belt DODGE RAM 2002 Service Owner's Guide

ENGINE COOLANT
THERMOSTAT - 5.9L
DESCRIPTION
CAUTION: Do not operate an engine without a ther-
mostat, except for servicing or testing.
The thermostat on the 5.9L gas powered engine 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, thepellet 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.
(4) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL) (Fig. 17).
(5) Remove two generator mounting bolts. Do not
remove any wiring at generator. If equipped with
4WD, unplug 4WD indicator lamp wiring harness
(located near rear of generator).
Fig. 15 Thermostat - 5.9L Gas Powered Engines
1 - THERMOSTAT HOUSING
2 - GASKET
3 - INTAKE MANIFOLD
4 - THERMOSTAT
5 - MACHINED GROOVE
7 - 48 ENGINEBR/BE

(6) Remove generator. Position generator to gain
access for thermostat gasket removal.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYSWEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps (Fig. 18). If
replacement is necessary, use only an original
equipment clamp with matching number or letter.
(7) Remove radiator upper hose clamp and upper
hose at thermostat housing.
(8) Position wiring harness (behind thermostat
housing) to gain access to thermostat housing.
(9) Remove thermostat housing mounting bolts,
thermostat housing, gasket and thermostat (Fig. 19).
Discard old gasket.
INSTALLATION
(1) Clean mating areas of intake manifold and
thermostat housing.
(2) Install thermostat (spring side down) into
recessed machined groove on intake manifold (Fig.
19).
(3) Install gasket on intake manifold and over
thermostat (Fig. 19).
(4) Position thermostat housing to intake manifold.
Note the word FRONT stamped on housing (Fig. 20).
For adequate clearance, thismustbe placed towards
front of vehicle. The housing is slightly angled for-
ward after installation to intake manifold.
(5) Install two housing-to-intake manifold bolts.
Tighten bolts to 23 N´m (200 in. lbs.) torque.
(6) Install radiator upper hose to thermostat hous-
ing.
Fig. 16 Generator Support BracketÐ5.9L Engine
1 - IDLER PULLEY BUSHING
2 - A/C AND/OR GENERATOR MOUNTING BRACKET
3 - IDLER PULLEY
4 - SCREW AND WASHER
Fig. 17 Automatic Belt TensionerÐ5.9L Engines
1 - IDLER PULLEY
2 - TENSIONER
3 - FAN BLADE
Fig. 18 SPRING CLAMP SIZE LOCATION
1 - SPRING CLAMP SIZE LOCATION
BR/BEENGINE 7 - 49
ENGINE COOLANT THERMOSTAT - 5.9L (Continued)

CAUTION: When installing the serpentine accessory
drive belt, the belt must be routed correctly. If not,
engine may overheat due to water pump rotating in
wrong direction. Refer to (Fig. 21) for correct 3.9L,
5.2L and 5.9L engine belt routing. The correct belt
with correct length must be used.
(7) Air Conditioned vehicles; Install generator.
Tighten bolts to 41 N´m (30 ft. lbs.).
(8) Install support bracket (generator mounting
bracket-to-intake manifold) (Fig. 16). Tighten bolts to
54 N´m (40 ft. lbs.) torque.
(9) Install accessory drive belt (Fig. 17)(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(10) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(11) Connect battery negative cable.
(12) Start and warm the engine. Check for leaks.
Fig. 19 ThermostatÐ5.9L Engines
1 - THERMOSTAT HOUSING
2 - GASKET
3 - INTAKE MANIFOLD
4 - THERMOSTAT
5 - MACHINED GROOVE
Fig. 20 Thermostat PositionÐ5.9L Engines
Fig. 21 Belt RoutingÐ5.9L Engines
1 - IDLER PULLEY
2 - GENERATOR PULLEY
3 - A/C COMPRESSOR PULLEY
4 - IF W/OUT A/C
5 - POWER STEERING PUMP PULLEY
6 - WATER PUMP PULLEY
7 - CRANKSHAFT PULLEY
8 - AUTOMATIC TENSIONER
7 - 50 ENGINEBR/BE
ENGINE COOLANT THERMOSTAT - 5.9L (Continued)

(1) Drill a 3.18-mm (1/8-in) diameter hole in the
top center of the fan shroud.
(2) Obtain a dial thermometer with an 8 inch stem
(or equivalent). It should have a range of -18É-to-
105ÉC (0É-to-220É F). Insert thermometer through the
hole in the shroud. Be sure that there is adequate
clearance from the fan blades.
(3) Connect a tachometer and an engine ignition
timing light. The timing light is to be used as a
strobe light. This step cannot be used on the diesel
engine.
(4) Block the air flow through the radiator. Secure
a sheet of plastic in front of the radiator (or air con-
ditioner condenser). Use tape at the top to secure the
plastic and be sure that the air flow is blocked.
(5) Be sure that the air conditioner (if equipped) is
turned off.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(6) Start the engine and operate at 2400 rpm.
Within ten minutes the air temperature (indicated on
the dial thermometer) should be up to 88É C (190É F).
Fan driveengagementshould start to occur at/be-
tween:
²5.9L gas engines Ð 79É C (175É F)
²8.0L engine Ð 88É to 96É C (190É to 205É F)
²5.9L diesel engine Ð 71É to 82É C (160É to 179É
F) Engagement is distinguishable by a definite
increasein fan flow noise (roaring). The timing light
also will indicate an increase in the speed of the fan
(non-diesel only).
(7) When viscous drive engagement is verified,
remove the plastic sheet. Fan drivedisengagement
should start to occur at between 57É to 79É C (135É to
175É F). A definitedecreaseof fan flow noise (roar-
ing) should be noticed. If not, replace the defective
viscous fan drive unit.
CAUTION: Some engines equipped with serpentine
drive belts have reverse rotating fans and viscous
fan drives. They are marked with the word
REVERSE to designate their usage. Installation of
the wrong fan or viscous fan drive can result in
engine overheating.
CAUTION: If the viscous fan drive is replaced
because of mechanical damage, the cooling fan
blades should also be inspected. Inspect for fatigue
cracks, loose blades, or loose rivets that could
have resulted from excessive vibration. Replace fan
blade assembly if any of these conditions arefound. Also inspect water pump bearing and shaft
assembly for any related damage due to a viscous
fan drive malfunction.
FAN DRIVE VISCOUS CLUTCH
- 5.9L DIESEL
DESCRIPTION
The thermal viscous fan drive (Fig. 30) is a sili-
cone-fluid- filled coupling used to connect the fan
blades to the water pump shaft. The coupling allows
the fan to be driven in a normal manner. This is
done at low engine speeds while limiting the top
speed of the fan to a predetermined maximum level
at higher engine speeds.
OPERATION
A thermostatic bimetallic spring coil is located on
the front face of the viscous fan drive unit (a typical
viscous unit is shown in (Fig. 31). This spring coil
reacts to the temperature of the radiator discharge
air. It engages the viscous fan drive for higher fan
speed if the air temperature from the radiator rises
above a certain point. Until additional engine cooling
is necessary, the fan will remain at a reduced rpm
regardless of engine speed.
Only when sufficient heat is present, will the vis-
cous fan drive engage. This is when the air flowing
through the radiator core causes a reaction to the
Fig. 30 Viscous Fan
1 - THREADED SHAFT
2 - BOLT (4)
3 - FAN BLADE
4 - THREADED NUT
5 - VISCOUS FAN DRIVE
7 - 56 ENGINEBR/BE
FAN DRIVE VISCOUS CLUTCH - 5.9L/8.0L (Continued)

bimetallic coil. It then increases fan speed to provide
the necessary additional engine cooling.
Once the engine has cooled, the radiator discharge
temperature will drop. The bimetallic coil again
reacts and the fan speed is reduced to the previous
disengaged speed.
DIAGNOSIS AND TESTING - VISCOUS FAN
DRIVE
NOISE
NOTE: It is normal for fan noise to be louder (roar-
ing) when:
²The underhood temperature is above the engage-
ment point for the viscous drive coupling. This may
occur when ambient (outside air temperature) is very
high.
²Engine loads and temperatures are high such as
when towing a trailer.
²Cool silicone fluid within the fan drive unit is
being redistributed back to its normal disengaged
(warm) position. This can occur during the first 15
seconds to one minute after engine start-up on a cold
engine.
LEAKS
Viscous fan drive operation is not affected by small
oil stains near the drive bearing. If leakage appears
excessive, replace the fan drive unit.
VISCOUS DRIVE
If the fan assembly free-wheels without drag (the
fan blades will revolve more than five turns whenspun by hand), replace the fan drive. This spin test
must be performed when the engine is cool.
For the following test, the cooling system must be
in good condition. It also will ensure against exces-
sively high coolant temperature.
WARNING: BE SURE THAT THERE IS ADEQUATE
FAN BLADE CLEARANCE BEFORE DRILLING.
(1) Drill a 3.18-mm (1/8-in) diameter hole in the
top center of the fan shroud.
(2) Obtain a dial thermometer with an 8 inch stem
(or equivalent). It should have a range of -18É-to-
105ÉC (0É-to-220É F). Insert thermometer through the
hole in the shroud. Be sure that there is adequate
clearance from the fan blades.
(3) Connect a tachometer and an engine ignition
timing light. The timing light is to be used as a
strobe light. This step cannot be used on the diesel
engine.
(4) Block the air flow through the radiator. Secure
a sheet of plastic in front of the radiator (or air con-
ditioner condenser). Use tape at the top to secure the
plastic and be sure that the air flow is blocked.
(5) Be sure that the air conditioner (if equipped) is
turned off.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(6) Start the engine and operate at 2400 rpm.
Within ten minutes the air temperature (indicated on
the dial thermometer) should be up to 88É C (190É F).
Fan driveengagementshould start to occur at/be-
tween:
²5.9L gas engines Ð 79É C (175É F)
²8.0L engine Ð 88É to 96É C (190É to 205É F)
²5.9L diesel engine Ð 71É to 82É C (160É to 179É
F) Engagement is distinguishable by a definite
increasein fan flow noise (roaring). The timing light
also will indicate an increase in the speed of the fan
(non-diesel only).
(7) When viscous drive engagement is verified,
remove the plastic sheet. Fan drivedisengagement
should start to occur at between 57É to 79É C (135É to
175É F). A definitedecreaseof fan flow noise (roar-
ing) should be noticed. If not, replace the defective
viscous fan drive unit.
Fig. 31 Viscous Fan DriveÐTypical
1 - VISCOUS FAN DRIVE
2 - THERMOSTATIC SPRING
3 - MOUNTING NUT TO WATER PUMP HUB
BR/BEENGINE 7 - 57
FAN DRIVE VISCOUS CLUTCH - 5.9L DIESEL (Continued)

CAUTION: Some engines equipped with serpentine
drive belts have reverse rotating fans and viscous
fan drives. They are marked with the word
REVERSE to designate their usage. Installation of
the wrong fan or viscous fan drive can result in
engine overheating.
CAUTION: If the viscous fan drive is replaced
because of mechanical damage, the cooling fan
blades should also be inspected. Inspect for fatigue
cracks, loose blades, or loose rivets that could
have resulted from excessive vibration. Replace fan
blade assembly if any of these conditions are
found. Also inspect water pump bearing and shaft
assembly for any related damage due to a viscous
fan drive malfunction.
RADIATOR - 5.9L
DESCRIPTION
The radiator is a aluminum cross-flow design with
horizontal tubes through the radiator core and verti-
cal plastic side tanks (Fig. 32).
This radiator contains an internal transmission oil
cooler only on the V-10 gas engine and the 5.9L die-
sel engine combinations.
OPERATION
The radiator supplies sufficient heat transfer using
the cooling fins interlaced between the horizontal
tubes in the radiator core to cool the engine.
DIAGNOSIS AND TESTINGÐRADIATOR
COOLANT FLOW
Use the following procedure to determine if coolant
is flowing through the cooling system.
(1) Idle engine until operating temperature is
reached. If the upper radiator hose is warm to the
touch, the thermostat is opening and coolant is flow-
ing to the radiator.
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING. USING A RAG TO
COVER THE RADIATOR PRESSURE CAP, OPEN
RADIATOR CAP SLOWLY TO THE FIRST STOP. THIS
WILL ALLOW ANY BUILT-UP PRESSURE TO VENT
TO THE RESERVE/OVERFLOW TANK. AFTER PRES-
SURE BUILD-UP HAS BEEN RELEASED, REMOVE
CAP FROM FILLER NECK.
(2) Drain a small amount of coolant from the radi-
ator until the ends of the radiator tubes are visible
through the filler neck. Idle the engine at normal
operating temperature. If coolant is flowing past the
exposed tubes, the coolant is circulating.
REMOVAL
(1) Disconnect battery negative cables.
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR
DRAINCOCK WITH THE SYSTEM HOT AND UNDER
PRESSURE. SERIOUS BURNS FROM COOLANT
CAN OCCUR.
(2) Drain the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
Fig. 32 Cross Flow RadiatorÐTypical
1 - COOLING TUBES
2 - TANKS
7 - 58 ENGINEBR/BE
FAN DRIVE VISCOUS CLUTCH - 5.9L DIESEL (Continued)

INSPECTION
Hold cap at eye level, right side up. The vent valve
(Fig. 45) at bottom of cap should open. If rubber gas-
ket has swollen and prevents vent valve from open-
ing, replace cap.
Hold cap at eye level, upside down. If any light can
be seen between vent valve and rubber gasket,
replace cap.Do not use a replacement cap that
has a spring to hold vent shut.A replacement cap
must be the type designed for a coolant reserve/over-
flow system with a completely sealed diaphragm
spring and a rubber gasket. This gasket is used to
seal to radiator filler neck top surface. Use of proper
cap will allow coolant return to radiator.
WATER PUMP - 5.9L
DESCRIPTION
The water pump is located on the engine front
cover, and has an integral pulley attached (Fig. 46).
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
antifreeze in the coolant mixture. Additional lubrica-
tion is not necessary.
OPERATION
A centrifugal water pump circulates coolant
through the water jackets, passages, intake manifold,
radiator core, cooling system hoses and heater core,this coolant absorbs the heat generated when the
engine is running. The pump is driven by the engine
crankshaft via a drive belt.
DIAGNOSIS AND TESTINGÐWATER PUMP
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.
REMOVAL
The water pump on all models can be removed
without discharging the air conditioning system (if
equipped).
The water pump on all gas powered engines is
bolted directly to the engine timing chain case/cover.
On the 5.9L gas powered engine, 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
fatigue 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 7 -
COOLING/ENGINE/FAN DRIVE VISCOUS
CLUTCH - DIAGNOSIS AND TESTING).
(1) Disconnect negative cable from battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
Fig. 45 Radiator Pressure Cap
1 - STAINLESS-STEEL SWIVEL TOP
2 - RUBBER SEALS
3 - VENT VALVE
4 - RADIATOR TANK
5 - FILLER NECK
6 - OVERFLOW NIPPLE
7 - MAIN SPRING
8 - GASKET RETAINER
Fig. 46 Water Pump LocationÐTypical
1 - WATER PUMP BYPASS HOSE
2 - FAN BLADE ASSEMBLY
3 - VISCOUS FAN DRIVE
4 - WATER PUMP AND PULLEY
7 - 66 ENGINEBR/BE
RADIATOR PRESSURE CAP (Continued)

(3) Remove windshield washer reservoir tank from
radiator fan shroud.
(4) Disconnect the coolant reserve/overflow tank-
to-radiator hose at the tank.
(5) Remove the four fan shroud mounting bolts at
the radiator (Fig. 47). Do not attempt to remove
shroud from vehicle at this time.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(6) Remove upper radiator hose at radiator.
(7) The thermal viscous fan drive is attached
(threaded) to the water pump hub shaft (Fig. 49).
Remove 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 with Special Tool
6958 Spanner Wrench and Adapter Pins 8346 (Fig.
48) to prevent the pulley from rotating.(8) If water pump is being replaced, do not unbolt
fan blade assembly (Fig. 49) from the thermal control
fan drive.
(9) Remove fan blade/fan drive and fan shroud as
an assembly from vehicle.
(10) After removing fan blade/fan drive assembly,
do notplace the thermal viscous fan drive in the
horizontal position. If stored horizontally, the silicone
fluid in the viscous drive could drain into its bearing
assembly and contaminate the bearing lubricant.
(11) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL) (Fig. 50).
(12) Remove the lower radiator hose and heater
hose from water pump.
(13) Loosen heater hose coolant return tube
mounting bolt (Fig. 51) and remove tube from water
pump. Discard the old tube O-ring.
(14) Remove the seven water pump mounting bolts
(Fig. 52).
(15) Loosen the clamp at the water pump end of
bypass hose (Fig. 49). Slip the bypass hose from the
water pump while removing pump from vehicle. Do
not remove the clamp from the bypass hose.
(16) Discard old gasket.
CAUTION: Do not pry the water pump at timing
chain case/cover. The machined surfaces may be
damaged resulting in leaks.
Fig. 47 Typical Fan Shroud Mounting
1 - RADIATOR SUPPORT
2 - RADIATOR
3 - BOLTS (4)
4 - FAN SHROUD
Fig. 48 Using Special Tool 6958 Spanner Wrench
and Adapter Pins 8346
1 - SPECIAL TOOL 6958 SPANNER WRENCH WITH ADAPTER
PINS 8346
2-FAN
BR/BEENGINE 7 - 67
WATER PUMP - 5.9L (Continued)

CLEANING
Clean gasket mating surfaces as necessary.
INSPECTION
Visually inspect the water pump and replace if it
has any of the following conditions:
²The body is cracked or damaged²Water leaks from the shaft seal. This is evident
by traces of coolant below the vent hole
²Loose or rough turning bearing. Also inspect
thermal fan drive
²Impeller rubbing the pump body
INSTALLATION
(1) Clean gasket mating surfaces.
Fig. 49 Fan Blade and Viscous Fan Drive - Typical
1 - WATER PUMP BYPASS HOSE
2 - FAN BLADE ASSEMBLY
3 - VISCOUS FAN DRIVE
4 - WATER PUMP AND PULLEY
Fig. 50 Belt Tensioner 5.9L V-8 Engine
1 - IDLER PULLEY
2 - TENSIONER
3 - FAN BLADE
Fig. 51 Coolant Return Tube 5.9L V-8 Engine
1 - COOLANT RETURN TUBE
2 - WATER PUMP
3 - TUBE MOUNTING BOLT
4 - O-RING
Fig. 52 Water Pump Bolts - 5.9L V-8 Gas Engine -
Typical
1 - WATER PUMP MOUNTING BOLTS
7 - 68 ENGINEBR/BE
WATER PUMP - 5.9L (Continued)

(2) Using a new gasket, install water pump to
engine as follows: Guide water pump nipple into
bypass hose as pump is being installed. Install water
pump bolts (Fig. 52). Tighten water pump mounting
bolts to 40 N´m (30 ft. lbs.) torque.
(3) Position bypass hose clamp to bypass hose.
(4) Spin water pump to be sure that pump impel-
ler does not rub against timing chain case/cover.
(5) Install a new o-ring to the heater hose coolant
return tube (Fig. 51). Coat the new o-ring with anti-
freeze before installation.
(6) Install coolant return tube and its mounting
bolt to engine (Fig. 51). Be sure the slot in tube
bracket is bottomed to mounting bolt. This will prop-
erly position return tube.
(7) Connect radiator lower hose to water pump.
(8) Connect heater hose and hose clamp to coolant
return tube.
(9) Install drive belt (Refer to 7 - COOLING/AC-
CESSORY DRIVE/DRIVE BELTS - INSTALLATION)
(Fig. 50).
(10) Position fan shroud and fan blade/viscous fan
drive assembly to vehicle as a complete unit.
(11) Install fan shroud.
(12) Install fan blade/viscous fan drive assembly to
water pump shaft.
(13) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(14) Connect negative battery cable.
(15) Start and warm the engine. Check for leaks.
WATER PUMP - 8.0L
DIAGNOSIS AND TESTINGÐWATER PUMP
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.
REMOVAL
NOTE:
The water pump on all models can be removed
without discharging the air conditioning system (if
equipped).
The water pump on all gas powered engines is
bolted directly to the engine timing chain case/
cover.
On the 8.0L V-10 engine, a rubber o-ring (instead of
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
fatigue cracks, loose blades or loose rivets that couldhave 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 7 -
COOLING/ENGINE/FAN DRIVE VISCOUS
CLUTCH - DIAGNOSIS AND TESTING).
(1) Disconnect negative battery cable from battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
Do not waste reusable coolant. If solution is clean,
drain coolant into a clean container for reuse.
(3) Remove windshield washer reservoir tank from
radiator fan shroud.
(4) Remove the four fan shroud mounting bolts at
the radiator (Fig. 53). Do not attempt to remove
shroud from vehicle at this time.
WARNING: CONSTANT TENSION HOSE CLAMPS
ARE USED ON MOST COOLING SYSTEM HOSES.
WHEN REMOVING OR INSTALLING, USE ONLY
TOOLS DESIGNED FOR SERVICING THIS TYPE OF
CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER
6094). SNAP-ON CLAMP TOOL (NUMBER HPC-20)
MAY BE USED FOR LARGER CLAMPS. ALWAYS
WEAR SAFETY GLASSES WHEN SERVICING CON-
STANT TENSION CLAMPS.
CAUTION: A number or letter is stamped into the
tongue of constant tension clamps. If replacement
is necessary, use only an original equipment clamp
with a matching number or letter.
(5) Remove radiator upper hose at radiator.
(6) The thermal viscous fan drive is attached
(threaded) to the water pump hub shaft (Fig. 55).
Fig. 53 Typical Fan Shroud Mounting
1 - RADIATOR SUPPORT
2 - RADIATOR
3 - BOLTS (4)
4 - FAN SHROUD
BR/BEENGINE 7 - 69
WATER PUMP - 5.9L (Continued)