2003 DAEWOO MATIZ radiator

1D–8 ENGINE COOLING
DAEWOO M-150 BL2
COOLING SYSTEM DIAGNOSIS
Condition Probable Cause Correction
Engine OverheatsA loss of the coolant.Add the coolant.
A weak coolant solution.Confirm that the coolant solution is a
50/50 mixture of ethylene glycol and
water.
Any dirt, any leaves, or any insects
on the front of the radiator.Clean the front of the radiator.
The leakage from the hoses, the
coolant pump, the heater, the
thermostat housing, the radiator, the
heater core, or the head gasket.Replace any damaged components.
A faulty thermostat.Replace a damaged thermostat.
Retarded ignition timing.Perform an ECM code diagnosis.
Confirm the integrity of the timing
belt.
An improperly operating electric
cooling fan.Replace the electric cooling fan.
Plugged or rotted radiator hoses.Replace any damaged radiator
hoses.
A faulty water pump.Replace a faulty water pump.
A faulty surge tank cap.Replace a faulty surge tank cap.
A cracked or plugged cylinder head
or engine block.Repair the damaged cylinder head or
the damaged engine block.
A faulty radiator.Replace a faulty radiator.
Loss of CoolantA leak in the radiator.Replace a damaged radiator.
A leak in the surge tank or the hose.Replace the surge tank or the hose.
Looseness or damage of radiator
hoses, heater hoses, or connections.Reseat the hoses.
Replace the hoses or the clamps.
Leaks in the coolant pump seal.Replace the coolant pump seal.
Leaks in the coolant pump gasket.Replace the coolant pump gasket.
An improper cylinder head torque.Tighten the cylinder head bolts to
specifications.
Replace the cylinder head gasket, if
needed.
Leaks in the intake manifold, cylinder
head gasket, heater core.Repair or replace any components,
as needed to correct the leak.
Engine Fails to Reach
Normal OperatingThermostat to be stuck open or to be
wrong type.Install a new thermostat of the
correct type and heat range.
Temperature or Cool Air
from the HeaterThe coolant level below the MIN
mark on the surge tank.Add sufficient coolant to raise the
fluid to the specified mark on the
surge tank.

ENGINE COOLING 1D–9
DAEWOO M-150 BL2
REPAIR INSTRUCTIONS
ON–VEHICLE SERVICE
D12D5011
DRAINING AND REFILLING THE
COOLING SYSTEM
Caution: Do not remove the surge tank cap while
the engine and the radiator are hot. Scalding fluid
and steam may be blown out under pressure.
1. Place a pan below the vehicle to catch the draining
coolant.
2. Drain the coolant.
Remove the surge tank cap (1).
Disconnect the lower radiator hose (2).
Caution: Dispose of the used coolant to a used
coolant holding tank to be picked up with the used
oil for disposal. Never pour the used coolant down
the drain. Ethylene glycol antifreeze is an extremely
toxic chemical. Disposing of it into the sewer sys-
tem or the ground water can contaminate the local
environment.
D102D502
3. Connect the lower radiator hose.
4. Clean the cooling system.
Remove all sludge and dirt from inside the surge
tank. And install the surge tank. Refer to “Surge
Tank” in this section (1).

1D–10 ENGINE COOLING
DAEWOO M-150 BL2
D102D503
Add the clean water to the surge tank (2).
5. Run the engine until the thermostat opens. You can
tell the thermostat is open when both radiator hoses
are hot to the touch.
6. Stop the engine and disconnect the lower radiator
hose to drain the coolant.
7. Repeat steps 3 through 6 until the drained water is
clear and free of coolant and rust.
Notice: Never use an antifreeze mixture more concen-
trated than 60 percent antifreeze to 40 percent water.
The solution freezing point increases above this con-
centration.
8. Fill the cooling system through the surge tank with a
mixture of ethylene glycol antifreeze and water. The
mixture must be at least 50 percent antifreeze, but
not more than 60 percent antifreeze for cold weather
operation.
9. Fill the surge tank to the specified MAX fill mark on
the outside of the tank.
10. Install the surge tank cap.
D102D504
SURGE TANK
Removal Procedure
Caution: To prevent personal injury, do not remove
the surge tank cap while the engine and the radiator
are hot, because the heat causes the system to re-
main under pressure scalding fluid and steam may
be blown out under pressure.
1. Drain the engine coolant to below the level of the
surge tank.
2. Remove the surge tank.
Loosen the overflow hose clamps and disconnect
the overflow hoses from the surge tank (1).
Remove the surge tank (2).
3. Clean the inside and the outside of the surge tank and
the surge tank cap with soap and water.
4. Rinse the surge tank and the cap thoroughly.
5. Check the surge tank and the cap for crack or other
damage.

ENGINE COOLING 1D–11
DAEWOO M-150 BL2
D102D505
Installation Procedure
1. Install the surge tank to the vehicle.
Install the surge tank with pressing down (1).
Connect the overflow hoses to the surge tank (2).
2. Secure the overflow hoses to the surge tank with the
hose clamps.
3. Fill the surge tank with coolant to the MAX mark.
D102D506
ELECTRIC COOLING FAN
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the electric cooling fan assembly.
Disconnect the cooling fan electrical connector (1).
Remove the bolts (2).
Remove the electric cooling fan assembly (3).
3.5–4.5 Nm
D12D507A
Installation Procedure
1. Install the electric cooling fan assembly with the bolts.
Tighten
Tighten the bolts to 3.5–4.5 Nm (31–40 lb-in).
2. Connect the cooling fan electrical connector.
3. Connect the negative battery cable.
D12D5081
RADIATOR
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the lower radiator hose and drain the en-
gine cooling system. Refer to “Draining and Refilling
the Cooling System” in this section.
3. Disconnect the upper radiator hose and the surge
tank hose.
Loosen the upper radiator hose clamp and discon-
nect the upper radiator hose (1).
Loosen the surge tank hose clamp and disconnect
the surge tank hose (2).

1D–12 ENGINE COOLING
DAEWOO M-150 BL2
D12D5091
4. Remove the electric cooling fan.
Refer to “Electric Cooling Fan” in this section.
5. Remove the radiator.
Remove the bolts (1).
Remove the radiator support brackets (2).
Remove the radiator (3).
6. Check the radiator for breaking, clog or other dam-
age.
Important: The radiator still contains a substantial
amount of coolant. Drain the remainder of the coolant
from the radiator into a drain pan.
D12D5101
Installation Procedure
1. Install the radiator with the mounting bolts (1) and the
support brackets (2).
Tighten
Tighten the support bracket bolts to 3.5–4.5 Nm
(31–40 lb-in).
2. Install the electric cooling fan.
Refer to “Electric Cooling Fan” in this section.
D12D5111
3. Connect the upper radiator hose to the radiator (1).
4. Connect the surge tank hose to the radiator (2).
5. Secure each hose with hose clamps.
6. Refill the engine cooling system. Refer to “Draining
and Refilling the Cooling System” in this section.
7. Connect the negative battery cable.
D102D512
THERMOSTAT (TYPICAL)
Removal Procedure
Caution: To prevent personal injury, do not remove
the surge tank cap while the engine and the radiator
are hot because the heat causes the system to re-
main under pressure. Scalding fluid and steam may
be blown out under pressure.
1. Remove air filter assembly. Refer to Section 1B,
SOHC Engine Mechanical.
2. Disconnect the lower radiator hose and drain the
coolant. Refer to “Drain and Refilling the Cooling Sys-
tem”
3. Disconnect the upper radiator hose.

ENGINE COOLING 1D–13
DAEWOO M-150 BL2
Loosen the hose clamp (1).
Disconnect the upper radiator hose (2).
D102D513
4. Remove the thermostat.
Remove the bolts (1).
Remove the thermostat housing (2).
Remove the thermostat with the gasket (3).
5. Check the gasket for crack or other damage.
6. Inspect the valve seat for foreign matter that could
prevent the valve from seating properly.
7. Inspect the thermostat for proper operation. Refer to
“Thermostat Test” in this section.
8–15 Nm
D12D514A
Installation Procedure
1. Install the thermostat with the bolts and the thermo-
stat housing.
Tighten
Tighten the mounting bolts to 8–15 Nm (71–130
lb-in).
2. Secure the upper radiator hose to the thermostat
housing with a hose clamp.
3. Refill the engine cooling system. Refer to “Draining
and Refilling the Cooling System” in this section.
MAA1D010
THERMOSTAT (EURO III)
Removal Procedure
Caution: To prevent personal injury, do not remove
the surge tank cap while the engine and the radiator
are hot because the heat causes the system to re-
main under pressure. Scalding fluid and steam may
be blown out under pressure.
1. Remove air filter assembly. Refer to Section 1B,
SOHC Engine Mechanical.
2. Disconnect the lower radiator hose and drain the
coolant. Refer to “Drain and Refilling the Cooling Sys-
tem”
3. Disconnect the upper radiator hose.

1D–14 ENGINE COOLING
DAEWOO M-150 BL2
MAA1D020
4. Remove the thermostat.
Remove the bolts.
Remove the thermostat housing.
Remove the thermostat with the gasket.
5. Check the gasket for crack or other damage.
6. Inspect the valve seat for foreign matter that could
prevent the valve from seating properly.
7. Inspect the thermostat for proper operation. Refer to
“Thermostat Test” in this section.
MAA1D011
Installation Procedure
1. Install the thermostat with the bolts and the thermo-
stat housing.
Tighten
Tighten the mounting bolts to 8–15 Nm (71–130
lb-in).
2. Secure the upper radiator hose to the thermostat
housing with a hose clamp.
3. Refill the engine cooling system. Refer to “Draining
and Refilling the Cooling System” in this section.
4. Install the air filter assembly. Refer to Section 1B,
SOHC Engine Mechanical.
D102D515
COOLANT TEMPERATURE SENSOR
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the lower radiator hose and drain the
coolant. Refer to “Draining and Refilling the Cooling
System” in this section.
3. Remove the coolant temperature sensor.
Disconnect the electrical connector (1).
Remove the coolant temperature sensor (2).
D12D516A
10 Nm
Installation Procedure
1. Install the coolant temperature sensor into the
threaded hole in the intake manifold.
Tighten
Tighten the coolant temperature sensor to 10 Nm
(89 lb-in).
Connect the electrical connector to the coolant
temperature sensor (1).
2. Connect the lower radiator hose and refill the coolant.
Refer to “Draining and refilling the cooling system” in
this section.
3. Connect the negative battery cable.

ENGINE COOLING 1D–15
DAEWOO M-150 BL2
D102D517
ENGINE COOLANT TEMPERATURE
SENSOR
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the lower radiator hose and drain the
coolant “Draining and Refilling the Cooling System” in
this section.
3. Remove the engine coolant temperature (ECT) sen-
sor.
Disconnect the electrical connector (1).
Remove the ECT sensor (2).
D12D518A
20 Nm
Installation Procedure
1. Install the ECT sensor.
Tighten
Tighten the ECT sensor to 20 Nm (15 lb-ft).
Connect the electrical connector to the ECT sen-
sor (1).
2. Connect the lower radiator hose and refill the coolant.
Refer to “Draining and Refilling the Cooling System”
in this section.
3. Connect the negative battery cable.
D102B533
COOLANT PUMP
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the lower radiator hose and drain the
coolant. Refer to “Draining and Refilling the Cooling
System” in this section.
3. Remove the timing belt. Refer to Section 1B, Engine
Mechanical.
4. Remove the rear timing belt cover.
Remove the bolts (1).
Remove the rear timing belt cover (2).
D102D519
5. Remove the coolant pump.
Remove the nuts (1).
Remove the bolts (2).
Remove the coolant pump (3).
Remove the gasket.
Notice: Remove the coolant pump as shown figure (a).