clock DODGE RAM 2003 Service Repair Manual

To adjust the vehicle height turn the torsion bar
adjustment bolt CLOCKWISE to raise the vehicle
and COUNTER CLOCKWISE to lower the vehicle.
CAUTION: ALWAYS raise the vehicle to the correct
suspension height, NEVER lower the vehicle to
obtain the correct suspension height. If the vehicle
suspension height is too high, lower the vehicle
below the height specification. Then raise the vehi-
cle to the correct suspension height specification.
This will insure the vehicle maintains the proper
suspension height.
NOTE: If a height adjustment has been made, per-
form height measurement again on both sides of
the vehicle.
STANDARD PROCEDURE - CAMBER AND
CASTER ADJUSTMENT
NOTE: 4X4 (LD) SUSPENSION HEIGHT MEASURE-
MENT MUST BE PERFORMED BEFORE AN ALIGN-
MENT.
NOTE: When the upper control arm pivot bolts are
loosened the upper control arm will normally go
inwards toward the frame automatically with the
weight of the vehicle.
Camber and caster angle adjustments involve
changing the position of the upper control arm incon-
junction with the slotted holes in the frame brackets,
Install special tool 8876 between the top of the upper
control arm bracket and the upper control arm (on
1500 series 4X2 & 4X4). Install special tool 8876
between the bottom of the upper control arm bracket
pressing the tool against the frame and the upper
control arm (on 2500/3500 series 4X2) in order to
move the upper control arm outwards for proper
adjustment with the vehicle at normal ride height
(Fig. 3).
STANDARD PROCEDURE - TOE ADJUSTMENT
4X4 SUSPENSION HEIGHT MESUREMENT
MUST BE PERFORMED BEFORE AN ALIGN-
MENT.
The wheel toe position adjustment is the final
adjustment.
(1) Start the engine and turn wheels both ways
before straightening the wheels. Secure the steering
wheel with the front wheels in the straight-ahead
position.
(2) Loosen the tie rod jam nuts.NOTE: Each front wheel should be adjusted for
one-half of the total toe position specification. This
will ensure the steering wheel will be centered
when the wheels are positioned straight-ahead.
(3) Adjust the wheel toe position by turning the
inner tie rod as necessary (Fig. 4).
(4) Tighten the tie rod jam nut to 75 N´m (55 ft.
lbs.).
(5) Verify the specifications
(6) Turn off engine.
STANDARD PROCEDURE - CAMBER, CASTER
AND TOE ADJUSTMENT
NOTE: 4X4 (LD) SUSPENSION HEIGHT MEASURE-
MENT MUST BE PERFORMED BEFORE AN ALIGN-
MENT.
Camber and caster angle adjustments involve
changing the position of the upper control arm with
the slots in the frame brackets using special tool
8876 to move the upper control arm outwards for
proper adjustment. (Fig. 3)
NOTE: When the upper control arm pivot bolts are
loosened the upper control arm will normally go
inwards toward the frame automatically with the
weight of the vehicle.
CASTER
Moving the front or rear position of the upper con-
trol arm in or out, will change the caster angle and
camber angle significantly. To maintain the camber
Fig. 3 CASTER & CAMBER ADJUSTMENT
1 - FRONT PIVOT BOLT
2 - REAR PIVOT BOLT
3 - SLOTTED HOLES FOR ADJUSTMENT OF CASTER &
CAMBER
4 - UPPER CONTROL ARM
2 - 4 WHEEL ALIGNMENTDR
WHEEL ALIGNMENT (Continued)

INSTALLATION
INSTALLATION - 4X4
(1) Install the stabilizer link to the vehicle.
(2) Install the lower nut and Tighten to 102 N´m
(75 ft. lbs.).
(3) Install the retainers, grommets and upper nut
and Tighten to 38 N´m (27 ft. lbs.).
(4) Remove the support and lower the vehicle.
INSTALLATION - 4X2
(1) Install the stabilizer link to the vehicle (Fig.
29).
(2) Install the lower nut and Tighten to 102 N´m
(75 ft. lbs.).
(3) Install the retainers, grommets and upper nut
and Tighten to 38 N´m (27 ft. lbs.).
(4) Remove the support and lower the vehicle.
TORSION BAR
DESCRIPTION
The front of the bar connects to the back side of
the lower suspension arm. The rear end of the bar is
mounted in a anchor that rests in the frame cross-
member.
OPERATION
The torsion bars are used to control ride height
and ride quality. The vehicle height is adjusted
through an anchor adjustment bolt that increases or
decreases the wind up of the torsion bar. Increasing
or decreasing the bar angle changes the wind up of
the suspension arms.
REMOVAL
CAUTION: The left and right side torsion bars are
NOT interchangeable. The bars are identified and
stamped R or L, for right or left. The bars do not
have a front or rear end and can be installed with
either end facing forward.
(1) Raise and support the vehicle with the front
suspension hanging.
(2) Remove the transfer case skid plate (Refer to
13 - FRAME & BUMPERS/FRAME/TRANSFER
CASE SKID PLATE - REMOVAL).
NOTE: Count and record the number of turns for
installation reference.
(3) Mark the adjustment bolt setting.
(4) Install Special Tool - 8686 to the anchor arm
and the cross member (Fig. 30).(5) Increase the tension on the anchor arm tool
until the load is removed from the adjustment bolt
and the adjuster nut (Fig. 30).
(6) Turn the adjustment bolt counterclockwise to
remove the bolt and the adjuster nut..
(7) Remove the Special Tool - 8686, allowing the
torsion bar to unload (Fig. 30).
(8) Remove torsion bar and anchor. Remove anchor
from torsion bar (Fig. 31).
(9) Remove all foreign material from torsion bar
mounting in anchor and suspension arm.
(10) Inspect adjustment bolt, bearing and swivel
for damage.
Fig. 30 LOADING/UNLOADING TORSION BAR
1 - SPECIAL TOOL ± 8686
2 - CROSSMEMBER
Fig. 31 TORSION BAR
1 - ANCHOR
2 - SWIVEL
3 - TORSION BAR
4 - LOWER CONTROL ARM
DRFRONT - INDEPENDENT FRONT SUSPENSION 2 - 25
STABILIZER LINK (Continued)

INSTALLATION
CAUTION: The left and right side torsion bars are
NOT interchangeable. The bars are identified and
stamped R or L, for right or left. The bars do not
have a front or rear end and can be installed with
either end facing forward.
(1) Insert torsion bar ends into anchor and suspen-
sion arm.
(2) Position the anchor in the frame crossmember.
(3) Install Special Tool - 8686 to the anchor and
the crossmember (Fig. 30).
(4) Increase the tension on the anchor in order to
load the torsion bar.
(5) Install the adjustment bolt and the adjuster
nut.
(6) Turn adjustment bolt clockwise the recorded
amount of turns.
(7) Remove tool - 8686 from the torsion bar cross-
member (Fig. 30).
(8) Install the transfer case skid plate (Refer to 13
- FRAME & BUMPERS/FRAME/TRANSFER CASE
SKID PLATE - INSTALLATION).
(9) Lower vehicle and adjust the front suspension
height (Refer to 2 - SUSPENSION/WHEEL ALIGN-
MENT - STANDARD PROCEDURE).
(10) Perform a wheel alignment (Refer to 2 - SUS-
PENSION/WHEEL ALIGNMENT - STANDARD
PROCEDURE).
UPPER BALL JOINT
DIAGNOSIS AND TESTING - UPPER BALL
JOINT
NOTE: If the ball joint is equipped with a lubrication
fitting, grease the joint then road test the vehicle
before performing test.
(1) Raise the front of the vehicle. Place safety floor
stands under both lower control arms as far outboard
as possible. Lower the vehicle to allow the stands to
support some or all of the vehicle weight.
(2) Remove the front tires.(3) Mount a dial indicator solidly to the frame and
then zero the dial indicator.
(4) Position dial indicator plunger on the topside of
the upper ball joint (Fig. 32).
NOTE: The dial indicator plunger must be perpen-
dicular to the machined surface of the ball joint
(Fig. 32).
NOTE: Use care not to pry or tear the ball joint
boot, when checking the free play.
(5) Position a pry bar between the steering
knuckle and the upper control arm. Pry upwards on
the upper control arm (Fig. 32).
(6) If the travel exceeds 0.5 mm (0.020 in.), replace
the upper control arm since the upper ball joint is
integral to the arm (Refer to 2 - SUSPENSION/
FRONT/UPPER CONTROL ARM - REMOVAL).
(7) If the upper ball joint is within specs reinstall
the front tires (Refer to 22 - TIRES/WHEELS/
WHEELS - STANDARD PROCEDURE).
Fig. 32 UPPER BALL JOINT PLAY
1 - DIAL INDICATOR
2 - UPPER CONTROL ARM
3-PRYBAR
4 - KNUCKLE
5 - BALL JOINT BOOT
2 - 26 FRONT - INDEPENDENT FRONT SUSPENSIONDR
TORSION BAR (Continued)

(9) Subtract each reading from the one 180É oppo-
site to determine runout and direction. Bore runout
example (Fig. 10):
²0.000 ± (±0.007) = 0.007 in.
²+0.002 ± (±0.010) = 0.012 in.
²+0.004 ± (±0.005) = 0.009 in.
²±0.001 ± (+0.001) = ±0.002 in.
In this example the largest or total indicator read-
ing (TIR) difference is 0.012 inch. This means the
housing bore is offset from the crankshaft centerline
by 0.006 in. which is 1/2 of 0.012 inch. The dowels
needed to correct this have an offset of 0.007 in. (Fig.
11).
Remove housing and install dowels with the slotted
side facing out so they can be turned with a screw-driver. Then install the housing and mount the dial
indicator and check bore runout again. Rotate the
dowels until the TIR is less than 0.010 inch.
Clutch Housing Face Runout
(1) Position dial indicator towards the housing face
(Fig. 12) with indicator plunger on the rim of the
housing bore.
(2) Rotate crankshaft until indicator plunger is at
the 10 O'clock position and zero the dial indicator.
(3) Measure and record face runout readings at
four points 90É apart (Fig. 13). Take measurement at
least twice for accuracy.
(4) Subtract lowest reading from highest to deter-
mine total runout. If low reading wasminus0.004
in. and highest reading wasplus0.009 in. the total
runout is 0.013 inch.
Fig. 10 MEASUREMENT POINTS AND READINGS
1 - CLUTCH HOUSING BORE CIRCLE
Fig. 11 ALIGNMENT DOWEL SELECTION
1 - SLOT DIRECTION OF OFFSET
2 - OFFSET DOWEL
TIR VALUE OFFSET DOWEL REQUIRED
0.011 - 0.021 inch 0.007 inch
0.022 - 0.035 inch 0.014 inch
0.036 - 0.052 inch 0.021 inch
Fig. 12 DIAL INDICATOR LOCATION
1 - INDICATOR PLUNGER
2 - DIAL INDICATOR
3 - CLUTCH HOUSING FACE
4 - INDICATOR MOUNTING STUD OR ROD
Fig. 13 MEASUREMENT POINTS AND READINGS
1 - CLUTCH HOUSING FACE CIRCLE (AT RIM OF BORE)
DRCLUTCH 6 - 9
CLUTCH HOUSING (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
NOISE
(Objectionable squeal, squeak, or
rumble is heard or felt while drive
belt is in operation)1. Incorrect belt tension 1. Inspect/Replace tensioner if
necessary
2. Bearing noise 2. Locate and repair
3. Belt misalignment 3. Align belt/pulley(s)
4. Belt to pulley mismatch 4. Install correct belt
5. Driven component induced
vibration5. Locate defective driven
component and repair
TENSION SHEETING FABRIC
FAILURE
(Woven fabric on outside,
circumference of belt has cracked or
separated from body of belt)1. Tension sheeting contacting
stationary object1. Correct rubbing condition
2. Excessive heat causing woven
fabric to age2. Replace belt
3. Tension sheeting splice has
fractured3. Replace belt
CORD EDGE FAILURE
(Tensile member exposed at edges
of belt or separated from belt body)1. Incorrect belt tension 1. Inspect/Replace tensioner if
necessary
2. Belt contacting stationary object 2. Replace belt
3. Pulley(s) out of tolerance 3. Replace pulley
4. Insufficient adhesion between
tensile member and rubber matrix4. Replace belt
REMOVAL
NOTE: The belt routing schematics are published
from the latest information available at the time of
publication. If anything differs between these sche-
matics and the Belt Routing Label, use the sche-
matics on Belt Routing Label.This label is located in
the engine compartment.
CAUTION: Do not attempt to check belt tension with
a belt tension gauge on vehicles equipped with an
automatic belt tensioner. Refer to Automatic Belt
Tensioner in this group.
Drive belts on these engines are equipped with a
spring loaded automatic belt tensioner (Fig. 11). This
belt tensioner will be used on all belt configurations,
such as with or without power steering or air condi-
tioning. For more information, (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/BELT TENSIONERS -
DESCRIPTION).
(1) Attach a socket/wrench to pulley mounting bolt
of automatic tensioner (Fig. 11).
(2) Rotate tensioner assembly clockwise (as viewed
from front) until tension has been relieved from belt.
(3) Remove belt from idler pulley first.
(4) Remove belt from vehicle.
Fig. 11 Belt Tensioner - 5.9L Gas Engines
1 - IDLER PULLEY
2 - TENSIONER
3 - FAN BLADE
7 - 30 ACCESSORY DRIVEDR
DRIVE BELTS - 5.9L (Continued)

INSTALLATION
CAUTION: When installing the 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. 12) (Fig. 13) for correct
engine belt routing. The correct belt with correct
length must be used.
(1) Position drive belt over all pulleysexceptidler
pulley. This pulley is located between generator and
A/C compressor.
(2) Attach a socket/wrench to pulley mounting bolt
of automatic tensioner (Fig. 11).
(3) Rotate socket/wrench clockwise. Place belt over
idler pulley. Let tensioner rotate back into place.
Remove wrench. Be sure belt is properly seated on
all pulleys.
(4) Check belt indexing marks (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/BELT TENSIONERS -
DESCRIPTION).
DRIVE BELTS - 5.9L DIESEL
DIAGNOSIS AND TESTINGÐACCESSORY
DRIVE BELT
VISUAL DIAGNOSIS
When diagnosing serpentine accessory drive belts,
small cracks that run across the ribbed surface of the
belt from rib to rib (Fig. 14), are considered normal.
These are not a reason to replace the belt. However,
cracks running along a rib (not across) arenotnor-
mal. Any belt with cracks running along a rib must
be replaced (Fig. 14). Also replace the belt if it has
excessive wear, frayed cords or severe glazing.
Fig. 12 Belt Routing - 5.9L Engines with A/C
1 - GENERATOR PULLEY
2 - A/C PULLEY
3 - POWER STEERING PULLEY
4 - CRANKSHAFT PULLEY
5 - WATER PUMP PULLEY
6 - TENSIONER PULLEY
7 - IDLER PULLEY
Fig. 13 Belt Routing - 5.9L Engines Without A/C
1 - GENERATOR PULLEY
2 - IDLER PULLEY
3 - POWER STEERING PULLEY
4 - CRANKSHAFT PULLEY
5 - WATER PUMP PULLEY
6 - TENSIONER PULLEY
DRACCESSORY DRIVE 7 - 31
DRIVE BELTS - 5.9L (Continued)

NOTE: The engine speed sensor face is very close
to the accessory drive belt. Inspect engine speed
sensor and wire harness for damage when acces-
sory drive belt has been replaced due to failure or
abnormal conditions.
REMOVAL
CAUTION: Do not attempt to check belt tension with
a belt tension gauge on vehicles equipped with an
automatic belt tensioner. Refer to Automatic Belt
Tensioner in this group.
NOTE: The belt routing schematics are published
from the latest information available at the time of
publication. If anything differs between these sche-
matics and the Belt Routing Label, use the sche-
matics on Belt Routing Label.This label is located in
the engine compartment.
Drive belts on diesel engines are equipped with a
spring loaded automatic belt tensioner.displays the
tensioner for vehicles without air conditioning.
This belt tensioner will be used on all belt config-
urations, such as with or without air conditioning.
For more information, (Refer to 7 - COOLING/AC-
CESSORY DRIVE/BELT TENSIONERS - DESCRIP-
TION).
(1) A 1/2 inch square hole is provided in the auto-
matic belt tensioner. Attach a 1/2 inch drive-long
handle ratchet to this hole.
(2) Rotate ratchet and tensioner assembly clock-
wise (as viewed from front) until tension has been
relieved from belt.
(3) Remove belt from water pump pulley first.
(4) Remove belt from vehicle.
INSTALLATION
CAUTION: When installing the accessory drive belt,
the belt must be routed correctly. If not, engine mayoverheat due to water pump rotating in wrong
direction. Refer to (Fig. 15) for correct engine belt
routing. The correct belt with correct length must
be used.
(1) Position drive belt over all pulleysexcept
water pump pulley.
(2) Attach a 1/2 inch ratchet to tensioner.
(3) Rotate ratchet and belt tensioner clockwise.
Place belt over water pump pulley. Let tensioner
rotate back into place. Remove ratchet. Be sure belt
is properly seated on all pulleys.
Fig. 15 Belt Routing±5.9L Diesel Engine
1 - GENERATOR PULLEY
2 - WATER PUMP PULLEY
3 - IDLER PULLEY
4 - POWER STEERING PUMP PULLEY
5 - RADIATOR FAN PULLEY
6 - CRANKSHAFT PULLEY
7 - AUTOMATIC TENSIONER
8 - A/C COMPRESSOR PUMP PULLEY
7 - 34 ACCESSORY DRIVEDR
DRIVE BELTS - 5.9L DIESEL (Continued)

The air space also acts as sort of a spring that pro-
vides constant system pressurization in conjunction
with the radiator cap on top of the container. By
returning coolant to the pump side of the inlet ther-
mostat, the degas container also supplies greater
pressure to the coolant pump, providing for enhanced
coolant flow at high engine speeds.
The degas container also provides a convenient and
safe method for checking the coolant level with out
removing the radiator pressure cap. The degas con-
tainer does not require a separate overflow container
since it was designed with enough volume to provide
a coolant reserve and also protect for any after-boil
conditions.
REMOVAL
(1) Drain enough coolant from the system so that
the degas container is empty. Refer to Draining Cool-
ing System 3.7L/4.7L Engines in this group
(2) Loosen the clamps securing the supply and
return hoses to the container and remove the hoses.
(3) Remove the coolant container to fan shroud
mounting bolts.
(4) Tilt the container back towards the engine to
disengage the mounting pin locking features and lift
the container away from the fan shroud.
INSTALLATION
(1) Align the mounting pins into the slots on the
fan shroud and push the container into the fan
shroud.
(2) Secure the coolant container to the fan shroud
with bolts. Tighten to 8.5 N-m (75 in. lbs).
NOTE: Ensure the locking feature on the mounting
pins has engaged.
(3) Connect the supply and return hoses to the
container and ensure that the hose clamps are posi-
tioned properly.
(4) Refill the cooling system(Refer to 7 - COOLING
- STANDARD PROCEDURE).
RADIATOR FAN
REMOVAL
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.
(1) Disconnect negative battery cable from battery.
(2) Remove coolant reserve/overflow container from
fan shroud and lay aside.Do Notdisconnect the
hoses or drain coolant from the container.
(3) The thermal viscous fan drive/fan blade assem-
bly is attached (threaded) to the water pump hub
shaft (Fig. 4). Remove the fan blade/viscous fan drive
assembly from the water pump by turning the
mounting nut counterclockwise as viewed from the
front. Threads on the viscous fan drive areRIGHT-
HAND.A 36 MM Fan Wrench should be used to pre-
vent pulley from rotating (Fig. 3).
(4)Do Notattempt to remove the fan/viscous fan
drive assembly from the vehicle at this time.
(5)Do Notunbolt the fan blade assembly (Fig. 4)
from viscous fan drive at this time.
(6) Remove the fan shroud-to-radiator mounting
bolts.
(7) Pull the lower shroud mounts out of the radia-
tor tank clips.
(8) Remove the fan shroud and fan blade/viscous
fan drive assembly as a complete unit from vehicle.
(9) After removing the fan blade/viscous fan drive
assembly,do notplace the viscous fan drive in a
horizontal position. If stored horizontally, silicone
Fig. 2 Coolant Degas Container
1 - SCREWS
2 - COOLANT DEGAS CONTAINER
3 - FAN SHROUD
4 - RADIATOR
DRENGINE 7 - 39
COOLANT DEGAS CONTAINER-3.7L/4.7L (Continued)

RADIATOR FAN - 5.9L DIESEL
REMOVAL
CAUTION: If the electronically controlled viscous
fan drive is replaced because of mechanical dam-
age, the cooling fan blades should also be
inspected. Inspect for fatigue cracks, or loose rivets
that could have resulted from excessive vibration.
Replace fan blade assembly if any of these condi-
tions are found. Also inspect wiring harness and
connectors for damage.
(1) Disconnect the battery negative cables.
(2) Remove the fan shroud lower half. by unsnap-
ping the fastening tabs.
CAUTION: Do not remove the fan pulley bolts. This
pulley is under spring tension.
(3) Disconnect electrical connector.
(4) The electronically controlled viscous fan drive/
fan blade assembly is attached (threaded) to the fan
hub shaft (Fig. 5). Remove the fan blade/fan drive
assembly from fan pulley by turning the mounting
nut counterclockwise (as viewed from front). Threads
on the viscous fan drive areRIGHT-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
fan pulley bolts to prevent pulley from rotating.
(5) Remove the fan shroud and the fan blade/vis-
cous drive as an assembly from vehicle from under
the vehicle.
(6) Remove fan blade-to-viscous fan drive mount-
ing bolts.
(7) Inspect the fan for cracks, loose or bent fan
blades.
CAUTION: Some engines equipped with serpentine
drive belts have reverse rotating fans and viscous
fan drives. Installation of the wrong fan or viscous
fan drive can result in engine overheating.
CLEANING
Clean the fan blades using a mild soap and water.
Do not use an abrasive to clean the blades.
INSPECTION
WARNING: DO NOT ATTEMPT TO BEND OR
STRAIGHTEN FAN BLADES IF FAN IS NOT WITHIN
SPECIFICATIONS.CAUTION: If fan blade assembly is replaced
because of mechanical damage, water pump and
viscous fan drive should also be inspected. These
components could have been damaged due to
excessive vibration.
(1) Remove fan blade assembly from viscous fan
drive unit (six bolts).
(2) Lay fan on a flat surface with leading edge fac-
ing down. With tip of blade touching flat surface,
replace fan if clearance between opposite blade and
surface is greater than 2.0 mm (.090 inch). Rocking
motion of opposite blades should not exceed 2.0 mm
(.090 inch). Test all blades in this manner.
(3) Inspect fan assembly for cracks, bends, or bro-
ken welds. Replace fan if any damage is found.
INSTALLATION
(1) Install fan blade assembly to electrically con-
trolled viscous fan drive. Tighten mounting bolts to
23 N´m (17 ft. lbs.) torque.
(2) Position the fan blade/viscous fan drive to the
vehicle as an assembly.
(3) Install viscous fan drive assembly on fan hub
shaft (Fig. 5). Tighten mounting nut to 33 N´m (24 ft.
lbs.) torque.
(4) Connect electrical connector.
Fig. 5 Fan Blade/Viscous Fan Drive
1 - ELECTRICAL CONNECTOR
2 - VISCOUS FAN DRIVE
3 - FAN BLADE
4 - BOLT
5 - FAN DRIVE
DRENGINE 7 - 41

loaded pressure relief valve. This valve opens when
system pressure reaches the release range of 97-to-
124 kPa (14-to-18 psi).
A rubber gasket seals the radiator filler neck. This
is done to maintain vacuum during coolant cool-down
and to prevent leakage when system is under pres-
sure.
OPERATION
A vent valve in the center of the cap will remain
shut as long as the cooling system is pressurized. As
the coolant cools, it contracts and creates a vacuum
in the cooling system. This causes the vacuum valve
to open and coolant in the reserve/overflow container
to be drawn through the recovery hose connecting
the filler neck and reserve/overflow container. If the
vacuum valve is stuck shut, or the recovery hose is
kinked, radiator hoses will collapse on cool down.
For the 3.7L/4.7L engine, the vacuum valve will
open and relieve the vacuum pressure in the cooling
system.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐRADIATOR
CAP-TO-FILLER NECK SEAL
The pressure cap upper gasket (seal) pressure
relief can be tested by removing overflow hose from
the radiator filler neck tube. Attach the hose of the
pressure tester tool 7700 (or equivalent) to the tube.
It will be necessary to disconnect hose from its
adapter for the filler neck. Pump air into radiator.
The pressure cap upper gasket should relieve at 69
to 124kPa (10 to 18 psi) and hold pressure at a min-
imum of 55 kPa (8 psi).
WARNING: THE WARNING WORDS ÐDO NOT
OPEN HOTÐ ON RADIATOR PRESSURE CAP, ARE
A SAFETY PRECAUTION. WHEN HOT, PRESSURE
BUILDS UP IN COOLING SYSTEM. TO PREVENT
SCALDING OR INJURY, RADIATOR CAP SHOULD
NOT BE REMOVED WHILE SYSTEM IS HOT AND/OR
UNDER PRESSURE.
Do not remove the radiator cap at any timeexcept
for the following purposes:
(1) Check and adjust antifreeze freeze point.
(2) Refill the system with new antifreeze.
(3) Conducting service procedures.
(4) Checking for vacuum leaks.
WARNING: IF VEHICLE HAS BEEN RUN RECENTLY,
WAIT AT LEAST 15 MINUTES BEFORE REMOVING
RADIATOR CAP. WITH A RAG, SQUEEZE RADIATOR
UPPER HOSE TO CHECK IF SYSTEM IS UNDER
PRESSURE. PLACE A RAG OVER CAP AND WITH-
OUT PUSHING CAP DOWN, ROTATE IT COUNTER-
CLOCKWISE TO FIRST STOP. ALLOW FLUID TO
ESCAPE THROUGH THE COOLANT RESERVE/
OVERFLOW HOSE INTO RESERVE/OVERFLOW
TANK. SQUEEZE RADIATOR UPPER HOSE TO
DETERMINE WHEN PRESSURE HAS BEEN
RELEASED. WHEN COOLANT AND STEAM STOP
BEING PUSHED INTO TANK AND SYSTEM PRES-
SURE DROPS, REMOVE RADIATOR CAP COM-
PLETELY.
DIAGNOSIS AND TESTING - RADIATOR CAP
Remove the cap from the radiator. Be sure that the
sealing surfaces are clean. Moisten the rubber gasket
with water and install the cap on the pressure tester
7700 or an equivalent (Fig. 38).
Operate the tester pump to bring the pressure to
104 kPa (15 psi) on the gauge. If the pressure cap
fails to hold pressure of at least 97 kPa (14 psi)
replace the cap. Refer to the followingCAUTION.
Fig. 37 Radiator Pressure Cap - Typical
1 - FILLER NECK SEAL
2 - VACUUM VENT VALVE
3 - PRESSURE RATING
4 - PRESSURE VALVE
DRENGINE 7 - 61
RADIATOR PRESSURE CAP (Continued)