radiator cap DODGE NEON 2000 Service User Guide

CAUTION: The radiator pressure tester is very sen-
sitive to small air leaks that will not cause cooling
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 the tool
upside down, and recheck the pressure cap to con-
firm that the cap is faulty.
If the pressure cap tests properly while posi-
tioned the on radiator pressure tester, but will not
hold pressure or vacuum when positioned on the
filler neck, inspect the filler neck and cap top gas-
ket for irregularities that may prevent the cap from
sealing properly.
LOW COOLANT LEVEL AERATION
²Will cause corrosion in the system.
²High reading shown on the temperature gauge.
²Air in the coolant will also cause loss of flow
through the heater.
²Exhaust gas leaks into the coolant can also
cause the above 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 coolant
recovery container by thermal expansion of the cool-
ant. It then escapes to the atmosphere in the coolant
recovery container and is replaced with coolant on
cool down.
TEMPERATURE GAUGE INDICATION
At idle the temperature gauge could rise slowly to
about 1/2 gauge travel. The fan will come on and the
gauge could drop to about 1/3 gauge travel, this is
normal.
ENGINE BLOCK HEATER
If heater unit does not operate (Fig. 15), possible
causes can be either the power cord or the heater ele-
ment. Test the power cord for continuity with a 110-
volt voltmeter or 110-volt test light. Test heater
element continuity with an ohmmeter or a 12-volt
test light.
CAUTION: To prevent damage, the power cord
must be secured in its retainer clips and away from
any components that may cause abrasion or dam-
age, such as linkages, exhaust components, etc.
SERVICE PROCEDURES
COOLANT LEVEL CHECKÐROUTINE
NOTE: Do not remove radiator cap for routine cool-
ant level inspections.
The coolant recovery/reserve system provides a
quick visual method for determining the coolant level
without removing the radiator cap. Simply observe,
with the engine idling and warmed up to normal
operating temperature, that the level of the coolant
in the recovery/reserve container (Fig. 16) is between
the FULL HOT and ADD marks.
Fig. 14 Pressure Testing Radiator Cap
1 ± PRESSURE CAP
2 ± PRESSURE TESTER
Fig. 15 Engine Block Heater
1 ± CORE PLUG
2 ± BLOCK HEATER
3 ± POWER CORD
PLCOOLING SYSTEM 7 - 17
DIAGNOSIS AND TESTING (Continued)

COOLANTÐADDING ADDITIONAL
NOTE: The radiator cap should not be removed.
When additional coolant is needed, it should be
added to the coolant recovery/reserve container (Fig.17). Use only 50/50 concentration of ethylene glycol
type antifreeze and water
COOLANT LEVELÐSERVICING
NOTE: The cooling system is closed and designed
to maintain 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 drain cock while observing the Coolant
Recovery Container. Coolant level in the container
should drop slightly. Then remove the radiator cap,
(Fig. 17). The radiator should be full to the top. If
not, and the coolant level in the recovery container is
at the ADD mark there is a air leak in the recovery
system. Check hose or hose connections to the recov-
ery container, radiator filler neck or the pressure cap
seal to the radiator filler neck for leaks.
Fig. 17 Coolant Recovery Container and Pressure Cap Locations
1 ± ENGINE OIL FILL
2 ± ENGINE COOLANT RECOVERY CONTAINER3 ± ENGINE OIL DIPSTICK
4 ± COOLING SYSTEM PRESSURE CAP
Fig. 16 Coolant Level
1 ± COOLANT RECOVERY CONTAINER
7 - 18 COOLING SYSTEMPL
SERVICE PROCEDURES (Continued)

COOLING SYSTEMÐDRAINING
NOTE: Drain, flush, and fill the cooling system at
the mileage or time intervals specified in Group 0,
Lubrication and Maintenance. If the solution is dirty,
rusty, or contains a considerable amount of sedi-
ment; clean and flush with a reliable cooling system
cleaner. Care should be taken in disposing of the
used engine coolant from your vehicle. Check gov-
ernmental regulations for disposal of used engine
coolant.
Without removing radiator pressure cap and
with system not under pressure:
(1) Shut engine off and turn draincock counter-
clockwise to open (Fig. 18).
(2) The coolant reserve tank should empty first,
then remove the pressure cap. (if not, Refer to Test-
ing Cooling System for leaks).
COOLING SYSTEMÐREFILLING
First clean system to remove old glycol, see Cooling
System Cleaning.
Fill system with 50/50 glycol/water mix. Use anti-
freeze described in Coolant section.
Continue filling system until full, this provides bet-
ter heater performance.Be careful not to spill
coolant on drive belts or the generator.
Fill coolant reserve/recovery system to at least the
FULL HOT mark with 50/50 solution. It may be nec-
essary to add coolant to the reserve/recovery con-
tainer after three or four warm-up/cool down cycles
to maintain coolant level between the FULL HOT
and ADD marks; if any trapped air was removed
from the system.
REMOVAL AND INSTALLATION
WATER PUMP
REMOVAL
(1) Raise vehicle on a hoist. Remove right inner
splash shield.
(2) Remove accessory drive belts. Refer to proce-
dure in this section.
(3) Drain cooling system. Refer to Cooling System
Draining in this section.
(4) Remove power steering pump attaching bolts
and set pump and assembly aside. Power steering
lines do not need to be disconnected.
(5) Remove upper and lower torque isolator struts.
(6) Support engine from the bottom and remove
right engine mount attaching bolt.
(7) Remove right engine mount bracket.
(8) Remove timing belt and timing belt tensioner.
Refer to Group 9, Engine for procedures.
(9) Remove camshaft sprocket and rear timing belt
cover. Refer to Group 9, Engine for procedures.
(10) Remove water pump attaching screws to
engine and remove pump (Fig. 19).
INSTALLATION
(1) Apply MopartDielectric Grease to O-ring
before installation.
(2) Install new O-ring gasket in water pump body
O-ring groove (Fig. 20).
CAUTION: Make sure O-ring gasket is properly
seated in water pump groove before tightening
screws. An improperly located O-ring may cause
damage to the O-ring, resulting in a coolant leak.
(3) Assemble pump body to block and tighten
screws to 12 N´m (105 in. lbs.). Pressurize cooling
system to 15 psi with pressure tester and check
water pump shaft seal and O-ring for leaks.
Fig. 18 Cooling System Drain Cock Location
1 ± DRAIN COCKFig. 19 Water Pump
1 ± CYLINDER BLOCK
2 ± PUMP BODY
PLCOOLING SYSTEM 7 - 19
SERVICE PROCEDURES (Continued)

(3) Remove thermostat/engine outlet connector
bolts (Fig. 22).
(4) Remove thermostat and O-ring assembly.
INSTALLATION
(1) Clean all sealing surfaces.
(2) Place the new thermostat assembly into the
thermostat housing/outlet connector. Align vent with
notch in cylinder head.
(3) Install thermostat housing/outlet connector
onto cylinder head and tighten bolts to 12.5 N´m (110
in. lbs.).
(4) Install upper radiator hose.
(5) Connect the coolant recovery/reserve system
hose.
(6) Refill cooling system. Refer to procedure in this
section.
RADIATOR
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.
(1) Disconnect negative cable from battery.
(2) Drain cooling system. Refer to procedure in
this section.
(3) Remove upper radiator hose from the radiator.
(4) Disconnect and cap automatic transmission
hoses, if equipped.(5) Disconnect cooling fan motor electrical connec-
tor.
(6) Remove cooling fan module retaining screws,
located on the top of the shroud (Fig. 23). Lift shroud
up and out of bottom shroud attachment clips sepa-
rating shroud from radiator.
(7) Remove the lower radiator hose.
(8) Remove upper radiator isolator bracket mount-
ing screws (Fig. 24). Disconnect the engine block
heater wire, if equipped.
(9) Remove the air conditioning condenser attach-
ing screws located at the front of the radiator, if
equipped (Fig. 25), then lean condenser forward.
NOTE: It is not necessary to discharge the air con-
ditioning system to remove the radiator.
Fig. 22 Thermostat/Engine Outlet Connector
1 ± PRESSURE CAP
2 ± THERMOSTAT HOUSING/ENGINE OUTLET CONNECTOR
3 ± THERMOSTAT
4 ± O-RING
5 ± VENT FACING UP
Fig. 23 Fan Module Mounting
1 ± SCREWS
2 ± LOWER MOUNTS
3 ± FAN MOTOR ELECTRICAL CONNECTOR
Fig. 24 Radiator Mounting
1 ± UPPER RADIATOR HOSE
2 ± UPPER RADIATOR MOUNTS
PLCOOLING SYSTEM 7 - 21
REMOVAL AND INSTALLATION (Continued)

INSTALLATION
(1) Install the fan module into the clips on the
lower radiator tank.
(2) Install the fan module retaining screws and
tighten to 7.5 N´m (65 in. lbs.).
(3) Connect fan module electrical connector.For
wiring diagrams of fan motor systems, refer to
Group 8W, Wiring Diagrams.
(4) Install the upper radiator hose to radiator (Fig.
27). Align hose and position clamp so it will not
interfere with the engine or the hood.
(5) Connect negative cable to battery.
(6) Fill cooling system. Refer to procedure in this
section.
COOLANT RECOVERY CONTAINER
REMOVAL
(1) Disconnect recovery hose from water outlet
connector/thermostat housing (Fig. 29).
(2) Remove container attaching fasteners (Fig. 30).
(3) Remove coolant recovery container.
INSTALLATION
(1) Install coolant recovery container and tighten
fasteners to 4 N´m (35 in. lbs.) (Fig. 30).
Fig. 27 Upper Radiator Hose
1 ± UPPER RADIATOR HOSE
2 ± UPPER RADIATOR MOUNTS
Fig. 28 Fan ModuleÐRemoval/Installation
1 ± SCREWS
2 ± LOWER MOUNTS
3 ± FAN MOTOR ELECTRICAL CONNECTOR
Fig. 29 Recovery Container Hose
1 ± RECOVERY HOSE
2 ± ENGINE COOLANT RECOVERY CONTAINER
3 ± PRESSURE CAP
Fig. 30 Coolant Recovery Container
1 ± COOLANT RECOVERY CONTAINER
2 ± SCREW
3 ± NUT
PLCOOLING SYSTEM 7 - 23
REMOVAL AND INSTALLATION (Continued)

SHROUD
REMOVAL
(1) Remove cooling fan module. Refer to procedure
in this section.
(2) Remove fan and fan motor as previously
described.
INSTALLATION
(1) Install fan motor and fan as previously
described.
(2) Install cooling fan module. Refer to procedure
in this section.
CLEANING AND INSPECTION
WATER PUMP
Replace water pump body assembly if it has any of
these defects:
(1) Cracks or damage on the body.
(2) Coolant leaks from the shaft seal, evident by
coolant traces on the pump body.
(3) Loose or rough turning bearing.
(4) Impeller rubs either the pump body or the
engine block.
(5) Impeller loose or damaged.
(6) Sprocket or sprocket flange loose or damaged.
ACCESSORY DRIVE BELT INSPECTION
Belt replacement under any or all of the following
conditions is required, excessive wear, frayed cords or
severe glazing.
Poly-V Belt system may develop minor cracks
across the ribbed side. These minor cracks are con-
sidered normal and acceptable. Cracks parallel are
not (Fig. 40).
NOTE: Do not use any type of belt dressing or
restorer on Poly-V Belts.
COOLING SYSTEM CAP
Hold the cap in your hand,right side up(Fig. 41).
The vent valve at the bottom of the cap should open
with a slight pull. If the rubber gasket has swollen,
preventing the valve from opening, replace the cap.
If any light can be seen between vent valve and
the rubber gasket, replace the cap.Use only a
replacement cap that has a spring to hold the
vent shut.
A replacement cap must be of the type designed for
coolant reserve systems. This design ensures system
pressurization.
COOLING SYSTEM CLEANING
(1) Drain cooling system. Refer to Cooling System
Draining in this section for procedure.
(2) Refill with clean water. Refer to Cooling Sys-
tem Refilling in this section for procedure.
(3) Run engine with radiator cap installed until
upper radiator hose is hot.
(4) Stop engine and drain water from system. If
water is dirty, fill, run and drain the system again
until water runs clear.
RADIATOR FLUSHING
(1) Drain cooling system. Refer to Cooling System
Draining in this section for procedure.
(2) Remove radiator hoses from engine.
(3) Install suitable flushing gun in radiator lower
hose.
(4) 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.
ENGINE FLUSHING
(1) Drain radiator. Refer to Cooling System Drain-
ing in this section for procedure.
(2) Remove hoses from radiator.
Fig. 40 Drive Belt Wear Pattern
1 ± NORMAL CRACKS BELT OK
2 ± NOT NORMAL CRACKS REPLACE BELT
7 - 28 COOLING SYSTEMPL
DISASSEMBLY AND ASSEMBLY (Continued)

(3) Remove engine thermostat and reinstall ther-
mostat housing. A gasket may be needed to seal thehousing to cylinder head because the seal is part of
thermostat.
(4) Install suitable 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 procedure until water
runs clean.
(5) Install thermostat and fill cooling system.
Refer to Cooling System Refilling in this section for
procedure.
REVERSE FLUSHING
Reverse flushing of the cooling system is the forc-
ing of water through the cooling system, using air
pressure in a direction opposite to that of the normal
flow of water. This is only necessary with dirty sys-
tems and evidence of partial plugging.
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
BELT TENSION
For belt tension adjustment procedure, refer to
Accessory Drive Belt Removal and Installation proce-
dure.
Fig. 41 Cooling System Pressure Cap
1 ± PRESSURE RATING
2 ± FILLER NECK SEAL
3 ± PRESSURE VALVE
4 ± VACUUM VENT VALVE (SHOWN IN SEALING POSITION)
PLCOOLING SYSTEM 7 - 29
CLEANING AND INSPECTION (Continued)

SPECIFICATIONS
COOLING SYSTEM CAPACITY
TORQUE SPECIFICATIONSSPECIAL TOOLS
COOLING
6.2 Liters (6.5 qts.)
CAPACITY, Includes Heater and Coolant Reserve
System
DESCRIPTION N´m Ft.
Lbs.In.
Lbs.
A/C Condenser to RadiatorÐ
Screws5.4 Ð 50
Automatic Belt Tensioner
PulleyÐBolt27 20 Ð
Coolant Recovery ContainerÐ
Nut/Screw4Ð35
Fan Module to RadiatorÐ
Screws7.2 Ð 65
Fan Motor to ShroudÐScrews 3.8 Ð 34
Fan Blade to Motor ShaftÐ
Nut3.8 Ð 34
In Rush Current SupressorÐ
Screw2.6 Ð 23
Generator MountingÐPivot
Bolt54 40 Ð
Generator MountingÐLocking
Nut54 40 Ð
Radiator (Cooling Module) to
BodyÐScrews10 Ð 90
Thermostat Housing/Water
Outlet ConnectorÐScrews12 Ð 105
Transmission HoseÐClamps 2 Ð 18
Water Pump to Engine
BlockÐBolts12 Ð 105
Water Pump Inlet Tube to
Engine BlockÐBolts12 Ð 105
Hose Clamp Pliers 6094
Coolant Refractometer 8286
7 - 30 COOLING SYSTEMPL

should not be disassembled to determine the
cause of low compression unless some malfunc-
tion is present.
(11) Clean or replace spark plugs as necessary and
adjust gap as specified in Group 8, Electrical.
Tighten to specifications.
(12) Test resistance of spark plug cables. Refer to
Group 8, Electrical Ignition System Secondary Cir-
cuit Inspection.
(13) Test coil output voltage, primary and second-
ary resistance. Replace parts as necessary. Refer to
Group 8, Electrical Ignition System.
(14) Check fuel pump pressure at idle and differ-
ent RPM ranges. Refer to Group 14, Fuel System for
Specifications.
(15) The air filter elements should be replaced as
specified in Group 0, Lubrication and Maintenance.
(16) Inspect crankcase ventilation system as out
lined in Group 0, Lubrication and Maintenance. For
emission controls see Group 25, Emission Controls
for service procedures.
(17) Inspect and adjust accessory belt drives refer-
ring to Group 7, Cooling System, Accessory Drive
Belts for proper adjustments.
(18) Road test vehicle as a final test.
CYLINDER COMBUSTION PRESSURE LEAKAGE
TEST
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE
BECAUSE SERIOUS BURNS FROM COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn the engine
OFF.
Clean spark plug recesses with compressed air.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379kPa (200 psi) maximum, with 552 kPa (80 psi) rec-
ommended.
Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage per cylinder.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
LASH ADJUSTER (TAPPET) NOISE DIAGNOSIS
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) During this time, turn engine off and let set for
a few minutes before restarting. Repeat this several
times after engine has reached normal operating
temperature.
(4) Low oil pressure.
(5) The oil restrictor pressed into the vertical oil
passage to the cylinder head is plugged with debris.
(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head. Depress part of rocker
arm over adjuster. Normal adjusters should feel very
firm. Spongy adjusters can be bottomed out easily.
b. Remove suspected rocker arms (sohc) or lash
adjuster (dohc) and replace.
ENGINE OIL LEAK INSPECTION
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
PLENGINE 9 - 9
DIAGNOSIS AND TESTING (Continued)

CRANKSHAFT
A nodular cast iron crankshaft is used. The engine
has five main bearings. The number three main is
flanged to control thrust. The mains and connecting
rod journals have undercut fillet radiuses that are
deep rolled for added strength. To optimize bearing
loading, eight counterweights are used. Hydrody-
namic seals provide end sealing, where the crank-
shaft exits the block. Anaerobic gasket material is
used for parting line sealing. A sintered iron timing
belt sprocket is mounted on the crankshaft nose. This
sprocket transmits crankshaft movement, via timing
belt to the camshaft sprocket providing timed valve
actuation.
PISTONS
The engineDOES NOThave provision for a free
wheeling valve train. Non free wheeling valve train
means, in the event of a broken timing belt pistons
will contact the valves. The engine uses pressed-in
piston pins to attach forged powdered metal connect-
ing rods. The connecting rods are a cracked cap
design and are not repairable. Hex head cap screw
are used to provide alignment and durability in the
assembly. Pistons and connecting rods are serviced as
an assembly.
PISTON RINGS
The piston rings include a molybdenum faced top
ring for reliable compression sealing and a taper
faced intermediate ring for additional cylinder pres-
sure control. Oil Control Ring Package consist of two
steel rails and an expander spacer.
CYLINDER HEAD
The aluminum cylinder head features a Single
Over Head Camshaft (SOHC), four-valves per cylin-
der, cross flow design. The valves are arranged in
two inline banks, with the two intake per cylinder
facing toward the radiator. The exhaust valves facing
toward the dash panel. Rocker arm shafts mount
directly to the cylinder head. It incorporates powder
metal valve guides and seats. The hollow rocker arm
shafts supplies oil to the hydraulic lash adjusters,
camshaft and valve mechanisms.
CAMSHAFT
The nodular iron camshaft has five bearing jour-
nals and three cam lobes per cylinder. Provision for a
cam position sensor is provided on the camshaft at
the rear of cylinder head which also acts as thrust
plate. A hydrodynamic oil seal is used for oil control
at the front of the camshaft.
VALVES
Four valves per cylinder are actuated by roller
rocker arms/hydraulic lash adjusters assemblies
which pivot on rocker arm shafts. All valves have
chrome plated valve stems. Viton rubber valve stem
seals are integral with spring seats. Valve springs,
spring retainers, and locks are conventional design.
INTAKE MANIFOLD
The intake manifold is a molded plastic composi-
tion, attached to the cylinder head with five fasten-
ers. This long branch design enhances low and mid-
range torque.
EXHAUST MANIFOLD
The exhaust manifold is made of nodular cast iron
for strength and high temperatures. Exhaust gasses
exit the manifold into an articulated joint connection
and exhaust pipe.
COMPONENT REPLACEMENT
If any of the following parts have been changed or
replaced:
²Camshaft
²Camshaft Position Sensor
²Camshaft Position Sensor Target Magnet
²Cylinder Block
²Cylinder Head
²Water Pump
²Powertrain Control Module (PCM)
²Timing Belt and Timing Belt Tensioner
The camshaft and crankshaft timing relearn proce-
dure must be performed. Refer to the component
Removal and Installation procedure in this section.
9 - 16 2.0L SOHC ENGINEPL
DESCRIPTION AND OPERATION (Continued)