oil DODGE TRUCK 1993 Service Manual PDF

CLUTCH
6 - 7
CLUTCH
SLIPS

Condition
Found
Cause
Correction

1.
Disc
facing
worn
out. a) Normal wear.
b) Driver
frequently
"rides"
(slips)
clutch. Results in rapid
wear overheating.
c) Insufficient clutch cover diaphragm spring tension. Replace clutch
disc.
Also
replace
cover if spring is weak or pressure
plate
surface is damaged.
2. Clutch disc facing contaminated
with
oil, grease,
or clutch fluid. a) Leak at
rear
main seal or at

transmission
input shaft seal.
b) Excessive amount of grease applied to input shaft splines.
c) Road
splash,
water
entering
housing.

d) Slave cylinder leaking. a), b), c), d) Replace leaking

seals.
Apply
less
grease to
input shaft splines. Replace
clutch disc (do not clean and reuse). Clean clutch cover and
reuse only if cover is in good
condition. Replace slave
cylinder if leaking.
3. Clutch is running
partially
disengaged.
Release
bearing sticking-binding.

Does
not
return
to normal running

position.
Verify
that
bearing is actually

binding,
then
replace bearing and

transmission
front
bearing
retainer
if sleeve surface is damaged.
4. Flywheel height incorrect. Flywheel surface improperly
machined. Too much stock removed
or surface is tapered. Replace flywheel.
5. Wrong disc or pressure
plate
installed. Incorrect parts order or model
number. Replace
with
correct parts.
Compare old and new parts before installation.
6. Clutch
disc,
cover and/or diaphragm spring, warped,
distorted. a)
Rough
handling (impact) bent
cover, spring, or
disc.

b) Incorrect bolt tightening sequence and method caused
warped cover. Install new disc or cover as needed.
Follow installation/tightening
instructions.
7. Facing on
flywheel
side of disc torn,
gouged,
worn. Flywheel surface scored and nicked.

Reduce
scores and nicks by sanding
or surface grinding. Replace

flywheel
if scores-nicks are deeper
than
.002-.004
inch.
8. Clutch disc facing burnt (charred). Flywheel and cover
pressure
plate
surfaces heavily

glazed.
a) Frequent operation under high

loads
or hard acceleration

conditions.

b) Driver
frequently
"rides"
(slips)
clutch. Results in rapid
wear and overheating of disc and cover.
Scuff
sand flywheel. Replace clutch
cover and
disc.
Alert driver to problem cause.
J9006-21

•

CLUTCH
6 - 9 CLUTCH GRAB/CHATTER
Condition
Found
Cause
T

Correction

1.
Clutch
disc
facing covered
with

oil, grease, or clutch fluid. a) Oil leak at
rear
main or input
shaft seal.
b) Too much grease applied to
splines
or
disc
and input shaft. a) Correct leak and replace
disc

(do not clean and reuse the

disc).

b) Apply lighter grease coating to splines and replace
disc
(do not clean and reuse the disc).
2. Clutch
disc
and/or cover warped, or
disc
facings
exhibit
unusual
wear or appear to be
wrong type. Incorrect or substandard parts.
Replace
disc
and/or cover
with

correct parts.
3. Clutch master or slave cylinder plunger dragging-binding. a) Master or slave cylinder
components worn or corroded. a) Replace both cylinders as

assembly
(and reservoir).
4. No
fault
found
with
clutch
components.
a) Problem actually
related
to

suspension
or driveline
component.
b) Engine
related
problem. a)
Further
diagnosis
required.

Check
engine/transmission
mounts,
propeller shafts and U-joints, tires,
suspension

attaching parts and other
driveline components as needed.
b) Check EFI and igniton
systems.

5.
Partial
engagement of clutch
disc
(one side worn-opposite

side
glazed and lightly worn). a) Clutch pressure
plate
position
setting incorrect or modified.
b) Clutch cover, spring, or release fingers bent, distorted (rough
handling,
improper assembly).
c) Clutch
disc
damaged or distorted.
d) Clutch misalignment. a) Replace clutch cover and
disc.

b) Replace clutch cover and
disc.

c) Replace
disc.

d) Check alignment and runout of flywheel,
disc,
or cover and/or clutch
housing.
Correct as
necessary.
J9006-23

7 - 2
COOLING
SYSTEM

•

NOTE: HEATER
COOLANT FLOW
CIRCUIT
IS
ALWAYS

OPEN
EXCEPT
WHEN
IN MAX. A/C
OR
OFF
MODES
HEATER
INTAKE MANIFOLD
COOLANT FLOW "METERED" FROM REAR
TO

FRONT
AND
BELOW EXHAUST HEAT
CROSSOVER
SHUT
OFF
VALVE

A/C
ONLY COOLANT FLOW
-
PUMP
TO

CYLINDER
BLOCK,
UP
THROUGH
CYLINDER
HEADS
TO
INTAKE MANIFOLD WATER BOX
TO
RADIATOR
—
TO PUMP

•BYPASS
THERMOSTAT CLOSED-HIGH FLOW
THERMOSTAT OPEN
-
LOW FLOW

CYLINDER
HEAD
RR07B52

Fig.
2
Cooling
System
Routing—5.9L (V-8 Gas)—Typical All vehicles are equipped with either a 3.9L (V-6),
a 5.2L (V-8), a 5.9L (LDC-gas V-8), a 5.9L (HDC-gas
V-8) or a 5.9L (in-line 6 cylinder diesel) engine.
As coolant temperature reaches approximately

220°F,
the engine idle speed is increased by the pow-
ertrain control module (PCM) to provide increased
cooling system performance. The PCM was formerly
referred to as the engine controller or SBEC.

COOLING
SYSTEM
COMPONENTS—EXCEPT

DIESEL
ENGINE
The cooling system consists of:
• A down-flow radiator
• Thermal viscous fan drive
• Fan shroud
• Radiator pressure cap
• Thermostat
• Coolant reserve/overflow system
• Transmission oil cooler (automatic transmission)
• Coolant
• Water pump (to circulate coolant)
• Hoses and hose clamps Coolant flow circuits for 3.9L (V-6) and 5.2L (V-8)
engines with water cooled intake manifolds are
shown in figure 1. Coolant flow circuits for 5.9L (V-8 Gas) engines
with water cooled intake manifolds are shown in fig­ ure 2.
COOLING
SYSTEM
COMPONENTS-DIESEL

ENGINE
Coolant flow circuits for 5.9L (diesel) engines with
water cooled intake manifolds are shown in figure 3. The cooling system (Fig. 3) consists of: a cross-flow
radiator, engine driven cooling fan, thermal viscous
fan drive, fan shroud, radiator pressure cap, thermo­ stat, coolant reserve/overflow system, transmission
oil cooler (if equipped with an automatic transmis­
sion),
coolant, water pump, hoses and hose clamps.

SYSTEM
COOLANT ROUTING-DIESEL ENGINE
Coolant is drawn from radiator into the water
pump. Water pump output is directed to the engine oil cooler cavity of the cylinder block (Fig. 4). From the oil cooler cavity, the coolant circulates
around each cylinder. It then crosses to the lift pump
side of engine where it flows up into cylinder head
through openings in top of cylinder block (Fig. 4). Coolant flows past the valve bridges (Fig. 5), to ex­
haust manifold side of engine, to thermostat. As cool­ ant flows toward the thermostat, it provides cooling
for the injector nozzle.
When thermostat is closed (engine is below operating
temperature), coolant flows through bypass passage to
water pump inlet (Fig. 6). Once operating temperature is reached, the thermostat opens and blocks the bypass
passage. Coolant then flows to the radiator inlet.

•
COOLING
SYSTEM
7 - 6 COOLING SYSTEM DIAGNOSIS (EXCEPT DIESEL)

CONDITION
AND
CHICK

OPTIONAL
M°¥
GAUGE
READS
LOW
(!) Verify
gauge
reading. Is a low temperature indicated?
(2) Is code 17 recorded in On Board
Diagnostics
memory?
(3) Is the
gauge
reading in the cold
range?

(4) Low coolant level during cold ambient temperatures
(accompanied
with poor heater performance).
(5) Coolant level is correct.

GAUGE
HEADING
HIGH.
NO
PRESSURE
BLOW
OFF
FROM
RADIATOR
PRESSURE
CAP
OR
STEAM
FROM
COOLANT

RESERVE
TANK.

(1) Verify
gauge
reading. Is a high temperature reading indicated?
(2)
Gauge
reading at
"H"
without
signs
of boiling.
(3) Low coolant level in radiator and coolant reserve tank.
(4) Coolant level in radiator is low. But not low in coolant reserve tank.
(5) Test coolant
freeze
point.
(6) Ensure proper coolant flow.
DIAGNOSIS

30° TO 40°

GAUGE
TRAVEL
IS
NORMAL

Normal
Gauge
Travel
(1) Inspect temperature
gauge
sending
unit. Refer to Group 8, Electrical. Repair or replace sending unit as necessary.
(2) If code 17 is recorded, replace the thermostat. If not, the thermostat is not the
cause
of the low
gauge
reading.
(3) Inspect for
disconnected
sending
unit electrical connector or incorrect
sending
unit. Ensure that
gauge
sending
unit is installed

and
not an indicator light switch.
(4)
WARNING:
DO NOT
REMOVE
THE
RADIATOR
CAP
OF A
HOT,
PRESSURIZED
ENGINE.
SERIOUS
INJURY
CAN

RESULT
FROM
SCALDING
COOLANT.

Inspect
coolant level in the coolant reserve tank and radiator.

Inspect
system
for leaks.
(5) Inspect heater door
controls.
Refer to Group 24, Heating and
Air
Conditioning.

TO
TOP
AMBIENT

High
Gauge
Reading
— Hot Weather — Heavy Load
(1) Compare
gauge
reading to
High
Gauge
Reading Illustration
above.

(2) Inspect for grounded
gauge,
sending
unit or circuit. Refer to
Group
8, Electrical.
(3) a — Pill to full.
b
— Inspect for leaks in
system
and repair as
necessary,

c
—
Ensure
radiator pressure cap was shut tight. Verify
proper
operation of the radiator cap upper and lower
seals.

(4) a —
Fill
to full,
b
— Inspect for leaks in the
system
and repair as
necessary,

c
— Inspect for leaks in the coolant reserve tank to radiator
hose.

d
— Verify proper operation of the radiator cap upper and lower
seals.

(5) a — Adjust coolant solution to
50/50
mixture of anti-freeze and water. Refer to Coolant in this
group,

b
— If a reading is not recorded or below
—
50, the mixture is
too
rich. Clean
system
and
fill
with a
50/50
mixture of
anti-freeze and water. Refer to Coolant in this
group.

(6) a •— With the thermostat open and a slight amount of coolant
removed,
inspect for coolant flow through the radiator at
the
filler
neck opening,

b
— Determine reason for lack of coolant flow and repair as
necessary.
J9007-69

•

COOLING
SYSTEM
7 - 7 COOLING SYSTEM DIAGNOSIS (EXCEPT DIESELJ-GONTINUED

CONDITION
AND
CHECKS
DIAGNOSIS

TEMPERATURE
GAUGE
IS
INCONSISTENT,
CYCLES
AND/OR
IS
ERRATIC.

(1) Is cycle normal.
MID

(a)
Normal Gauge Reaction to Thermostat Cycle.

MID

(b) Normal Gauge Reaction at Stop After Heavy Use.
(c) Hot Water Build-Up is Normal at
Stop
after
Heavy Use.
(2)
Is
coolant in radiator low (air
will
build up in the cooling
system
(2)
Fill
system,
vent trapped air and check for leaks,
and
cause
the thermostat to open
late).

(3)
Is
a cylinder head gasket leak allowing exhaust
gas
to
enter
(3) a — Test for leaking cylinder head
gasket
leak
with
a
cooling
system
(exhaust
gas
building up in the cooling
system
will
commercially available Block Leak Tester,

cause
the thermostat to open
late).

b
— Check for coolant in engine oil.

c
— Inspect for
white
steam from exhaust
system.

(4)
Water pump impeller loose on shaft.
Loose
accessory
drive belt. (4) Repair or replace as necessary.

(5)
Air leak
on
the
suction
side of the
water
pump (allows air to build (5) Find leak and repair,
up
in cooling
system
causing
thermostat to open
late).

WARNING
LIGHT
GLOWS
ALL
THE
TIME
(VEHICLE
NOT
EQUIPPED
WITH
GAUGE).

(1) Inspect
temperature
gauge
sending
unit. The warning light
sending
(1)
Ensure
that
a warning light
sending
unit
is
installed, unit
has
a screwdriver slot in the electrode (used for calibration).

Gauge
sending
units do not have a slot in the electrode.

NO
GAUGE
READING
INITIALLY
THEN
HOT
INDICATION

(VEHICLE
EQUIPPED
WITH
GAUGE).

(1)
Gauge
stationary
until
very hot, then
moves
immediately to "H"
(1)
Vehicle
is
equipped
with
sending
unit for light not
gauge.
J9007-70

7-10 COOLING SYSTEM
•
DIESEL
COOLING SYSTEM
DIAGNOSIS

CONDITION AND CHECKS
DIAGNOSIS

OPTIONAL
60»F
GAUGE
READS
LOW 30° TO 40°
GAUGE
TRAVEL
IS
NORMAL
(1)
Verify
gauge reading. Is a low
temperature
indicated?
(2) Thermostat stuck in open position?
(3) Is the gauge reading in the cold range?
(4) Low coolant
level
during cold ambient temperatures (accom­ panied
with
poor
heater
performance).
(5) Coolant
level
is correct.
MID

Normal
Gauge
Travel

(1) Inspect
temperature
gauge sending unit. Refer to Group 8,
Electrical. Repair or replace sending
unit
as necessary.
(2) If
Yes,
replace the thermostat. If not, the thermostat is not the
cause
of the low gauge
reading.

(3) Inspect for disconnected sending
unit
electrical
connector or
incorrect
sending unit. Ensure
that
gauge sending
unit
is in­
stalled and not an indicator light switch.
(4) WARNING: DO NOT REMOVE THE RADIATOR CAP
OF
A HOT, PRESSURIZED ENGINE. SERIOUS IN­
JURY CAN RESULT FROM SCALDING COOLANT. Inspect coolant
level
in the coolant reserve tank and radiator. Inspect system for leaks.
(5) Inspect
heater
door
controls.
Refer to Group 24, Heating and
Air Conditioning.

GAUGE
READING HIGH. NO PRESSURE BLOW OFF FROM RADIATOR PRESSURE CAP OR STEAM FROM
COOLANT
RESERVE
TANK.
X

(1)
Verify
gauge reading. Is a high
temperature
reading indi­
cated?

(2) Gauge reading at "H"
without
signs
of boiling.
(3) Low coolant
level
in radiator and coolant reserve tank.
MAXIMUM
HOT

WEATHER

HEAVY
LOAD

MAXIMUM
UP

TO
TOP AMBIENT High Gauge
Reading
— Hot
Weather
—
Heavy
Load

(1) Compare gauge reading to High Gauge Reading Illustration
above.
(2) Inspect for grounded
gauge,
sending
unit
or circuit. Refer to

Group
8, Electrical.
(4) Coolant
level
in radiator
is
low.
But
not low in coolant reserve tank.
(5) Test coolant
freeze
point. (3) a-
b — (4) a-
b —
d —
(5) a- (6) Ensure proper coolant flow.
(6) a-
b —
Fill
to
full.

Inspect for leaks in system and
repair

as
necessary.
Ensure
radiator pressure cap was shut
tight.
Verify
proper operation of the radiator

cap
upper and lower
seals.
Fill
to
full.

Inspect for leaks in the system and
repair

as
necessary.
Inspect for leaks in the coolant reserve
tank to radiator hose.
Verify
proper operation of the radiator cap
upper and lower
seals.

Adjust coolant solution to
50/50
mixture
of
anti-freeze
and
water.
Refer to Coolant
in this group. If a reading is not recorded or below - 50.
the
mixture
is too rich. Clean system and
fill

with
a
50/50
mixture
of
anti-freeze
and
water.
Refer to Coolant in this group.
With the thermostat open and a slight amount
of coolant removed, inspect for coolant flow
through the radiator at the
filler
neck opening. Determine reason for lack of coolant flow
and
repair
as necessary.
J9107-22

7
- 12
COOLING
SYSTEM

• DIESEL COOLING SYSTEM DIAGNOSIS-CONTINUED

CONDITION
AND
CHECKS
DIAGNOSIS

TEMPERATURE GAUGE
IS
INCONSISTENT,
CYCLES
AND/OR
IS
ERRATIC.
J
(1)
Is
cycle
normal.

(a)
Normal
Gauge
Reaction
to Thermostat
Cycle.
Normal
Gauge
Reaction
to Thermostat
Cycle.

MID

(b)
Normal
Gauge
Reaction
at
Stop
After
Heavy
Use.
(c)
Hot
Water
Build-Up
Is
Normal
at
Stop
after
Heavy

Use.

(2)
Is
coolant
in
radiator
low
(air
will
build
up in
the
cooling
system and cause
the
thermostat
to
open
late). (2)

Fill
system,
vent
trapped
air
and
check
for
leaks.

(3)
Is
a
cylinder
head
gasket
leak
allowing
exhaust
gas
to
enter
cooling
system
(exhaust
gas
building
up in
the

cooling
system
will
cause
the
thermostat
to
open
late).
(3)

a
—
Test
for
leaking
cylinder
gasket
leak
with
a

commercially
available
Block
Leak
Tester,

b
—
Check
for
coolant
in
enaine
oil.

c
—
Inspect
for
white
steam
from
exhaust
system.

(4)
Water
pump
impeller
loose
on
shaft.
Loose
accessory
drive
belt. (4)

Repair or
replace
as
necessary.

(5)
Air
leak
on
the
suction
side
of the
water
pump
(allows
air
to
build
up in
cooling
system causing
thermostat
to
open
late). (5)

Find
leak
and
repair.

PRESSURE
CAP
VENTS
TO
ATMOSPHERE
AND
COOL­

ANT
RESERVE
TANK.
TEMPERATURE GAUGE
READ­

ING ABOVE NORMAL
BUT NOT
HIGH.

(1)
Test
radiator
pressure
cap
relief
pressure.
Refer
to
Radiator
Pressure
cap
section
in
this
group.
ID

Replace
cap
if relief
pressure
is
lower
than
14
psi.
COOLANT
LOSS
VISIBLE
ON
GROUND BELOW VEHI­

CLE,
BUT NO
PRESSURE
CAP
BLOW
OFF.

(1)
Inspect
system
for
leaks.
(1)
Repair
as
necessary.
J9107-23

•

COOLING SYSTEM
7 - 15
SERVICE
PROCEDURES

INDEX
page
Coolant
26
Coolant Reserve/Overflow System
30

Cooling System Cleaning/Reverse Flushing
28

Cooling System Fan—Diesel Engine
. 37

Cooling System
Fan—Gas
Engines
36

Cooling System
Hoses
34
Draining Cooling System
27

Pressure
Testing
Radiator
Caps
............. 32

Radiator Pressure
Cap 31

Radiators
32

Refilling
the
Cooling System
28

WATER PUMPS—EXCEPT DIESEL
A centrifugal water pump circulates coolant
through the water jackets, passages, intake manifold,
radiator core, cooling system hoses and heater core.
The pump is driven from the engine crankshaft by a drive belt. The water pump impeller is pressed onto the rear
of a shaft that rotates in a bearing pressed into the
water pump body. The body has a small hole for ven­
tilation. The water pump seals are lubricated by an­
tifreeze in the coolant mixture. Additional lubrication is not necessary. A quick test to determine if pump is working is to
check if heater warms properly. A defective water
pump will not be able to circulate heated coolant
through the long heater hose to the heater core. The water pump on all models can be removed
without discharging the air conditioning system (if equipped).
REMOVAL The water pump on all gas powered engines is
bolted directly to the engine timing chain case/cover.
A gasket is used as a seal between the water pump
and timing chain case/cover.
If water pump is replaced because of bearing/shaft
damage or leaking shaft seal, the mechanical cooling
fan assembly should also be inspected. Inspect for fa­ tigue cracks, loose blades or loose rivets that could
have resulted from excessive vibration. Replace fan if any of these conditions are found. Also check condi­
tion of the thermal viscous fan drive. Refer to Vis­
cous Fan Drive in this group. (1) Disconnect negative battery cable from battery.
(2) Drain cooling system. Refer to Draining Cool­
ing System in this group. Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
(3)
Disconnect throttle cable from clip at top of fan
shroud.
page

Testing
Cooling System
for
Leaks
. 29

Thermostat
22

Transmission
Oil
Cooler—Diesel
35

Transmission
Oil
Cooler—Except Diesel
35

Transmission Oil-To-Air Cooler
36
Viscous
Fan
Drive
38

Water
Pump
Bypass
Hose—All
Gas
Powered
Engines
.............................. 19

Water
Pumps—5.9L Diesel
18

Water
Pumps—Except Diesel
15
(4) Unsnap coolant reserve/overflow tank (up and
out) from the T-slots on side of fan shroud (Fig. 1) and lay aside. Do not disconnect hose or drain cool­
ant from tank.
(5) Remove the fan shroud from the radiator. Do
not remove shroud from vehicle at this time.
FAN

SHROUD
J9107-67

Fig.
1 Fan
Shroud—Except
Diesel

(6) Remove upper radiator hose at radiator. Special
Clamp Tool number 6094 (Fig. 2) may be used to re­
move the constant tension clamps.
(7) The thermal viscous fan drive is attached
(threaded) to the water pump hub shaft (Fig. 3). Re­
move the fan/fan drive assembly from water pump by
turning the mounting nut counterclockwise (as viewed from front). Threads on the fan drive are RIGHT HAND. A Snap-On 36 MM Fan Wrench (number SP346 from Snap-On Cummins Diesel Tool
Set number 2017DSP) can be used. Place a bar or
screwdriver between the water pump pulley bolts (Fig. 3) to prevent the pulley from rotating.
If water pump is being replaced, do not unbolt fan
blade assembly (Fig. 3) from the thermal control fan drive.

7 - 20
COOLING
SYSTEM

•

HOSE
CLAMP
HOSE

J9207-36
Fig.
16
Hose
Clamp
Tool
WITH AIR
CONDITIONING
(A/C)

REMOVAL
If equipped with A/C, the generator and A/C com­
pressor along with their common mounting bracket (Fig. 17) must be partially removed. Removing the
generator or A/C compressor from their mounting
bracket is not necessary. Also, discharging the A/C system is not necessary. Do not remove any refrig­
erant lines from A/C compressor.

SUPPORT BRACKET (ROD)
GENERATOR/COMPRESSOR
MOUNTING
BRACKET

J9307-66

Fig.
17 Generator—A/C
Compressor
Mounting
Bracket—
Typical

WARNING;
THE A/C
SYSTEM
IS
UNDER
PRESSURE
EVEN
WITH
THE
ENGINE OFF. REFER
TO
REFRIG­

ERANT
WARNINGS
IN
GROUP
24,
HEATING
AND

AIR
CONDITIONING.

(1) Disconnect negative battery cable from battery. (2) Partially drain cooling system. Refer to Drain­
ing Cooling System in this group.
Do not waste reusable coolant. If the solution is
clean, drain the coolant into a clean container for re­
use.

(3) Remove upper radiator hose clamp at radiator.
Special Clamp Tool number 6094 (Fig. 16) may be
used to remove the constant tension clamps. Remove
hose at radiator.
(4) Disconnect throttle cable from clip at radiator
fan shroud. (5) Unplug wiring harness from A/C compressor.
(6) Remove the air cleaner assembly.
(7) Remove accessory drive belt. Refer to Belt Re­
moval/Installation in the Engine Accessory Drive
Belt section of this group.
(8) 3.9L/5.2L/5.9L LDC-Gas: The drive belt idler
pulley must be removed to gain access to one of the
A/C compressor/generator bracket mounting bolts. Remove the idler pulley bolt and remove idler pulley (Fig. 18).

GENERATOR/COMPRESSOR
AND
BRACKET

SUPPORT BRACKET

IGNITION

COIL
BRACKET
Fig.
18 Idler Pulley-3.9U5.2U5.9L
LDC-Gas
Engine
5.9L HDC-Gas: The automatic belt tensioner/pul-
ley assembly must be removed to gain access to one
of the A/C compressor/generator bracket mounting

bolts.
Remove the tensioner mounting bolt (Fig. 19) and remove tensioner.
(9) Remove the engine oil dipstick tube mounting
bolt at the side of the A/C-generator mounting
bracket.
(10) Disconnect throttle body control cables. Refer
to Accelerator Pedal and Throttle Cable in Group 14,
Fuel System.

7 - 22
COOLING
SYSTEM

•

Fig.
23 Bracket
Bolts—5.9L
HDC-Gas Engine
(2) Install bypass hose to engine.
(3) Secure both hose clamps.
(4) Install generator-A/C mounting bracket assem­
bly to engine. Tighten bolts (number 1 and 2 Fig. 17)
to 54 Nnn (40 ft. lbs.) torque. Tighten bracket mount­ ing bolts (Figs. 22 or 23) to 40 N-m (30 ft. lbs.)
torque.
(5) Install a new O-ring to the heater hose coolant
return tube (Figs. 20 or 21). Coat the new O-ring
with antifreeze before installation. (6) Install coolant return tube and its mounting
bolt to engine (Figs. 20 or 21). (7) Connect throttle body control cables.
(8) Install oil dipstick mounting bolt.
(9) 3.9L/5.2L/5.9L LDC-Gas: Install idler pulley.
Tighten bolt to 54 Nnn (40 ft. lbs.) torque. 5.9L HDC-Gas: Install automatic belt tensioner
assembly to mounting bracket. A dowel pin is located
on back of tensioner (Fig. 24). Align this to dowel
hole (Fig. 25) in tensioner mounting bracket. Tighten
bolt to 41 N-m (30 ft. lbs.). (10) Install drive belt. Refer to Belt Removal/In­
stallation in the Engine Accessory Drive Belt section
of this group.

CAUTION:
When installing
the
serpentine
accessory

drive belt,
the
belt must
be
routed correctly.
If not,

the engine
may
overheat
due to the
water pump
ro­

tating
in the
wrong direction. Refer
to
Belt Schemat­
ics
in the
Engine
Accessory
Drive Belt section
of

this
group
for
correct belt routing.
The
correct belt

with the
correct length must
be
used.

(11) Install air cleaner assembly.
BELT TENSIONER
DOWEL PIN
J9307-63

Fig.
24 Tensioner
Dowel
Pin—5.9L
HDC-Gas Engine Fig.
25 Tensioner
Mounting
Bracket
Dowel

Hote—5.9L
HDC-Gas Engine

(12) Install upper radiator hose to radiator.
(13) Connect throttle cable to clip at radiator fan
shroud.
(14) Connect wiring harness to A/C compressor. (15) Fill cooling system. Refer to Refilling Cooling
System in this group.
(16) Start and warm the engine. Check for leaks.

THERMOSTAT
GENERAL
INFORMATION
The thermostat on all gas powered engines is lo­
cated beneath the thermostat housing at the front of
the intake manifold (Fig. 26). The thermostat has an air bleed notch.
The thermostat of the 5.9L diesel engine is located
in the thermostat housing at front of cylinder head.
This is on exhaust manifold side of engine (Fig. 27). The thermostat is a wax pellet driven, reverse pop­
pet choke type. The wax pellet is located in a sealed container at the spring end of the thermostat. When
heated, the pellet expands, overcoming closing spring