Nissan PULSAR N13 Series / ASTRA LD Series. Manual - part 17

Cooling and Heating Systems

the cylinder head or cylinder block and renew the
cylinder head gasket.

(2) Crack in the cylinder head or cylinder block:

Repair or renew as necessary.

NOTE; Check the engine for internal leak-
age by withdrawing the dipstick and inspect-
ing for emulsified oil. Run the engine and
check for excessive steam at the exhaust
pipe which would indicate coolant leakage
into the combustion chamber.

COOLANT LOSS BY OVERFLOW

(1) Overfull system: Drain the excess coolant

from the system.

(2) Faulty radiator cap: Renew the faulty cap.

(3)

Blocked radiator core tubes: Clean or renew

the radiator core.

(4) Faulty thermostat: Renew the thermostat.
(5) Coolant foaming due to poor quality anti-

freeze or corrosion inhibitor: Drain the system and
renew the coolant and additive.

Renew the radiator cap if the sealing rubber has

deteriorated.

ENGINE OVERHEATING

(1) Radiator cap defective: Renew the radiator

cap.

(2) Incorrect fuel mixture: Check the fuel system

as described in the Fuel and Engine Management
section.

(3) Obstructed air passage through the radiator

core from the front to the rear: Blow the obstruction
from the rear to the front of the radiator core using
compressed air or water pressure.

(4) Faulty thermostat: Renew the thermostat.
(5) Incorrect ignition timing: Check and adjust

the ignition timing as described in the Engine Tune-up
section.

(6) Incorrect valve timing: Set the valve timing

as described in the Engine section.

(7) Loss of coolant from the overflow: Check

and rectify as described under the heading Coolant
Loss By Overflow.

(8) Poor circulation: Check and rectify as de-

scribed under the heading Coolant Circulation Faulty.

(9) Low engine oil level: Stop the engine imme-

diately and replenish the oil in the sump.

(10) Restricted muffler, catalytic converter or

damaged tailpipe, accompanied by loss of power:
Remove the restrictions or renew the faulty com-
ponents as necessary.

(11) Incorrectly adjusted or dragging brakes:

Check and rectify by adjustment or renewal of
components.

(12) Faulty temperature gauge and/or sender unit:

Check and rectify as necessary.

NOTE: Engine overheating is indicated by
an excessive rise in engine temperature
shown by the temperature gauge.

Overheating is usually accompanied by

steam emitting from the coolant overflow
pipe and loss of engine power. A blown
cylinder head gasket may be indicated by
bubbles in the coolant.

COOLANT CIRCULATION FAULTY

(1) Partial blockage of the radiator core tubes:

reverse flush or renew the radiator core.

(2) Sludge deposits in the engine water jacket:

Clean and flush the engine water jacket and add
inhibitor to the coolant.

(3)  Faulty water pump: Renew the water pump.
(4)  Faulty thermostat: Renew the thermostat.
(5)  Collapsing lower radiator hose: Renew the

lower radiator hose and check the radiator core tubes.

(6) Insufficient coolant in the system: Replenish

the coolant and check for leaks.

NOTE: If rust or sludge deposits are sus-
pected, check the color of the coolant in the
radiator. Rusty or muddy coolant indicates
rust or sludge in the system.

2. HEATER AND AIR CONDITIONER

TROUBLE SHOOTING

NO HOT AIR INSIDE VEHICLE

Faulty thermostat: Renew the thermostat.
Faulty heater valve: Check and renew the

Blocked heater hoses: Remove the blockage.
Blocked heater core: Clean or renew the core.

NOTE: Ensure that the engine is reaching

normal operating temperature. If in doubt
check the operation of the thermostat as
described under the Thermostat heading in
this section.

(1)
(2)

valve.

(3)
(4)

Cooling and Heating Systems

Installed view of the heater hoses. 1.6 liter models

with the air cleaner removed for clarity

When the engine is at normal operating

temperature and the heater valve is open,
both of the heater hoses should feel
warm/hot. If the valve is not allowing the
coolant to flow, one hose will be hot while
the other will be cold.

NO COOLED AIR INSIDE VEHICLE

(1) Compressor drive belt slipping or broken:

Renew and/or adjust the drive belt as described in the
Engine Tune-up section.

(2) Insufficient refrigerant: Check the system for

leaks and charge as necessary. Refer to the Air
Conditioning heading in this section for information
on checking the refrigerant level.

(3) Compressor inoperative: Check for power to

the compressor clutch before removing the compres-
sor for repair by a specialist.

(4) Heater system allowing warm air to mix with

cooled air: Check the operation of the heater system.

NOTE: The above trouble shooting proce-
dures are basic checks only. If the air
conditioning system is suspect, it is rec-
ommended that the vehicle be taken to an
authorized dealer for testing and repair.
It is normal for water to be seen drain-
ing under the vehicle from the evaporator
after the vehicle has been operated with
the air conditioning on.

3. DESCRIPTION

The cooling system is of the sealed, pressurized

type with fan and water pump assistance. The system
is pressurized in order to raise the boiling point of the
coolant and so increase the efficiency of the engine.

Provision for pressure and vacuum relief of the
system is incorporated in the radiator cap.

The radiator overflow hose is connected to a

reserve tank mounted adjacent to the battery. As the
coolant volume expands due to an increase in tem-
perature, the pressure valve in the radiator cap opens
and allows the excess coolant to flow into the reserve
tank. When the engine is stopped and the temperature
of the coolant falls, the vacuum valve in the radiator
cap opens and allows the excess coolant in the reserve
tank to siphon back into the radiator. Thus the
necessity for frequent topping up of the coolant is
eliminated.

The temperature of the cooling system is con-

trolled by a thermostat located in the thermostat
housing attached to the cylinder head.

The thermostat prevents circulation of coolant

through the radiator by directing coolant through the
by-pass circuit, until the engine has reached operating
temperature. This restricted circulation allows the
engine to reach operating temperature quickly, im-
proving drivability and fuel economy.

Removal of the thermostat to cure overheating is

not recommended because the by-pass circuit will
remain open reducing the amount of water flowing
through the radiator.

An anti-corrosion inhibitor should always be

added to the coolant to protect the cooling and
heating systems from corrosion.

The water pump is mounted to the front of the

engine and is driven by the camshaft drive belt. It is
equipped with a double row ball bearing and a spring
loaded seal assembly. The water pump is a disposable
unit and cannot be repaired.

The fan is driven by an electric motor which is

actuated by the coolant temperature sensor and the
control unit.

On vehicles equipped with air conditioning, an

additional electric fan is mounted to the radiator. This
fan is controlled by a switch connected to the air
conditioning compressor.

The radiator consists of an aluminum core with

plastic side tanks. Minor damage to the core can be
repaired using Nissan repair agent.

The left hand tank of the radiator houses the

transaxle oil cooler on automatic transaxle models.

To drain the cooling system a drain plug is

provided on the lower radiator pipe outlet.

4. RADIATOR

NOTE: To avoid scalding, use caution when
releasing the radiator cap on an engine
which is at the normal operating tempera-
ture. Turn the cap anti-clockwise to the first
stop and allow any pressure in the system to
release. When the pressure is released turn
the cap past the stop and remove it from the
radiator.

Cooling and Heating Systems

TO DRAIN AND REFILL

(1) Place a drain tin under the radiator drain

plug.

(2) Switch the heater controls to the maximum

heat position.

(3) Remove the radiator cap and open the

radiator drain plug.

(4) Disconnect the reserve tank hose from the

radiator filler neck.

(5) Lower the end of the hose and drain the

coolant from the reserve tank.

(6) After all the coolant has drained from the

cooling system, install the radiator drain plug
ensuring
that the plug seal is in good condition.

(7) Disconnect the wire from the temperature

sender switch and remove the switch using a suitable
spanner.

(8) Using a clean container, mix Nissan long life

coolant with clean soft water to the proportions
stipulated on the coolant container.

(9) Slowly pour the premixed coolant into the

radiator until the radiator is full and all air has
escaped through the temperature sender switch hole.
Install the radiator cap.

(10) Fill the coolant reserve tank to the Maxi-

mum mark.

(11) Start the engine and allow it to idle.
(12) When coolant starts to flow through the

temperature sender switch hole, install the temperature
sender switch and tighten securely.

(13) Continue idling the engine until the cooling

fan is activated.

(14) Switch the engine off and allow it to cool.
(15) Refill the radiator using coolant and install

the radiator cap.

Dismantled view of the radiator and associated components. Automatic transaxle model with

air conditioning.

Cooling and Heating Systems

(16) After the vehicle has been driven several

kilometers check the coolant level in the reserve tank
and top up if necessary.

TO REMOVE

(1) Drain the cooling system as previously de-

scribed.

(2) Loosen the hose clamps and disconnect the

hoses from the radiator.

(3) If applicable disconnect the automatic trans-

axle oil cooler hoses from the left hand side radiator
tank. Plug the hoses and fittings to prevent the entry
of dirt and the loss of fluid.

(4) Disconnect the hose from the reserve tank at

the top of the radiator.

(5) On models with air conditioning, remove the

hoses and support bracket bolts and move the bracket
and hoses away from the top of the radiator.

(6) Remove the radiator support bracket bolts

from the radiator support panel and lift the radiator
from the lower mountings and out of the vehicle.

NOTE: A radiator that has been in use for
some time should not be allowed to stand
empty for any length of time. The radiator
should be immersed in a tank of coolant or
otherwise kept full. If applicable, ensure that
no coolant is allowed to enter the automatic
transaxle oil cooler in the left hand side tank
of the radiator.

Failure to observe this precaution may

result in overheating when the engine is put
back into service. This is caused by internal
deposits in the radiator drying and flaking
and so obstructing the circulation of the
coolant in the system.

TO FLUSH AND CLEAN

(1) Remove the radiator as previously described.
(2) Apply a water hose to the radiator outlet and

reverse flush the radiator until the water flowing from
it is clean.

Cleaning the radiator core from the rear to the front

using a garden hose.

(3) Stand the radiator upright and apply a

stream of water or compressed air to the radiator core
from the rear to [he front. Maintain this procedure
until all dirt and foreign matter is removed from the
radiator core.

(4) With the aid of a light, make a visual check

of the core tubes through the radiator inlet or outlet
fittings. If it is apparent that the tubes are severely
impregnated with flakes of rust it will be necessary to
renew the radiator assembly.
TO REPAIR

The repair procedure described below is only

suitable for holes occurring in the radiator core tubes
that are not bigger than approximately 1 mm.

(1) Suitably mark the area of the leak using a

piece of chalk or similar.

(2) Remove the radiator from the vehicle as

previously described, clean it thoroughly and dry the
damaged area with a hair dryer.

(3) If necessary, carefully cut away or bend the

fins from the tubes to expose the affected area.

NOTE: Do not remove more than 25 mm
total finning from the radiator or cooling
performance will be affected.

(4) Clean the damaged area carefully using a

scraper and wipe clean using a cloth moistened with
petrol.

(5) Apply well mixed Nissan or Holden adhe-

sive part number 21411-J7025, or equivalent, spar-
ingly to the damaged area using a wooden spatula.

(6) Allow the repair to dry in ambient condi-

tions for a minimum of 3 hours before installing the
radiator to the vehicle and testing for leaks. Do not
use heat to promote drying.

TO INSTAL

Installation is a reversal of the removal procedure

with attention to the following points:

Reverse

flushing the radiator using water pressure.

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