gasket CHRYSLER TOWN AND COUNTRY 2002 Service Manual

Replacebothdisc brake shoes (inboard and out-
board) on each caliper. It is necessary to replace the
shoes on the opposite side of the vehicle as well as
the shoes failing inspection.
If the brake shoe assemblies do not require
replacement, be sure to reinstall the brake shoes in
the original position they were removed from.
INSTALLATION
INSTALLATION - FRONT DISC BRAKE SHOES
NOTE: There may be more than 1 lining material
released. Make sure proper linings are being
installed.
(1) Begin on one side of the vehicle or the other.
(2) Completely retract the caliper piston back into
its bore in the brake caliper (This is required for cal-
iper installation on the brake rotor with new brake
shoes installed).
(3) If applied, remove the protective paper from
the noise suppression gasket on the rear of both the
inner and outer brake shoe assemblies.
(4) Install the new inboard brake shoe into the cal-
iper piston by firmly pressing its retaining clip into
the piston bore. Be sure the inboard brake shoe is
positioned squarely against the face of the caliper
piston.
(5) Lubricate both adapter abutments where the
shoes slide with a small amount of MopartDielectric
grease, or equivalent.
(6) Slide the new outboard brake shoe into the cal-
iper adapter with the lining up against the outside of
the brake rotor.
CAUTION: Use care when installing the caliper
assembly onto the caliper adapter, so the caliper
guide pin bushings do not get damaged by the
adapter bosses.
(7) Carefully position the brake caliper over the
brake rotor and adapter.
(8) Install the caliper guide pin bolts and tighten
to a torque of 35 N´m (26 ft. lbs.).Extreme caution
should be taken not to cross thread the caliper
guide pin bolts.
(9) Install the caps over the caliper guide pin bolts.
(10) Install the new caliper hold down spring (anti-
rattle clip) on the outboard side of the caliper. Start
the spring into the holes on the caliper, then stretch
the clip legs past the abutments on the caliper
adapter.
(11) Repeat the above procedure on other side of
the vehicle.(12) Install the wheel and tire assemblies. Tighten
the wheel mounting nuts in proper sequence until all
nuts are torqued to half specification, then repeat the
tightening sequence to the full specified torque of 135
N´m (100 ft. lbs.).
(13) Lower vehicle.
(14) Pump the brake pedal several times. This will
set the shoes to the brake rotor.
(15) Check and adjust brake fluid level as neces-
sary.
(16) Road test the vehicle and make several stops
to wear off any foreign material on the brakes and to
seat the brake shoes.
INSTALLATION - FRONT DISC BRAKE SHOES
(DISC/DRUM BRAKES)
NOTE: Perform steps Step 1 through Step 5on each
side of the vehicle.
(1) Place the brake shoes in the adapter anti-rattle
clips.
(2) Completely retract the caliper piston back into
the bore of the caliper.
CAUTION: Use care when installing the caliper onto
the disc brake adapter to avoid damaging the boots
on the caliper guide pins.
(3) Install the disc brake caliper over the brake
shoes on the brake caliper adapter.
(4) Align the caliper guide pin bolt holes with the
guide pins. Install the caliper guide pin bolts and
tighten them to a torque of 35 N´m (26 ft. lbs.) (Fig.
22).
(5) Install the tire and wheel assembly. Tighten
the wheel mounting nuts to a torque of 135 N´m (100
ft. lbs.).
(6) Lower the vehicle.
(7) Pump the brake pedal several times. This will
set the shoes to the brake rotor.
(8) Check and adjust the brake fluid level as nec-
essary.
(9) Road test the vehicle and make several stops to
wear off any foreign material on the brakes and to
seat the brake shoes.
BRAKE PADS/SHOES - REAR
DISC
REMOVAL - REAR DISC BRAKE SHOES
(1) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
RSBRAKES - BASE5-19
BRAKE PADS/SHOES - FRONT (Continued)
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SUPPORT PLATE - DRUM
BRAKE
REMOVAL
(1) Using a brake pedal depressor, move and
secure brake pedal to a position past its first 1 inch
of travel. This will prevent brake fluid from draining
out of master cylinder when brake tube is remove
from wheel cylinder.
(2) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
(3) Remove wheel and tire assembly.
(4) Disconnect brake tube from rear of wheel cylin-
der. Cap open ends
(5) Remove brake drum.
(6) Remove brake shoes from brake support plate.
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL/
BRAKE PADS/SHOES - REMOVAL).
(7) Remove the 2 bolts attaching the wheel cylin-
der to the brake support plate.
(8) Remove the wheel cylinder from the brake sup-
port plate.
(9) Disconnect the park brake cable from the park
brake actuation lever.
(10) Using a suitable tool such as a 14 mm box
wrench (Fig. 103) or an aircraft type hose clamp,
compress the flared legs on park brake cable
retainer. Then pull the park brake cable out of brake
support plate.(11) Remove the rear hub and bearing. (Refer to 2
- SUSPENSION/REAR/HUB / BEARING -
REMOVAL)
(12) Remove the rear brake support plate from the
rear axle.
INSTALLATION
(1) Install the 4 hub and bearing to axle mounting
bolts into the mounting holes in the flange of the
rear axle.
(2) Install the rear brake support plate on the 4
mounting bolts installed in the flange of the rear axle
(Fig. 104).
(3) Install the rear hub and bearing (and connect
wheel speed sensor where applicable) stopping short
of installing the brake drum. (Refer to 2 - SUSPEN-
SION/REAR/HUB / BEARING - INSTALLATION)
(4) Install the rear park brake cable into its
mounting hole in the rear brake support plate.
(5) Install the park brake cable on the park brake
actuation lever.
(6) Apply sealant such as Mopar Gasket-In-A-Tube
or equivalent around the wheel cylinder opening in
the brake support plate.
(7) Install wheel cylinder onto brake support.
Install and tighten the wheel cylinder to brake sup-
port plate attaching bolts to 8 N´m (75 in. lbs.)
torque.
(8) Install brake tube into wheel cylinder. Tighten
tube nut to a torque of 17 N´m (145 in. lbs.) torque.
(9) Install the rear brake shoes on the brake sup-
port plate. (Refer to 5 - BRAKES/HYDRAULIC/ME-
CHANICAL/BRAKE PADS/SHOES -
INSTALLATION).
(10) Install brake drum.
Fig. 103 Removing Park Brake Cable From Brake
Support Plate
1 - PARK BRAKE CABLE
2 - CABLE RETAINER
3 - 14 mm BOX WRENCH
4 - BRAKE SUPPORT PLATE
Fig. 104 Brake Support Plate Mounted On Bearing
Attaching Bolts
1 - REAR BRAKE SUPPORT PLATE
2 - HUB/BEARING MOUNTING BOLTS
5 - 64 BRAKES - BASERS
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(11) Install wheel and tire.
(12) Tighten wheel stud nuts to 135 N´m (100 ft.
lbs.).
(13) Adjust drum brake shoes. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/BRAKE
PADS/SHOES - ADJUSTMENTS)
(14) Remove brake pedal depressor tool.
(15) Bleed the brake system as necessary. (Refer to
5 - BRAKES - BASE - STANDARD PROCEDURE).
(16) Lower the vehicle.
WHEEL CYLINDERS
REMOVAL
(1) Using a brake pedal depressor, move and
secure brake pedal to a position past its first 1 inch
of travel. This will prevent brake fluid from draining
out of master cylinder when brake tube is remove
from wheel cylinder.
(2) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
(3) Remove wheel and tire assembly.
(4) Disconnect brake tube from rear of wheel cylin-
der. Cap open ends
(5) Remove brake drum.
(6) Remove brake shoes from brake support plate
(Discard if contaminated).(Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/BRAKE PADS/SHOES -
REMOVAL)
(7) Remove the 2 bolts attaching the wheel cylin-
der to the brake support plate.
(8) Remove the wheel cylinder from the brake sup-
port plate.
INSPECTION
With brake drums removed, inspect the wheel cyl-
inder boots for evidence of a brake fluid leak. Visu-
ally check the boots for cuts, tears, or heat cracks. If
any of these conditions exist, the wheel cylinders
should be completely cleaned, inspected and new
parts installed.
If a wheel cylinder is leaking and the brake lining
material is saturated with brake fluid, the brake
shoes must be replaced.
INSTALLATION
(1) Apply sealant such as Mopar Gasket-In-A-Tube
or equivalent around the wheel cylinder opening in
the brake support plate.
(2) Install wheel cylinder onto brake support.
Install and tighten the wheel cylinder to brake sup-
port plate attaching bolts to 8 N´m (75 in. lbs.)
torque.(3) Install brake tube into wheel cylinder. Tighten
tube nut to a torque of 17 N´m (145 in. lbs.) torque.
(4) Install the rear brake shoes on the brake sup-
port plate. (Refer to 5 - BRAKES/HYDRAULIC/ME-
CHANICAL/BRAKE PADS/SHOES -
INSTALLATION).
(5) Install brake drum.
(6) Install wheel and tire. Install and tighten
wheel lug nuts to 135 N´m (100 ft. lbs.).
(7) Adjust drum brake shoes. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/BRAKE
PADS/SHOES - ADJUSTMENTS)
(8) Remove brake pedal depressor tool.
(9) Bleed the brake system as necessary. (Refer to
5 - BRAKES - BASE - STANDARD PROCEDURE).
(10) Lower vehicle.
PARKING BRAKE
DESCRIPTION
DESCRIPTION
The parking brake system is operated by a foot
operated parking brake lever. The parking brake
lever is mounted on the body of the vehicle to the left
of the brake pedal (Fig. 105). It is a automatic-ad-
justing type lever.
Fig. 105 Parking Brake Lever (Pedal)
1 - PARK BRAKE PEDAL ASSEMBLY
2 - PARK BRAKE PEDAL
3 - CARPET
4 - FRONT PARK BRAKE CABLE
5 - SEAL
6 - FLOOR PAN
RSBRAKES - BASE5-65
SUPPORT PLATE - DRUM BRAKE (Continued)
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With engine not running, remove radiator pressure
cap and wipe the radiator filler neck sealing seat
clean. The radiator should be full.
Attach the Cooling System Tester 7700 or equiva-
lent to the radiator, as shown in (Fig. 4) and apply
104 kPa (15 psi) pressure. If the pressure drops more
than 13.8 kPa (2 psi) in 2 minutes, inspect all points
for external leaks.
All radiator and heater hoses should be shaken
while at 104 kPa (15 psi), since some leaks occur only
while driving due to engine movement.If there are no external leaks, after the gauge dial
shows a drop in pressure, detach the tester. Start
engine and run until the thermostat opens, allowing
the coolant to expand. Reattach the cooling system
tester. If the needle on the dial fluctuates it indicates
a combustion leak, usually a head gasket leak.
WARNING: WITH TOOL IN PLACE, PRESSURE WILL
BUILD UP FAST. EXCESSIVE PRESSURE BUILT UP,
BY CONTINUOUS ENGINE OPERATION, MUST BE
RELEASED TO A SAFE PRESSURE POINT. NEVER
PERMIT PRESSURE TO EXCEED 138 kPa (20 psi).
If the needle on the dial does not fluctuate, raise
the engine rpm a few times. If an abnormal amount
of coolant or steam emits from the tailpipe, it may
indicate a coolant leak caused by a faulty head gas-
ket, cracked engine block, or cracked cylinder head.
There may be internal leaks that can be deter-
mined by removing the oil dipstick. If water globules
appear intermixed with the oil it will indicate an
internal leak in the engine. If there is an internal
leak, the engine must be disassembled for repair.
DIAGNOSIS AND TESTING - COOLING SYSTEM
FLOW CHECK
To determine whether coolant is flowing through
the cooling system, use one of the following proce-
dures:
PREFERRED METHOD
WARNING: DO NOT REMOVE THE COOLING SYS-
TEM PRESSURE CAP OR ANY HOSE WITH THE
SYSTEM HOT AND UNDER PRESSURE BECAUSE
SERIOUS BURNS FROM COOLANT CAN OCCUR.
²Remove pressure cap when engine is cold.
Remove small amount of coolant. Idle engine until
thermostat opens. You should observe coolant flow
while looking down the filler neck. Once flow is
detected install the pressure cap. Replace removed
coolant into coolant recovery container.
ALTERNATIVE METHOD
²If engine is cold, idle engine until normal oper-
ating temperature is reached. Feel the upper radiator
hose. If it is hot, coolant is circulating.
Fig. 3 Hose Clamp Tool
1 - HOSE CLAMP TOOL 6094
2 - HOSE CLAMP
Fig. 4 Pressure Testing
RSCOOLING7-3
COOLING (Continued)
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ENGINE
DIAGNOSIS AND TESTING - ENGINE COOLING
SYSTEM
Establish what driving condition caused the cooling
system complaint. The problem may be caused by an
abnormal load on the system such as the following:
prolonged idle, very high ambient temperature, slight
tail wind at idle, slow traffic speed, traffic jam, high
speed, steep grade.
DRIVING TECHNIQUES
To avoid overheating the cooling system:
(1) Idle with A/C off when temperature gauge is at
end of normal range.
(2) Do not increase engine speed for more air flow
and coolant flow because the electric motor fan sys-
tems are not responsive to engine RPM. The added
cooling from higher coolant flow rate is more than
offset by increased heat rejection (engine heat added
to coolant).
TRAILER TOWING
Consult the owner's manual under Trailer Towing
and do not exceed specified limits.
VISUAL INSPECTION
If the cooling system problem is not caused by a
driving condition, perform a visual inspection to
determine if there was a recent service or accident
repair, including the following:
²Loose/damaged water pump drive belt
²Incorrect cooling system refilling (trapped air or
low level)
²Brakes possibly dragging
²Damaged hoses
²Loose/damaged hose clamps
²Damaged/incorrect engine thermostat
²Damaged cooling fan motor, fan blade and fan
shroud
²Damaged head gasket
²Damaged water pump
²Damaged radiator
²Damaged coolant recovery system
²Damaged heater core
²Open/shorted electrical circuits
If the visual inspection reveals none of the above
as cause for a cooling system complaint, refer to the
following diagnostic charts.
COOLING SYSTEM DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
PRESSURE CAP IS BLOWING
OFF STEAM AND/OR COOLANT.
TEMPERATURE GAUGE READING
MAY BE ABOVE NORMAL BUT
NOT HIGH. COOLANT LEVEL MAY
BE HIGH IN COOLANT RESERVE/
OVERFLOW TANK.1. Pressure relief valve in radiator
cap is defective, or was not
properly seated.1. Check condition of radiator cap
and cap seal. (Refer to 7 -
COOLING/ENGINE/RADIATOR
PRESSURE CAP - DIAGNOSIS
AND TESTING) Replace cap as
necessary.
2. Incorrect cap was installed. 2. Replace cap as necessary.
3. Incorrect coolant mixture. 3. Check concentration level of the
coolant. (Refer to 7 - COOLING/
ENGINE/COOLANT - DIAGNOSIS
AND TESTING) Adjust the ethylene
glycol-to-water ratio as required.
COOLANT LOSS TO THE
GROUND WITHOUT PRESSURE
CAP BLOWOFF. GAUGE IS
READING HIGH OR HOT.1. Coolant leaks in radiator, cooling
system hoses, water pump or
engine.1. Pressure test and repair as
necessary. (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING)
RSENGINE7-15
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(6) Fill cooling system. (Refer to 7 - COOLING -
STANDARD PROCEDURE)
ENGINE COOLANT
THERMOSTAT
DESCRIPTION
The engine cooling thermostats are a wax pellet
driven, reverse poppet choke type. The thermostat is
mounted in a housing on the coolant outlet of the
engine (Fig. 8) or (Fig. 10).
OPERATION
The engine cooling thermostat is a wax pellet
driven, reverse poppet choke type. The thermostat is
designed to provide the fastest warm up possible by
preventing leakage through it and to guarantee a
minimum engine operating temperature of 88 to
93ÉC (192 to 199ÉF). The thermostat also will auto-
matically reach wide open so it will not restrict flow
to the radiator as temperature of the coolant rises in
hot weather to around 104ÉC (220ÉF). Above this
temperature the coolant temperature is controlled by
the radiator, fan, and ambient temperature, not the
thermostat.
The thermostat is operated by a wax filled con-
tainer (pellet) which is sealed. When heated coolantreaches a predetermined temperature, the wax
expands enough to overcome the closing spring and
water pump pressure, which forces the valve to open.
DIAGNOSIS AND TESTING - ENGINE COOLANT
THERMOSTAT
The thermostat is operated by a wax filled cham-
ber (pellet) which is sealed. When heated coolant
reaches a predetermined temperature the wax pellet
expands enough to overcome the closing spring and
water pump pressure, which forces the valve to open.
Coolant leakage into the pellet will cause a thermo-
stat to fail open. Do not attempt to free up a thermo-
stat with a screwdriver.
Thermostat diagnostics is included in powertrain
control module's (PCM) programing for on-board
diagnosis. The malfunction indicator light (MIL) will
illuminate and a diagnostic trouble code (DTC) will
be set when an ªopen too soonº condition occurs. Do
not change a thermostat for lack of heater perfor-
mance or temperature gauge position, unless a DTC
is present. For other probable causes, (Refer to 7 -
COOLING/ENGINE - DIAGNOSIS AND TESTING).
Thermostat failing shut is the normal long term
mode of failure, and normally, only on high mileage
vehicles. The temperature gauge will indicate this
(Refer to 7 - COOLING/ENGINE - DIAGNOSIS AND
TESTING).
ENGINE COOLANT
THERMOSTAT - 2.4L
REMOVAL
(1) Drain cooling system below the thermostat
level. (Refer to 7 - COOLING - STANDARD PROCE-
DURE)
(2) Remove radiator upper hose from the coolant
outlet housing (Fig. 7).
(3) Remove coolant outlet housing bolts and hous-
ing (Fig. 8).
(4) Remove thermostat. Discard gasket and clean
both gasket sealing surfaces.
INSTALLATION
(1) Place a new gasket (dipped in clean water) on
the coolant outlet connector surface. Position thermo-
stat with air bleed at the 12 o'clock position in ther-
mostat housing (Fig. 8).
(2) Position the coolant outlet connector and gas-
ket over the thermostat, making sure thermostat is
seated in the thermostat housing.
(3) Position outlet connector to thermostat housing
and install bolts (Fig. 8). Tighten bolts to 28 N´m
(250 in. lbs.).
Fig. 6 Engine Coolant Temperature Sensor
1 - ENGINE COOLANT TEMPERATURE SENSOR
2 - CONNECTOR - ENGINE COOLANT SENSOR
3 - FITTING - HEATER SUPPLY
RSENGINE7-23
ENGINE COOLANT TEMPERATURE SENSOR - 3.3/3.8L (Continued)
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(4) Install the radiator upper hose to coolant outlet
housing (Fig. 7).
(5) Refill the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
ENGINE COOLANT
THERMOSTAT - 3.3/3.8L
REMOVAL
(1) Drain cooling system down below the thermo-
stat level. (Refer to 7 - COOLING - STANDARD
PROCEDURE)
(2) Remove radiator upper hose from coolant outlet
connector (Fig. 9).
(3) Remove coolant outlet connector bolts and con-
nector (Fig. 10).
(4) Remove thermostat from outlet connector.
(5) Discard gasket and clean both gasket sealing
surfaces.
INSTALLATION
(1) To ensure proper seating of replacement ther-
mostat, carefully remove the bulged metal from the
wall of the outlet connector recess that was created
during the staking procedure that held the OEM
thermostat in place (Fig. 11). It is not necessary to
restake the replacement thermostat into the connec-
tor.
(2) Position thermostat to coolant outlet connector.
Align the two locating notches on thermostat to the
connector (Fig. 12). This position will ensure proper
location of the thermostat air bleed.
Fig. 7 RADIATOR HOSES TO ENGINE - 2.4L
1 - UPPER HOSE
2 - LOWER HOSE
Fig. 8 Thermostat and Outlet Connector - 2.4L
Engine
1 - THERMOSTAT
2 - GASKET
3 - COOLANT OUTLET CONNECTOR
4 - BOLT
Fig. 9 RADIATOR HOSES TO ENGINE - 3.3/3.8L
1 - UPPER HOSE
2 - LOWER HOSE
7 - 24 ENGINERS
ENGINE COOLANT THERMOSTAT - 2.4L (Continued)
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(3) Position a new gasket over the thermostat and
connector making sure thermostat is in proper posi-
tion and in the recess provided.
(4) Install thermostat and connector assembly to
the intake manifold (Fig. 10). Tighten bolts to 28
N´m (250 in. lbs.).
(5) Install the radiator upper hose to coolant outlet
connector (Fig. 9).
(6) Refill the cooling system to the proper level.
(Refer to 7 - COOLING - STANDARD PROCEDURE)
RADIATOR
DESCRIPTION
The radiator is a cross-flow type (horizontal tubes)
with design features that provide greater strength
along with sufficient heat transfer capabilities to
keep the engine satisfactorily cooled. The radiator
has plastic side tanks and aluminum cooling tubes.
OPERATION
The radiator functions as a heat exchanger, using
air flow across the exterior of the radiator tubes. This
heat is then transferred from the coolant and into
the passing air.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove radiator upper crossmember support.
(Refer to 23 - BODY/EXTERIOR/GRILLE OPENING
REINFORCEMENT - REMOVAL)
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK PLUG OR THE RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
(3) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(4) Remove the radiator fans. (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - REMOVAL)
(5) Disconnect coolant reserve/recovery hose.
Fig. 10 THERMOSTAT - 3.3/3.8L ENGINE
1 - COOLANT OUTLET CONNECTOR
2 - BOLT
3 - THERMOSTAT
4 - GASKET
Fig. 11 Connector Staking Material Removal
1-STAKE
2 - OUTLET CONNECTOR
Fig. 12 Thermostat Position In Outlet Connector
1 - LOCATING NOTCH
2 - THERMOSTAT
3 - COOLANT OUTLET CONNECTOR
RSENGINE7-25
ENGINE COOLANT THERMOSTAT - 3.3/3.8L (Continued)
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RADIATOR DRAINCOCK
REMOVAL
CAUTION: Use of pliers on draincock is not recom-
mended. Damage may occur to radiator or drain-
cock.
NOTE: It is not necessary to remove draincock dur-
ing a routine coolant drain.
(1) Drain the cooling system. (Refer to 7 - COOL-
ING - STANDARD PROCEDURE)
(2) Open the draincock by turning it counterclock-
wise until it stops.
(3) Turn the draincock back (clockwise) 1/8 turn.
(4) Pull the draincock (Fig. 16) from the radiator
tank.
INSTALLATION
(1) Align draincock stem to radiator tank opening.
(2) Push draincock into the radiator tank opening.
(3) Tighten the draincock by turning clockwise
until it stops.
(4) Fill the cooling system. (Refer to 7 - COOLING
- STANDARD PROCEDURE)
RADIATOR PRESSURE CAP
DESCRIPTION
The cooling system pressure cap is located on the
radiator. The cap construction includes; stainless
steel swivel top, rubber seals, and retainer, main
spring, and a spring loaded valve (Fig. 17).
OPERATION
The cooling system is equipped with a pressure cap
that releases excessive pressure; maintaining a range
of 97-124 kPa (14-18 psi).
The cooling system will operate at higher than
atmospheric pressure. The higher pressure raises the
coolant boiling point thus, allowing increased radia-
tor cooling capacity.
There is also a vent valve in the center of the cap.
This valve also opens when coolant is cooling and
contracting, allowing the coolant to return to cooling
system from coolant reserve system tank by vacuum
through a connecting hose.If valve is stuck shut,
or the coolant recovery hose is pinched, the
radiator hoses will be collapsed on cool down.
Clean the vent valve (Fig. 17) and inspect cool-
ant recovery hose routing, to ensure proper
sealing when boiling point is reached.
The gasket in the cap seals the filler neck, so that
vacuum can be maintained, allowing coolant to be
drawn back into the radiator from the reserve tank.
If the gasket is dirty or damaged, a vacuum
may not be achieved, resulting is loss of coolant
and eventual overheating due to low coolant
level in radiator and engine.
Fig. 16 Draincock
1 - RADIATOR TANK
2 - DRAINCOCK
Fig. 17 Cooling System Pressure Cap Filler Neck
1 - OVERFLOW NIPPLE
2 - MAIN SPRING
3 - GASKET RETAINER
4 - STAINLESS-STEEL SWIVEL TOP
5 - RUBBER SEALS
6 - VENT VALVE
7 - RADIATOR
8 - FILLER NECK
RSENGINE7-27
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DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - COOLING SYSTEM
PRESSURE CAP TESTING
Dip the pressure cap in water. Clean any deposits
off the vent valve or its seat and apply cap to end of
the Pressure Cap Test Adaptor that is included with
the Cooling System Tester 7700 (Fig. 18). Working
the plunger, 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 pressure cap.
CAUTION: The Cooling System Tester Tool is very
sensitive to small air leaks that will not cause cool-
ing system problems. A pressure cap that does not
have a history of coolant loss should not be
replaced just because it leaks slowly when tested
with this tool. Add water to the tool. Turn tool
upside down and recheck pressure cap to confirm
that cap is bad.
If the pressure cap tests properly while positioned
on Cooling System Tester (Fig. 18), but will not hold
pressure or vacuum when positioned on the filler
neck. Inspect the filler neck and cap top gasket for
irregularities that may prevent the cap from sealing
properly.
DIAGNOSIS AND TESTING - RADIATOR CAP
TO FILLER NECK SEAL
The pressure cap upper gasket (seal) pressure
relief can be checked by removing the overflow hose
at the radiator filler neck nipple (Fig. 19). Attach the
Radiator Pressure Tool to the filler neck nipple and
pump air into the radiator. Pressure cap upper gas-ket should relieve at 69-124 kPa (10-18 psi) and hold
pressure at 55 kPa (8 psi) minimum.
WARNING: THE WARNING WORDS ªDO NOT OPEN
HOTº ON THE RADIATOR PRESSURE CAP IS A
SAFETY PRECAUTION. WHEN HOT, PRESSURE
BUILDS UP IN COOLING SYSTEM. TO PREVENT
SCALDING OR INJURY, THE RADIATOR CAP
SHOULD NOT BE REMOVED WHILE THE SYSTEM
IS HOT OR UNDER PRESSURE.
There is no need to remove the radiator cap at any
timeexceptfor the following purposes:
(1) Check and adjust coolant freeze point.
(2) Refill system with new coolant.
(3) Conducting service procedures.
(4) Checking for vacuum leaks.
WARNING: IF VEHICLE HAS BEEN RUN RECENTLY,
WAIT 15 MINUTES BEFORE REMOVING CAP. THEN
PLACE A SHOP TOWEL OVER THE CAP AND WITH-
OUT PUSHING DOWN ROTATE COUNTERCLOCK-
WISE TO THE FIRST STOP. ALLOW FLUIDS TO
ESCAPE THROUGH THE OVERFLOW TUBE AND
WHEN THE SYSTEM STOPS PUSHING COOLANT
AND STEAM INTO THE CRS TANK AND PRESSURE
DROPS PUSH DOWN AND REMOVE THE CAP COM-
PLETELY. SQUEEZING THE RADIATOR INLET HOSE
WITH A SHOP TOWEL (TO CHECK PRESSURE)
BEFORE AND AFTER TURNING TO THE FIRST
STOP IS RECOMMENDED.
Fig. 18 Testing Cooling System Pressure Cap
1 - PRESSURE CAP
2 - PRESSURE TESTER
Fig. 19 Radiator Pressure Cap Filler Neck
1 - OVERFLOW NIPPLE
2 - MAIN SPRING
3 - GASKET RETAINER
4 - STAINLESS-STEEL SWIVEL TOP
5 - RUBBER SEALS
6 - VENT VALVE
7 - RADIATOR
8 - FILLER NECK
7 - 28 ENGINERS
RADIATOR PRESSURE CAP (Continued)
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