ABS CHRYSLER VOYAGER 2001 Service Manual

REMOVAL - ICU
(1) Disconnect the negative (ground) cable from
the battery and isolate cable.
(2) Remove the battery shield.
(3) Remove the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - REMOVAL).
(4) Disconnect the vacuum hose connector at the
tank built into the battery tray.
(5) Remove the screw securing the engine coolant
filler neck to the battery tray.
(6) Remove the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - REMOVAL).
(7) Using a brake pedal depressor, move and lock
the brake pedal to a position past the first inch of
pedal travel.This will prevent brake fluid from
draining out of the master cylinder once the
brake tubes are removed from the HCU.
CAUTION: Do not apply a 12±volt power source to
any terminals of the 24-way CAB connector when
disconnected.
(8) Disconnect the wiring harness connector from
the speed control servo.
(9) Remove the speed control servo mounting nuts
and move the servo out of the way.
(10) Disconnect the 24±way connector from the
CAB. To disconnect the 24±way connector, grasp the
lock on the 24±way connector and pull it as far up as
possible. This will unlock the 24±way connector from
the socket on the CAB.
CAUTION: Before removing the brake tubes from
the HCU, the HCU must be thoroughly cleaned. This
must be done to prevent dirt particles from falling
into the ports of HCU or entering the brake tubes.
(11) Thoroughly clean all surfaces of the ICU and
brake tube nuts. Use only a solvent such as Mopart
Brake Parts Cleaner or equivalent to clean the ICU.
(12) Remove the brake tubes (4) from the outlet
ports on the HCU (Fig. 9).
(13) Remove the primary and secondary brake
tubes from the inlet ports on the HCU (Fig. 9).
(14) Center and prop the steering wheel.
(15) Remove the silencer panel under the instru-
ment panel, below the steering column.
(16) Remove the pinch bolt and disconnect the
steering shaft coupling.
(17) Remove the two clips securing silencer to dash
seal (Fig. 10).
(18) Remove the three screws securing the dash
seal (Fig. 10).
(19) Remove the 3 bolts attaching the ICU to its
mounting bracket (Fig. 11).
(20) Remove ICU from the vehicle through engine
compartment.(21) If required, to separating the CAB from the
HCU, (Refer to 5 - BRAKES - ABS/HYDRAULIC/ME-
CHANICAL/ICU (INTEGRATED CONTROL UNIT) -
DISASSEMBLY).
Fig. 9 BRAKE TUBE NUTS AT ICU
1 - PRIMARY BRAKE TUBE
2 - SECONDARY BRAKE TUBE
3 - CHASSIS BRAKE TUBES
Fig. 10 LOWER COUPLING AND DASH SEAL
1 - COUPLING
2 - DASH SEAL
3 - SILENCER
4 - MOUNTING SCREWS
5 - RETAINING CLIPS
6 - DASH
5 - 76 BRAKES - ABSRS
ICU (INTEGRATED CONTROL UNIT) (Continued)

DISASSEMBLY - ICU
(1) Remove the ICU from the vehicle. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ICU (INTE-
GRATED CONTROL UNIT) - REMOVAL)
(2) Disconnect the pump/motor wiring harness
(Fig. 12) from the CAB.
(3) Remove the 4 bolts (Fig. 13) attaching the CAB
to the HCU.
(4) Remove the CAB from the HCU (Fig. 14).
ASSEMBLY - ICU
(1) Install the CAB (Fig. 14) on the HCU.(2) Install the 4 bolts mounting the CAB (Fig. 13)
to the HCU. Tighten the CAB mounting bolts to a
torque of 2 N´m (17 in. lbs.).
(3) Plug the pump/motor wiring harness into the
CAB.
(4) Install the ICU in the vehicle and bleed the
base and ABS hydraulic systems. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ICU (INTE-
GRATED CONTROL UNIT) - INSTALLATION)
INSTALLATION - ICU
(1) Place the ICU in its bracket below the master
cylinder. Start the upper mounting bolt to hold it in
place.
Fig. 11 ICU MOUNTING BOLTS
1 - ICU MOUNTING BOLTS
2 - COUPLER
Fig. 12 INTEGRATED CONTROL UNIT (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
Fig. 13 (TYPICAL) CAB Attaching Bolts
1 - MOUNTING BOLTS
2 - CAB
3 - HCU VALVE BLOCK
Fig. 14 (TYPICAL) Remove/Install CAB
1 - CAB
2 - HCU VALVES
3 - HCU VALVE BLOCK
RSBRAKES - ABS5-77
ICU (INTEGRATED CONTROL UNIT) (Continued)

(2) Inside the vehicle, install the remaining 2
mounting bolts attaching the ICU to the mounting
bracket (Fig. 11). Tighten all 3 mounting bolts to a
torque of 11 N´m (97 in. lbs.).
(3) Install the dash seal and three mounting
screws (Fig. 10).
(4) Install the silencer on top of the dash seal (Fig.
10).
(5) Connect the steering shaft coupling and install
the pinch bolt (Fig. 10). Tighten the pinch bolt to 28
N´m (250 in. lbs.).
(6) Install the silencer panel below the steering
column under the instrument panel.
(7) Remove the steering wheel holder.
CAUTION: Because of the flexible section in the pri-
mary and secondary brake tubes, the brake tubes
must be held in proper orientation when tightened
and torqued. These tubes must not contact each
other or other vehicle components when installed.
Also, after the brake tubes are installed on the HCU,
ensure all spacer clips are reinstalled on the brake
tubes.
(8) Install the primary and secondary brake tubes
into their correct port locations on the HCU valve
block (Fig. 9). Tighten the tube nuts to a torque of 17
N´m (145 in. lbs.).
CAUTION: When installing the chassis brake tubes
on the HCU valve block, they must be located cor-
rectly in the valve block to ensure proper ABS oper-
ation.
NOTE: The chassis brake tube attachment locations
to the HCU, are marked on the bottom of the CAB.
(9) Install the (4) chassis brake tubes into their
correct port locations on the HCU valve block as
shown (Fig. 9). Tighten the tube nuts to a torque of
17 N´m (145 in. lbs.).NOTE: Before installing the 24±way connector in
the CAB be sure the seal is properly installed in the
connector.
(10) Install the 24±way connector on the CAB by,
first, positioning the 24±way connector in the socket
of the CAB and carefully pushing it down as far as
possible. Once connector is fully seated by hand into
the CAB socket, push down on connector lock. This
will pull the connector into the socket of the CAB
and lock it in the installed position.
(11) Install any routing clips on the brake tubes.
(12) Remove the brake pedal holder.
(13) Install the speed control servo with its mount-
ing nuts.
(14) Connect the wiring harness to the speed con-
trol servo.
(15) Install the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - INSTALLA-
TION).
(16) Install the screw securing the coolant filler
neck to the battery tray.
(17) Reconnect the vacuum hose connector at the
tank built into the battery tray.
(18) Install the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - INSTALLA-
TION).
(19) Install the battery shield.
(20) Remove the brake pedal holder.
(21) Connect negative cable back on negative post
of the battery.
(22) Bleed the Base and ABS brake hydraulic sys-
tems (Refer to 5 - BRAKES - STANDARD PROCE-
DURE).
(23) Road test vehicle to ensure proper operation
of the base and antilock brake systems.
5 - 78 BRAKES - ABSRS
ICU (INTEGRATED CONTROL UNIT) (Continued)

BRAKES
TABLE OF CONTENTS
page page
BRAKES - BASE........................... 1BRAKES - ABS........................... 10
BRAKES - BASE
TABLE OF CONTENTS
page page
BRAKES - BASE
DESCRIPTION............................1
HYDRAULIC/MECHANICAL
DESCRIPTION............................1
FLUID
STANDARD PROCEDURE...................1
BRAKE FLUID LEVEL CHECKING...........1
MASTER CYLINDER - RHD
DESCRIPTION............................2
REMOVAL...............................2
INSTALLATION............................3
PEDAL TORQUE SHAFT
REMOVAL...............................3
INSTALLATION............................4POWER BRAKE BOOSTER - RHD
REMOVAL...............................4
INSTALLATION............................6
ROTORS
SPECIFICATIONS.........................8
PARKING BRAKE
DESCRIPTION............................8
CABLES - PARKING BRAKE
REMOVAL...............................8
INSTALLATION............................8
LEVER - PARKING BRAKE
REMOVAL...............................8
INSTALLATION............................9
BRAKES - BASE
DESCRIPTION - BASE BRAKES
Four-Wheel Disc Antilock Brakes are standard on
all models.
HYDRAULIC/MECHANICAL
DESCRIPTION - DISC BRAKES
All vehicles are equipped with Four-Wheel-Disc
brakes. Both 15º (BRE) and 16º (BR3) disc/disc brake
systems are available. The disc brakes are manufac-
tured by Continental Teves. The BR3 system is stan-
dard equipment on all-wheel drive and all right-hand
drive models. It is optional on other models.
The BR3 system features larger, externally vented
front brake rotors.
Although there are different disc/disc systems, they
are serviced using the same service procedures. Some
specifications differ.
FLUID
STANDARD PROCEDURE - BRAKE FLUID
LEVEL CHECKING
Right hand drive vehicles feature a brake fluid res-
ervoir with the same markings as left hand drive res-
ervoirs.
Check master cylinder reservoir fluid level a mini-
mum of twice annually.
Fluid reservoirs are marked with the words FULL
and ADD to indicate proper brake fluid fill level of
the master cylinder.
If necessary, add brake fluid to bring the level to
the bottom of the FULL mark on the side of the mas-
ter cylinder fluid reservoir.
Use only Mopartbrake fluid or equivalent from a
sealed container. Brake fluid must conform to DOT 3
specifications (DOT 4 or DOT 4+ are acceptable).
DO NOTuse brake fluid with a lower boiling
point, as brake failure could result during prolonged
hard braking.
RGBRAKES5a-1

CAUTION: A seal on the rear of the master cylinder
is used to create the seal for holding vacuum in the
power brake vacuum booster. The vacuum seal on
the master cylinder MUST be replaced whenever the
master cylinder is removed from the power brake
vacuum booster.
(12) Remove vacuum seal located on the mounting
flange of the master cylinder. The vacuum seal is
removed from master cylinder bycarefullypulling it
off the rear of master cylinder.Do not attempt to
pry the seal off the master cylinder by inserting
a sharp tool between seal and master cylinder
casting.
INSTALLATION
CAUTION: Different types of master cylinders are
used on this vehicle depending on brake options. If
a new master cylinder is being installed, be sure it
is the correct master cylinder for the type of brake
system the vehicle is equipped with.
CAUTION: When replacing the master cylinder on a
vehicle, a NEW vacuum seal MUST be installed on
the master cylinder.
(1) Install a NEW vacuum seal on master cylinder
making sure seal fits squarely in groove of master
cylinder casting.
(2) Position master cylinder on studs of power
brake booster, aligning booster push rod with master
cylinder piston.
(3) Install the two master cylinder mounting nuts
(Fig. 2). Tighten both mounting nuts to a torque of
25 N´m (225 in. lbs.).
CAUTION: When tightening the primary and sec-
ondary brake tube nuts at master cylinder, be sure
brake tubes do not contact any other components
within the vehicle and that there is slack in the flex-
ible sections of the tubes. This is required due to
the movement between the ABS ICU and the master
cylinder while the vehicle is in motion.
(4) Connect primary and secondary brake tubes to
master cylinder primary and secondary ports (Fig. 2).
Brake tubes must be held securely when tightened to
control orientation of flex section. Tighten tube nuts
to a torque of 17 N´m (145 in. lbs.).
(5) Install wiring harness connector to brake fluid
level switch mounted in brake fluid reservoir (Fig. 1).
(6) Install battery, clamp and nut.
(7) Install battery shield.
(8) Connect positive battery terminal.
(9) Connect negative battery terminal.(10) Fill master cylinder with clean, fresh Mopart
Brake Fluid or equivalent.
(11) Road test vehicle to ensure proper operation of
brakes.
PEDAL TORQUE SHAFT
REMOVAL
(1) Remove the instrument panel. (Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL ASSEMBLY - REMOVAL)
(2) Remove the HVAC housing. (Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - REMOVAL)
(3) Remove the retaining clip at the torque shaft
end of the brake pedal-to-torque shaft link. Remove
the link from the torque shaft. Discard the retaining
clip. It is not to be reused. Replace with a new clip
when reassembled.
(4) Locate the booster input rod-to-brake pedal
torque shaft connection and remove the retaining clip
(Fig. 3). Discard the retaining clip. It is not to be
reused. Replace with a new clip when reassembled.
(5) Remove the four (4) brake booster retaining
nuts from inside the passenger compartment (Fig. 4).
(6) Remove the retaining nut from the brake
booster bracket located above the booster in the
engine compartment (Fig. 4).
(7) Remove the power brake booster bracket.
(8) Rotate the pedal torque shaft and remove it out
the left side of the vehicle.
Fig. 3 POWER BRAKE BOOSTER BRACKET
1 - BOOSTER BRACKET
2 - PEDAL TORQUE SHAFT
3 - RETAINING CLIP
4 - BOOSTER MOUNTING NUTS
RGBRAKES - BASE5a-3
MASTER CYLINDER - RHD (Continued)

BRAKES - ABS
TABLE OF CONTENTS
page page
BRAKES - ABS
DESCRIPTION...........................10
ICU (INTEGRATED CONTROL UNIT) - RHD
REMOVAL..............................10DISASSEMBLY...........................11
ASSEMBLY.............................12
INSTALLATION...........................13
BRAKES - ABS
DESCRIPTION - ANTILOCK BRAKE SYSTEM
Four-wheel disc antilock brakes are standard on all
models. The Mark 20e antilock brake system is used
on all models. Depending on whether the vehicle is a
left-hand drive (LHD) or right-hand drive (RHD)
model, the integrated control unit (ICU) is located in
one of two locations. On LHD models, the ICU is
mounted above the front suspension cradle/cross-
member below the master cylinder. On RHD models,
the ICU is located behind the front suspension cra-
dle/crossmember on the left side of the vehicle.
ICU (INTEGRATED CONTROL
UNIT) - RHD
REMOVAL - RHD
NOTE: Before proceeding, review all WARNINGS
AND CAUTIONS.
(1) Disconnect the negative (ground) cable from
the battery and isolate cable.
(2) Using a brake pedal depressor, move and lock
the brake pedal to a position past the first inch of
pedal travel.This will prevent brake fluid from
draining out of the master cylinder when the
brake tubes are removed from the HCU.
(3) Raise vehicle. See Hoisting in the Lubrication
And Maintenance.
(4) Remove the routing clip attaching the ICU wir-
ing harness to the ICU mounting bracket (Fig. 1).CAUTION: Do not apply a 12 volt power source to
any terminals of the HCU connector when discon-
nected.
(5) Remove the 24-way connector (Fig. 1) from the
CAB. The 24-way connector is removed from the CAB
using the following procedure. Grasp the lock on the
24-way connector (Fig. 1) and pull it as far out as
possible (Fig. 2). This will raise and unlock the
24-way connector from the socket on the CAB.
Fig. 1 CAB 24-Way Connector
1 - CAB WIRING HARNESS
2 - 24±WAY CONNECTOR
3 - FLOOR PAN
4 - HCU
5 - CAB
6 - HCU MOUNTING BRACKET
7 - CONNECTOR LOCK
5a - 10 BRAKES - ABSRG

CAUTION: Before removing the brake tubes from
the HCU, the HCU must be thoroughly cleaned. This
must be done to prevent dirt particles from falling
into the ports of HCU or entering the brake tubes.
(6) Thoroughly clean all surfaces of the HCU, and
all brake tube nuts located on the HCU. Use only a
solvent such as Mopar Brake Parts Cleaner or an
equivalent to clean the HCU.
(7) Remove the brake tubes (6) from the inlet and
outlet ports on the HCU. (Fig. 3).
(8) Remove the 3 bolts (Fig. 4) attaching the ICU
mounting bracket to the front suspension crossmem-
ber.
(9) Remove ICU and the mounting bracket as a
unit from the vehicle.
(10) Remove the 3 bolts (Fig. 5) mounting the ICU
to the mounting bracket. Separate the ICU from the
mounting bracket.
(11) For the procedure on separating and attaching
the CAB to the HCU, refer to DISASSEMBLY.
DISASSEMBLY
(1) Remove the ICU from the vehicle. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ICU (INTE-
GRATED CONTROL UNIT) - REMOVAL)
(2) Disconnect the pump/motor wiring harness
from the CAB (Fig. 6).
Fig. 2 Unlocked 24-Way CAB Connector
1 - HCU
2 - CAB
3 - 24±WAY CONNECTOR
4 - CONNECTOR LOCK (UNLOCKED)
Fig. 3 Brake Tube Connections To HCU
1 - LEFT REAR WHEEL BRAKE TUBE
2 - SECONDARY BRAKE TUBE FROM MASTER CYLINDER
3 - LEFT FRONT WHEEL BRAKE TUBE
4 - CAB
5 - RIGHT REAR WHEEL BRAKE TUBE
6 - HCU MOUNTING BRACKET
7 - BRAKE TUBE TO HCU CONNECTION LOCATION LEGEND
8 - RIGHT FRONT WHEEL BRAKE TUBE
9 - PRIMARY BRAKE TUBE FROM MASTER CYLINDER
Fig. 4 ICU To Suspension Cradle Mounting Bolts
1 - HCU MOUNTING BRACKET BOLTS
2 - HCU MOUNTING BRACKET BOLT
3 - CAB
4 - HCU MOUNTING BRACKET
5 - HCU
RGBRAKES - ABS5a-11
ICU (INTEGRATED CONTROL UNIT) - RHD (Continued)

(3) Remove the 4 bolts (Fig. 7) attaching the CAB
to the HCU.
(4) Remove the CAB from the HCU (Fig. 8).ASSEMBLY
(1) Install the CAB (Fig. 8) on the HCU.
(2) Install the 4 bolts mounting the CAB (Fig. 7) to
the HCU. Tighten the CAB mounting bolts to a
torque of 2 N´m (17 in. lbs.).
(3) Plug the pump/motor wiring harness into the
CAB.
(4) Install the ICU in the vehicle and bleed the
base and ABS hydraulic systems. (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/ICU (INTE-
GRATED CONTROL UNIT) - INSTALLATION)
Fig. 5 ICU Mounting Bolts
1 - HCU
2 - HCU MOUNTING BOLTS
3 - HCU MOUNTING BRACKET
Fig. 6 INTEGRATED CONTROL UNIT (ICU)
1 - PUMP/MOTOR
2 - HCU
3 - PUMP/MOTOR CONNECTOR
4 - CAB
Fig. 7 (TYPICAL) CAB Attaching Bolts
1 - MOUNTING BOLTS
2 - CAB
3 - HCU VALVE BLOCK
Fig. 8 (TYPICAL) Remove/Install CAB
1 - CAB
2 - HCU VALVES
3 - HCU VALVE BLOCK
5a - 12 BRAKES - ABSRG
ICU (INTEGRATED CONTROL UNIT) - RHD (Continued)

INSTALLATION - RHD
(1) Install the ICU on the mounting bracket (Fig.
5). Install the 3 bolts (Fig. 5) attaching the ICU to
the mounting bracket. Tighten the 3 mounting bolts
to a torque of 11 N´m (97 in. lbs.).
CAUTION: The ICU mounting bracket to front sus-
pension cradle mounting bolts have a unique corro-
sion protection coating and a special aluminum
washer. For this reason, only the original, or origi-
nal equipment Mopar replacement bolts can be
used to mount the ICU bracket to the front suspen-
sion crossmember.
(2) Install the ICU and its mounting bracket as an
assembly on the front suspension crossmember.
Install the 3 bolts attaching the ICU bracket to the
crossmember (Fig. 4). Tighten the 3 mounting bolts
to a torque of 28 N´m (250 in. lbs.).
CAUTION: Because of the flexible section in the pri-
mary and secondary brake tubes, and the brake
tubes between the HCU and the proportioning
valve, the brake tubes must be held in proper ori-
entation when tightened and torqued. These tubes
must not contact each other or other vehicle com-
ponents when installed. Also, after the brake tubes
are installed on the HCU, ensure all spacer clips are
reinstalled on the brake tubes.
CAUTION: When installing the chassis brake tubes
on the HCU valve block, they must be located cor-
rectly in the valve block to ensure proper ABS oper-
ation. Refer to (Fig. 3) for the correct chassis brake
tube locations.
NOTE: The chassis brake tube attachment locations
to the HCU, are marked on the bottom of the ICU
mounting bracket.
(3) Install the 6 chassis brake tubes into their cor-
rect port locations on the HCU valve block as shown
in (Fig. 3). Tighten the tube nuts to a torque of 17
N´m (145 in. lbs.).
NOTE: Before installing the 24-way connector in the
CAB be sure the seal is properly installed in the
connector.(4) Install the 24-way connector (Fig. 1) on the
CAB using the following procedure. Position the
24-way connector in the socket of the CAB and care-
fully push it down as far as possible. When connector
is fully seated by hand into the CAB socket, push in
the connector lock (Fig. 2). This will pull the connec-
tor into the socket of the CAB and lock it in the
installed position.
NOTE: The CAB wiring harness must be clipped to
the ICU mounting bracket. This will ensure the wir-
ing harness is properly routed and does not contact
the brake tubes or the body of the vehicle.
(5) Clip the cab wiring harness (Fig. 1) to the ICU
mounting bracket.
(6) Install the routing clips (Fig. 9) on the brake
tubes.
(7) Lower the vehicle.
(8) Connect negative cable back on negative post of
the battery.
(9) Bleed the base and ABS hydraulic systems.
Refer to ANTILOCK BRAKE SYSTEM BLEEDING.
(10) Road test vehicle to ensure proper operation
of the base and antilock brake systems.
Fig. 9 Brake Tube Routing Clips
1 - ROUTING CLIP
2 - HCU
3 - BRAKE TUBES
4 - ROUTING CLIP
RGBRAKES - ABS5a-13
ICU (INTEGRATED CONTROL UNIT) - RHD (Continued)

ENGINE
TABLE OF CONTENTS
page page
COOLANT
DESCRIPTION...........................14
DIAGNOSIS AND TESTING.................15
COOLANT CONCENTRATION TESTING......15
STANDARD PROCEDURE..................15
COOLANT SERVICE.....................15
ADDING ADDITIONAL COOLANT...........15
COOLANT LEVEL CHECK................16
REFILLING COOLING SYSTEM............16
DRAINING COOLING SYSTEM.............16
COOLANT RECOVERY PRESS CONTAINER
DESCRIPTION...........................17
OPERATION.............................17
REMOVAL..............................18
INSTALLATION...........................18
ENGINE COOLANT TEMP SENSOR
DESCRIPTION...........................19
OPERATION.............................19
REMOVAL..............................19
INSTALLATION...........................19
ENGINE COOLANT THERMOSTAT
DESCRIPTION...........................19
OPERATION.............................19
REMOVAL..............................19
INSTALLATION...........................20
RADIATOR
DESCRIPTION...........................20
OPERATION.............................20
REMOVAL..............................20
INSTALLATION...........................21
RADIATOR DRAINCOCK
REMOVAL..............................22INSTALLATION...........................22
WATER PUMP
DESCRIPTION...........................22
OPERATION.............................22
REMOVAL..............................22
CLEANING..............................23
INSTALLATION...........................23
RADIATOR PRESSURE CAP
DESCRIPTION...........................24
OPERATION.............................24
DIAGNOSIS AND TESTING.................25
COOLING SYSTEM PRESSURE CAP........25
PRESSURE RELIEF TEST................25
CLEANING..............................25
INSPECTION............................26
RADIATOR FAN
DESCRIPTION...........................26
OPERATION.............................26
DIAGNOSIS AND TESTING.................26
RADIATOR FAN MOTOR.................26
REMOVAL..............................27
INSTALLATION...........................27
HOSE CLAMPS
DESCRIPTION...........................27
OPERATION.............................28
RADIATOR FAN RELAY
DESCRIPTION...........................28
OPERATION.............................28
COOLANT SYSTEM HOSES
REMOVAL..............................28
INSTALLATION...........................29
COOLANT
DESCRIPTION
Coolant flows through the engine water jackets
and cylinder heads absorbing heat produced by the
engine during operation. The coolant carries heat to
the radiator and heater core. Here it is transferred to
ambient air passing through the radiator and heater
core fins.
The required ethylene-glycol (antifreeze) and water
mixture depends upon the climate and vehicle oper-
ating conditions. The recommended mixture of 50/50
ethylene-glycol and water will provide protectionagainst freezing to -37 deg. C (-35 deg. F). The anti-
freeze concentrationmust alwaysbe a minimum of
44 percent, year-round in all climates.If percentage
is lower than 44 percent, engine parts may be
eroded by cavitation, and cooling system com-
ponents may be severely damaged by corrosion.
Maximum protection against freezing is provided
with a 68 percent antifreeze concentration, which
prevents freezing down to -67.7 deg. C (-90 deg. F). A
higher percentage will freeze at a warmer tempera-
ture. Also, a higher percentage of antifreeze can
cause the engine to overheat because the specific
heat of antifreeze is lower than that of water.
7a - 14 ENGINERG