radiator cap CHRYSLER VOYAGER 1996 Service Manual

COOLING SYSTEM
CONTENTS
page page
GENERAL INFORMATION
ACCESSORY DRIVE BELTS................ 1
AUTOMATIC TRANSMISSION OIL COOLERÐ
2.4L................................. 3
COOLANT RECOVERY SYSTEM (CRS)....... 3
COOLANT.............................. 3
COOLING SYSTEM....................... 2
ENGINE BLOCK HEATER.................. 5
ENGINE THERMOSTAT.................... 3
RADIATOR PRESSURE CAP................ 4
RADIATOR............................. 3
WATER PUMPS......................... 3
DESCRIPTION AND OPERATION
COOLANT PERFORMANCE................. 6
RADIATOR HOSES AND CLAMPS........... 6
WATER PIPESÐ3.0L ENGINE.............. 6
WATER PUMPÐ3.3/3.8L ENGINES.......... 7
WATER PUMPÐ2.4L ENGINE.............. 6
WATER PUMPÐ3.0L ENGINE.............. 6
DIAGNOSIS AND TESTING
ACCESSORY DRIVE BELT.................. 7
COOLING SYSTEM DIAGNOSIS............. 8
DEAERATION.......................... 16
ELECTRIC FAN MOTOR TEST.............. 14
LOW COOLANT LEVEL AERATION.......... 15
PRESSURE TESTING RADIATOR CAP....... 15
RADIATOR CAP TO FILLER NECK SEAL
PRESSURE RELIEF CHECK.............. 15
RADIATOR COOLANT FLOW TEST.......... 14
RADIATOR FAN CONTROL................ 14
TEMPERATURE GAUGE INDICATION........ 16
TESTING COOLING SYSTEM FOR LEAKS.... 14
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE........ 16
COOLANT LEVEL SERVICE................ 16COOLANTÐADDING ADDITIONAL.......... 16
COOLING SYSTEMÐDRAINING............ 16
COOLING SYSTEMÐREFILLING........... 16
REMOVAL AND INSTALLATION
ACCESSORY DRIVE BELTSÐ2.4L.......... 23
ACCESSORY DRIVE BELTSÐ3.0L.......... 24
ACCESSORY DRIVE BELTÐ3.3/3.8L........ 24
ENGINE BLOCK HEATER................. 23
FAN MODULE.......................... 22
RADIATOR DRAINCOCK.................. 21
RADIATOR............................ 21
THERMOSTATÐ2.4L ENGINE............. 19
THERMOSTATÐ3.0L ENGINE............. 20
THERMOSTATÐ3.3/3.8L ENGINES......... 20
WATER PUMP INLET TUBEÐ2.4L ENGINE . . . 17
WATER PUMPÐ3.3/3.8L ENGINES......... 19
WATER PUMPÐ2.4L ENGINE............ 17
WATER PUMPÐ3.0L ENGINE............. 18
CLEANING AND INSPECTION
ACCESSORY DRIVE BELT................. 25
CHEMICAL CLEANING................... 25
COOLING SYSTEM CLEANING............. 25
RADIATOR PRESSURE CAP............... 25
REVERSE FLUSHING THE ENGINE......... 25
REVERSE FLUSHING THE RADIATOR....... 25
WATER PUMP......................... 24
ADJUSTMENTS
BELT TENSION CHART................... 26
BELT TENSION GAUGE METHOD........... 26
PROPER BELT TENSION................. 25
SPECIFICATIONS
COOLING SYSTEM CAPACITY............. 26
TORQUE CHART........................ 26
SPECIAL TOOLS
COOLING............................. 26
GENERAL INFORMATION
ACCESSORY DRIVE BELTS
The accessory drive system utilizes two different
style of drive belts. The conventional V-belt and the
Poly-V belt are used to drive the generator, air con-
ditioning compressor, power steering pump and waterpump. Satisfactory performance of these belts
depends on belt condition and proper belt tension.
Belt tensioning should be performed with the aid of a
Burroughs gauge Special Tool C-4162. Because of
space limitations in the engine compartment, the use
of the gauge may be restricted. Raise the vehicle on a
hoist and then remove the splash shield to gain
access to the drive belts.
NSCOOLING SYSTEM 7 - 1

COOLING SYSTEM
The cooling system has a radiator, coolant, electric fan
motor, shroud, pressure cap, thermostat, coolant reserve
system, transmission oil cooler, a water pump to circulate
the coolant, hoses, and clamps to complete the circuit.
²When Engine is cold: thermostat is closed, cool-
ing system has no flow through the radiator. The
coolant bypass flows through the engine only.
²
When Engine is warm: thermostat is open, cooling
system has bypass flow and coolant flow through radia-
tor.
Its primary purpose is to maintain engine temper-
ature in a range that will provide satisfactory engine
performance and emission levels under all expected
driving conditions. It also provides hot water (cool-
ant) for heater performance and cooling for automatic
transmission oil. It does this by transferring heat
from engine metal to coolant, moving this heated
coolant to the radiator, and then transferring this
heat to the ambient air.
Coolant flow circuits for 2.4L and 3.3/3.8L engines
are shown in (Fig. 1), and 3.0L engine coolant rout-
ing is shown in (Fig. 2)
Fig. 1 Cooling System Operation 2.4L and 3.3/3.8L Engines
Fig. 2 Cooling System Operation 3.0L Engine
7 - 2 COOLING SYSTEMNS
GENERAL INFORMATION (Continued)

COOLANT RECOVERY SYSTEM (CRS)
This system works with the radiator pressure cap
to use thermal expansion and contraction of the cool-
ant to keep the coolant free of trapped air. Provides a
convenient and safe method for checking coolant
level and adjusting level at atmospheric pressure
without removing the radiator pressure cap. It also
provides some reserve coolant to cover deaeration
and evaporation or boiling losses. All vehicles are
equipped with this system and take various shapes
and forms. (Fig. 3) shows a typical system in the typ-
ical location.
See Coolant Level Service, and Deaeration, and
Pressure Cap sections for operation and service.
AUTOMATIC TRANSMISSION OIL COOLERÐ2.4L
Oil cooler is internal oil to coolant type, mounted
in the radiator left tank (Fig. 4). Rubber oil lines feed
the oil cooler and the automatic transmission. Use
only approved transmission oil cooler hose. Since
these are molded to fit space available, molded hoses
are recommended.
ENGINE THERMOSTAT
The engine cooling thermostats are a wax pellet
driven, reverse poppet choke type. They are designed
to provide the fastest warm up possible by prevent-
ing leakage through them and to guarantee a mini-
mum engine operating temperature of 88 to 93ÉC
(192 to 199ÉF). They also automatically reach wide
open so they do 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 fan, the
radiator, and the ambient temperature, not the ther-
mostat.
WATER PUMPS
A quick test to tell whether the pump is working is
to see if the heater warms properly. A defective pump
can not circulate heated coolant through the long
heater hose.The water pump on all models can
be replaced without discharging the air condi-
tioning system.
COOLANT
The cooling system is designed around the coolant.
The coolant must accept heat from engine metal, in
the cylinder head area near the exhaust valves. Cool-
ant then carries this heat to the radiator, where the
tube/fin assemblies of these components can give it
up to the air.
The use of aluminum cylinder heads, intake mani-
folds, and water pumps requires special corrosion
protection. MopartAntifreeze or the equivalent is
recommended for best engine cooling without corro-
sion, when mixed only to a freeze point of -37ÉC
(-35ÉF) to -59ÉC (-50ÉF). If it loses color or becomes
contaminated, drain, flush, and replace with fresh
properly mixed solution.
CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.
RADIATOR
The radiators are cross-flow types (horizontal
tubes) with design features that provide greater
strength along with sufficient heat transfer capabili-
Fig. 3 Coolant Recovery System
Fig. 4 Automatic Transmission Oil Cooler
NSCOOLING SYSTEM 7 - 3
GENERAL INFORMATION (Continued)

ties to keep the engine satisfactorily cooled (Fig. 5),
(Fig. 6), (Fig. 7) and (Fig. 8).
CAUTION: Plastic tanks, while stronger then brass
are subject to damage by impact, such as wrenches
etc., or by excessive torque on hose clamps.
If the plastic tank is damaged, replace the radia-
tor.
RADIATOR PRESSURE CAP
The radiator is equipped with a pressure cap that
releases excessive cooling system pressure; maintain-
ing a range of 97-124 kPa (14-18 psi).
The cooling system will operate at higher than
atmospheric pressure. The higher pressure raises thecoolant 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 coolant to return to radiator
from coolant reserve system tank by vacuum through
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. 9) and inspect coolant 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.
Fig. 5 Cooling ModuleÐ2.4L
Fig. 6 Cooling ModuleÐTrailer Tow (With Rear A/C)
7 - 4 COOLING SYSTEMNS
GENERAL INFORMATION (Continued)

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.
ENGINE BLOCK HEATER
The engine block heater is available as an optional
accessory on all models. The heater is operated by
ordinary house current (110 Volt A.C.) through a
power cord located behind the radiator grille. This
provides easier engine starting and faster warm-up
when vehicle is operated in areas having extremely
low temperatures. The heater is mounted in a core
hole (in place of a core hole plug) in the engine block,
with the heating element immersed in coolant.
Fig. 7 Cooling ModuleÐ3.0L (Front A/C Only)
Fig. 8 Cooling ModuleÐ3.0/3.3/3.8L (With Rear A/C)
Fig. 9 Radiator Pressure Cap Filler Neck
NSCOOLING SYSTEM 7 - 5
GENERAL INFORMATION (Continued)

DESCRIPTION AND OPERATION
WATER PIPESÐ3.0L ENGINE
The 3.0L engine uses metal piping beyond the
lower radiator hose to route (suction) coolant to the
water pump, which is located in the V of the cylinder
banks (Fig. 10).
These pipes are provided with inlet nipples for
thermostat bypass and heater return coolant hoses,
and brackets for rigid engine attachment. The pipes
employ O-rings for sealing at their interconnection
and to the water pump (Fig. 10).
COOLANT PERFORMANCE
Performance is measurable. For heat transfer pure
water excels (Formula = 1 btu per minute for each
degree of temperature rise for each pound of water).
This formula is altered when necessary additives to
control boiling, freezing, and corrosion are added as
follows:
²Pure Water (1 btu) boils at 100ÉC (212ÉF) and
freezes at 0ÉC (32ÉF)
²100 percent Glycol (.7 btu) can cause a hot
engine and detonation and will lower the freeze point
to -22ÉC (-8ÉF).
²50/50 Glycol and Water (.82 btu) is the recom-
mended combination that provides a freeze point of
-37ÉC (-35ÉF). The radiator, water pump, engine
water jacket, radiator pressure cap, thermostat, tem-
perature gauge, sending unit and heater are all
designed for 50/50 glycol.CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.
Where required, a 56 percent glycol and 44 percent
water mixture will provide a freeze point of -59ÉC
(-50ÉF).
CAUTION: Richer mixtures cannot be measured
with field equipment. This can lead to problems
associated with 100 percent glycol.
RADIATOR HOSES AND CLAMPS
WARNING: IF VEHICLE HAS BEEN RUN
RECENTLY, WAIT 15 MINUTES BEFORE WORKING
ON VEHICLE. RELIEVE PRESSURE BY PLACING A
SHOP TOWEL OVER THE CAP AND WITHOUT
PUSHING DOWN ROTATE IT COUNTERCLOCKWISE
TO THE FIRST STOP. ALLOW FLUIDS AND STEAM
TO ESCAPE THROUGH THE OVERFLOW TUBE.
THIS WILL RELIEVE SYSTEM PRESSURE
The hoses are removed by using constant tension
clamp pliers to compress the hose clamp.
A hardened, cracked, swollen or restricted hose
should be replaced. Do not damage radiator inlet and
outlet when loosening hoses.
Radiator hoses should be routed without any kinks
and indexed as designed. The use of molded hoses is
recommended.
Spring type hose clamps are used in all applica-
tions. If replacement is necessary replace with the
original MOPARtequipment spring type clamp.
WATER PUMPÐ2.4L ENGINE
The water pump has a diecast aluminum body and
housing with a stamped steel impeller. The water
pump bolts directly to the block. Cylinder block to
water pump sealing is provided by a rubber O-ring.
The water pump is driven by the timing belt. Refer
to Timing Belt in Group 9, Engine for component
removal providing access to water pump.
WATER PUMPÐ3.0L ENGINE
The pump bolts directly to the engine block, using
a gasket for pump to block sealing (Fig. 11). The
pump is serviced as a unit.
The water pump is driven by the timing belt. See
Timing Belt in Group 9, Engine for component
removal providing access to water pump.
Fig. 10 Engine Inlet Coolant Pipes 3.0L Engine
7 - 6 COOLING SYSTEMNS

RADIATOR COOLANT FLOW TEST
To determine whether coolant is flowing through
the cooling system, use the following procedure:
(1) If engine is cold, idle engine until normal oper-
ating temperature is reached. Then feel the upper
radiator hose. If it is hot, coolant is circulating.
WARNING: DO NOT REMOVE RADIATOR PRES-
SURE CAP WITH THE SYSTEM HOT AND UNDER
PRESSURE BECAUSE SERIOUS BURNS FROM
COOLANT CAN OCCUR.
(2) Remove radiator pressure cap when engine is
cold, idle engine until thermostat opens, you should
observe coolant flow while looking down the filler
neck. Once flow is detected install radiator pressure
cap.
RADIATOR FAN CONTROL
Fan control is accomplished two ways. A pressure
transducer on the compressor discharge line sends a
signal to the Powertrain Control Module (PCM)
which will activate the fan. In addition to this con-
trol, the fan is turned on by the temperature of the
coolant which is sensed by the coolant temperature
sensor which sends the message to the PCM. The fan
will not run during cranking until the engine starts
no matter what the coolant temperature is.
CAUTION: The solid state fan relay is attached to
the left frame rail near the lower radiator support.
The relay bracket, and fastener are used to dissi-
pate heat from the relay. Ensure the relay is prop-
erly attached to prevent the following:
²Intermittent engine overheating.
²Relay ªthermalº shutdown, or relay damage.
ELECTRIC FAN MOTOR TEST
Refer to Powertrain Diagnostic Manual for proce-
dure.
TESTING COOLING SYSTEM FOR LEAKS
With engine not running, wipe the radiator filler
neck sealing seat clean. The radiator should be full.
Attach the Radiator Pressure Tool to the radiator,
as shown in (Fig. 12) and apply 104 kPa (15 psi)
pressure. If the pressure drops more than 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 the engine up to normal operating
temperature to open the thermostat and allow the
coolant to expand. Reattach the tester. If the needleon the dial fluctuates it indicates a combustion leak,
usually a head gasket leak.
RADIATOR FAN OPERATION
Radiator Fan Control A/C Pressure
Fan
Operation
Low
Fan
Speed
30%High
Fan
Speed
100%Low
Fan
Speed
30%High
Fan
Speed
100%
On: 104ÉC
(220ÉF)110ÉC
(230ÉF)
Fan
Speed
Duty-
Cycles
(Ramps-
up) from
31% to
99%1,724
Kpa
(250
psi)2,068
Kpa
(300
psi)Fan
Speed
Duty-
Cycles
(Ramps-
up) from
31% to
99%
Off: 101ÉC
(214ÉF)Fan
Speed
Duty-
Cycles
(Ramps-
down)
from
99% to
31%1,710
Kpa
(248
psi)Fan
Speed
Duty-
Cycles
(Ramps-
down)
from
99% to
31%
Fig. 12 Pressure Testing Cooling System
7 - 14 COOLING SYSTEMNS
DIAGNOSIS AND TESTING (Continued)

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, race
the engine a few times. If an abnormal amount of
coolant or steam emits from the tail pipe, 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.
RADIATOR CAP TO FILLER NECK SEAL PRESSURE
RELIEF CHECK
The pressure cap upper gasket (seal) pressure
relief can be checked by removing the overflow hose
at the radiator filler neck nipple (Fig. 13). 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. By add-
ing or subtracting coolant through CRS bottle.
(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 WITHOUT PUSHING DOWN ROTATE COUN-
TERCLOCKWISE TO THE FIRST STOP. ALLOW FLU-
IDS TO ESCAPE THROUGH THE OVERFLOW TUBE
AND WHEN THE SYSTEM STOPS PUSHING COOL-
ANT AND STEAM INTO THE CRS TANK AND PRES-
SURE DROPS PUSH DOWN AND REMOVE THE CAP
COMPLETELY. SQUEEZING THE RADIATOR INLET
HOSE WITH A SHOP TOWEL (TO CHECK PRES-
SURE) BEFORE AND AFTER TURNING TO THE
FIRST STOP IS RECOMMENDED.
PRESSURE TESTING RADIATOR CAP
Dip the pressure cap in water, clean any deposits
off the vent valve or its seat and apply cap to end of
Radiator Pressure Tool. 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 cap. SeeCAUTION.
If the pressure cap tests properly while positioned
on Radiator Pressure Tool (Fig. 14), but will not hold
pressure or vacuum when positioned on the radiator.
Inspect the radiator filler neck and cap top gasket for
irregularities that may prevent the cap from sealing
properly.
CAUTION: Radiator Pressure Tool is very sensitive
to small air leaks that will not cause cooling system
problems. A pressure cap that does not have a his-
tory 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.
LOW COOLANT LEVEL AERATION
Low coolant level in a cross flow radiator will
equalize in both tanks with engine off. With engine
Fig. 13 Radiator Pressure Cap Filler Neck
Fig. 14 Pressure Testing Radiator Cap
NSCOOLING SYSTEM 7 - 15
DIAGNOSIS AND TESTING (Continued)

at running operating temperature the high pressure
inlet tank runs full and the low pressure outlet tank
drops:
²Transmission oil will become hotter.
²High reading shown on the temperature gauge.
²Air in the coolant can cause loss of flow through
the heater.
²Exhaust gas leaks into the coolant also can
cause the same problems.
DEAERATION
Air can only be removed from the system by gath-
ering under the pressure cap. On the next heat up it
will be pushed past the pressure cap into the CRS
tank by thermal expansion of the coolant. It then
escapes to the atmosphere in the CRS tank and is
replaced with solid coolant on cool down.
TEMPERATURE GAUGE INDICATION
At idle with Air Conditioning off the temperature
gauge will rise slowly to about 5/8 gauge travel, the
fan will come on and the gauge will quickly drop to
about 1/2 gauge travel. This is normal.
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE
Do not remove radiator cap for routine cool-
ant level inspections.
The coolant reserve system provides a quick visual
method for determining the coolant level without
removing the radiator cap.With the engine cold
and not running,simply observe the level of the
coolant in the reserve tank (Fig. 3). The coolant level
should be between the minimum and maximum
marks.
COOLANTÐADDING ADDITIONAL
The radiator cap should not be removed.
When additional coolant is needed to maintain this
level, it should be added to the coolant reserve tank.
Use only 50/50 mix of ethylene glycol type antifreeze
and water.
CAUTION: Do not use well water, or suspect water
supply in cooling system. A 50/50 ethylene glycol
and distilled water mix is recommended.
COOLANT LEVEL SERVICE
The cooling system is closed and designed to main-
tain coolant level to the top of the radiator.
When servicing requires a coolant level check in
the radiator, the engine must beoffandnotunder
pressure. Drain several ounces of coolant from the
radiator draincock while observing the CoolantRecovery System (CRS) Tank. Coolant level in the
CRS tank should drop slightly. Then remove the radi-
ator cap. The radiator should be full to the top. If
not, and the coolant level in the CRS tank is at the
MIN mark there is an air leak in the CRS system.
Check hose or hose connections to the CRS tank,
radiator filler neck or the pressure cap seal to the
radiator filler neck for leaks.
COOLING SYSTEMÐDRAINING
Without removing radiator pressure cap and
with system not under pressure,shut engine off
and open draincock. The coolant reserve tank should
empty first, then remove radiator pressure cap. (if
not, see Testing Cooling System for leaks). To vent
2.4L engine remove the coolant temperature sensor
located above water outlet housing (Fig. 15). The 3.0/
3.3/3.8L engines have an air bleed vent on the ther-
mostat.
Removal of a sensor is required because the ther-
mostat does not have an air vent. Sensor removal
allows an air bleed for coolant to drain from the
engine block.
COOLING SYSTEMÐREFILLING
First clean system to remove old coolant, see Cool-
ing System Cleaning.
Fill the system, using the correct antifreeze as
described in the Coolant Section. Fill the system to
50 percent of its capacity with 100 percent glycol.
Then complete filling system with water. The 2.4L
engine requires venting by removal of the coolant
sensor on top of the water outlet connector (Fig. 15).
When coolant reaches this hole:
²Install coolant sensor and tighten to 7 N´m (60
in. lbs.) for 2.4L Engines.
Fig. 15 Coolant Temperature SensorÐ2.4L Engine
Drain/Fill
7 - 16 COOLING SYSTEMNS
DIAGNOSIS AND TESTING (Continued)

NOTE: It is normal for the water pump to weep a
small amount of coolant from the weep hole (black
stain on water pump body). Do not replace the
water pump if this condition exists. Replace the
water pump if a heavy deposit or a steady flow of
green/brown engine coolant is evident on water
pump body from the weep hole (shaft seal failure).
Be sure to perform a thorough analysis before
replacing water pump.
ACCESSORY DRIVE BELT
When inspecting serpentine drive belts, small
cracks that run across the ribbed surface of the belt
from rib to rib (Fig. 37), are considered normal. these
are not reasons to replace the belt. However, cracks
running along the rib (not across) are not normal.
Any belt with cracks running along the rib must be
replaced (Fig. 37). Also replace the belt if it has
excessive wear, frayed cords or severe glazing.
RADIATOR PRESSURE CAP
INSPECTION
Hold the cap in hand,right side up. The vent
valve at the bottom of the cap should open. If the
rubber gasket has swollen and prevents the valve
from opening, replace the cap.
Hold the cleaned cap in handupside down.If any
light shows between vent valve and rubber gasket,
replace cap.Do not use a replacement cap that
has a spring to hold the vent shut.
Replacement cap must be of the type designed for
coolant reserve system with a completely sealed dia-
phragm spring, and rubber gasket to seal to fillerneck top surface. This design assures coolant return
to radiator.
COOLING SYSTEM CLEANING
Drain cooling system (see:Cooling System
Draining) and refill with clean water (see:Cooling
System Refilling). Run engine with radiator cap
installed until upper radiator hose is hot. Stop
engine and drain water from system. If water is
dirty; fill, run, and drain system again, until water
runs clear.
REVERSE FLUSHING THE RADIATOR
Drain cooling system and remove radiator hoses
from engine. Install suitable flushing gun in radiator
lower hose. Fill radiator with clean water and turn
on air in short blasts.
CAUTION: Internal radiator pressure must not
exceed 138 kPa (20 psi) as damage to radiator may
result. Continue this procedure until water runs
clear.
REVERSE FLUSHING THE ENGINE
Drain radiator (see:Draining Cooling System)
and remove hoses from radiator. Remove engine ther-
mostat and reinstall thermostat housing. Install suit-
able flushing gun to thermostat housing hose. Turn
on water, and when engine is filled, turn on air, but
no higher than 138 kPa (20 psi) in short blasts. Allow
engine to fill between blasts of air. Continue this pro-
cedure until water runs clean. Reinstall thermostat
using a new housing gasket. Fill cooling system (See
Refilling).
CHEMICAL CLEANING
One type of corrosion encountered with aluminum
cylinder heads is aluminum hydroxide deposits. Cor-
rosion products are carried to the radiator and depos-
ited when cooled off. They appear as dark grey when
wet and white when dry. This corrosion can be
removed with a two part cleaner (oxalic acid and
neutralizer) available in auto parts outlets. Follow
manufacturers directions for use.
ADJUSTMENTS
PROPER BELT TENSION
Satisfactory performance of the belt driven accesso-
ries depends on proper belt tension. Belt tensioning
should be performed with the aid of a Burroughs
gauge Special Tool C-4162. Because of space limita-
tions in the engine compartment, the use of the
gauge may be restricted. Raise the vehicle on a hoist
Fig. 37 Serpentine Drive Belt Wear Patterns
NSCOOLING SYSTEM 7 - 25
CLEANING AND INSPECTION (Continued)