake booster system. The Brake
light when
lit
indicates LOW VACUUM. The dual brake system provides
a
reserve braking
capability
in
the event
of a
failure
to a
portion
of
the
hydraulic system. Failure
of
either
of the
dual sys­
tem
is
indicated
by the
brake warning light which
will glow when
the
service brake pedal
is
depressed.
The light will remain
on
until
the
cause
is
corrected. The light will also come
on
when
the
parking
brake
is
applied with the ignition
in
the ON position. Refer
to
Group
5 -
Brakes
for
further information.

WATER
IN
FUEL
The Water
In
Fuel light
is
connected
to a
sensor lo­
cated
in the
fuel filter.
If
water collects
in the
fuel/
water separator filter,
the
Water
In
Fuel indicator
will light.

WAIT
TO
START
The Wait
To
Start light
is
connected
to a
sensor
that monitors intake
air
temperature
in the
intake
manifold.
If
intake
air
temperature
is low and
igni­
tion switch
is in
ON position,
the
PCM sends current
to
the
intake manifold
air
heaters
and the
Wait
To
Start light. This intake manifold preheat cycle
is

controlled
by an
electronic
Air
Heater Control Mod­

ule.
LOW FUEL
The Low Fuel light
is
connected
to a
sensor
in the

fuel tank. When the fuel level reaches approximately 1/6
of a
tank,
the
words LOW FUEL will illuminate
and remain
on
until fuel
is
added.

8W - 66 WIRING DIAGRAMS
•
WATER-1N-FUEL
SENSOR
(IN FUEL FILTER)
VEHICLE

SPEED SENSOR
(ON REAR
OF TRANSMISSION
MANUAL TRANSMISSION AND 205

TRANSFER
CASE
CRANKSHAFT POSITION

SENSOR

FRONT OF
ENGINE) INTAKE AIR

TEMPERATURE
SENSOR

IN INTAKE
LEFT SIDE)
TO LEFT
PRINTED CIRCUIT

BOARD
CONNECTOR
[SEE
SH 60)
TO DAYTIME
RUNNING
LIGHT
MODULE
(CANADA ONLY)

(SEE
SH 46)
47 7 2 1 21 24
28
VEHICLE 8 VOLT ECT WATER -1N- INTAKE
CKP

THERMO

SPEED SENSOR
INPUT
SENSOR

FUEL AIR TEMP PICK-UP
SWITCH
PICK-UP
SENSOR

CONNECTOR
POWERTRAIN CONTROL MODULE II (PCM II)
(SEE
SH 83)

(LEFT
FENDER SIDE SHIELD)
AD 25
DIESEL
CONTROL SYSTEM
J938H-11

9
- 2
ENGINES

rial surrounds each mounting hole. Excess material
can easily be wiped off. Components should be
torqued in place within 15 minutes. The use of a lo­ cating dowel is recommended during assembly to pre­
vent smearing the material off location.

ENGINE PERFORMANCE
To provide best vehicle performance and lowest ve­
hicle emissions, it is most important that the tune-up
be done accurately. Use the specifications listed on
the Vehicle Emission Control Information label found on the engine compartment hood.
(1) Test cranking amperage draw (refer to Group

8B,
Battery/Starter/Generator Service for the proper
procedures).
(2) Tighten the intake manifold bolts (refer to
Group 11, Exhaust System and Intake Manifold for
the proper specifications). (3) Perform cylinder compression test:
(a) Check engine oil level and add oil, if neces­
sary.
(b) Drive the vehicle until engine reaches normal
operating temperature. (c) Select a route free from traffic and other
forms of congestion, observe all traffic laws and
briskly accelerate through the gears several times. The higher engine speed may help clean out valve seat deposits which can prevent accurate compres­
sion readings.

CAUTION:
DO NOT
overspeed
the
engine.
(d) Remove all spark plugs from engine. As
spark plugs are being removed, check electrodes for
abnormal firing indicators - fouled, hot, oily, etc.
Record cylinder number of spark plug for future
reference.
(e) Disconnect coil wire from distributor and se­
cure to good ground to prevent a spark from start­
ing a fire.
(f) Be sure throttle blades are fully open during
the compression check. (g) Insert compression gage adaptor into the
No.l spark plug hole. Crank engine until maxi­
mum pressure is reached on gauge. Record this
pressure as No.l cylinder pressure.
(h) Repeat Step 3g for all remaining cylinders.
(i) Compression should not be less than 689 kPa
(100 psi) and not vary more than 172 kPa (25 psi)
from cylinder to cylinder.
(j) If cylinder(s) have abnormally low compres­
sion pressures, repeat steps 3a through 3h. (k) If the same cylinder(s) repeat an abnormally
low reading, it could indicate the existence of a
problem in the cylinder.
The recommended compression pressures are
to be used only as a guide to diagnosing engine
problems. An engine should NOT be disassem­ bled to determine the cause of low compression
unless some malfunction is present. (4) Clean or replace spark plugs as necessary. Ad­
just gap (refer to Group 8D, Ignition System for gap adjustment and torque).
(5) Test resistance of spark plug cables (refer to
Group 8D, Ignition System.
(6) Inspect the primary wire. Test coil output volt­

age,
primary and secondary resistance. Replace parts as necessary (refer to Group 8D, Ignition System and
make necessary adjustment).
(7) Set ignition timing to specifications (refer to
Specification Label on engine compartment hood).
(8) Perform a combustion analysis.
(9) Test fuel pump for pressure and vacuum (refer
to Group 14, Fuel System for the proper specifica­

tions).

(10) Inspect air filter element (refer to Group 0,
Lubrication and Maintenance for the proper proce­
dure).

(11) Inspect crankcase ventilation system (refer to
Group 0, Lubrication and Maintenance for the proper
procedure).
(12) For emission controls refer to Group 25, Emis­
sion Controls System for service procedures.
(13) Inspect and adjust accessory belt drives (refer
to Group 7, Cooling System for the proper adjust­
ments).

(14) Road test vehicle as a final test.

H0NIN6
CYLINDER
BORES
Before honing, stuff plenty of clean shop towels un­
der the bores and over the crankshaft to keep abra­ sive materials from entering the crankshaft area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823 equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round as well as removing light scuffing, scoring or scratches. Usually a few strokes
will clean up a bore and maintain the required lim­
its.

CAUTION:
DO NOT use rigid type
hones
to remove

cylinder
wall
glaze.

(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin­
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). 20-60 strokes, de­
pending on the bore condition, will be sufficient to
provide a satisfactory surface. Using honing oil C-3501-3880 or a light honing oil available from ma­
jor oil distributors.

CAUTION:
DO NOT use engine or
transmission
oil, mineral
spirits
or
kerosene.