cooling system DAEWOO MATIZ 2003 Service Repair Manual

1A–8 GENERAL ENGINE INFORMATION
DAEWOO M-150 BL2
GENERAL DIAGNOSIS (Cont’d)
 
 Condition
 
 Probable cause
 
 Correction
Engine Surging
(Engine power makes
fluctuation in a fixedOthers
Leak of the intake manifold
gasket.
Clean or replace the gasket.
speed and speed
changes without
operating the
accelerating pedal.)
Leakage of the vacuum hose.
Connect the hose correctly
or replace it.
Excessive Detonation
(According to theOverheated
Engine
Refer to “Overheat” in this
page.
Refer to “Overheat” in this
page.
opening range of
throttle valve,Malfunction of
Abnormal spark plug.
Replace the spark plug.
knocking sound of
metallic is made withIgnition System
Poor ignition timing.
Adjust the ignition timing.metallic is made with
abnormal explosion.)

Electric leakage or poor
connection of the high tension
cable.
Connect the cable correctly
or replace it.
Malfunction of
Fuel System
Clogged or contaminated fuel
filter and fuel pipe.
Clean or replace the fuel
filter and the fuel pipe.
Others
Leak of the intake manifold
gasket.
Replace the gasket.

Excessive carbon deposit due
to abnormal combustion.
Remove the carbon.
OverheatMalfunction of
Lack of coolant.
Refill coolant.
Cooling System
Malfunction of the thermostat.
Replace the thermostat.

Malfunction of the cooling fan.
Check or replace the cooling
fan.

Poor water pump
performance.
Replace the pump.

Clogged or leaky radiator.
Clean, repair or replace the
radiator.
Malfunction of
Lubrication
Poor engine oil.
Replace engine oil with the
specified one.
System
Blocking oil filter or strainer.
Clean or replace the oil filter
or the strainer.

Lack of engine oil.
Refill oil.

Poor oil pump performance.
Replace or repair the pump.

Leakage of oil.
Repair.
Other
Damaged cylinder head
gasket.
Replace the gasket.
Poor Fuel
ConsumptionDecline of
Compression
Pressure
Refer to “Page 1A–5”.
Refer to “Page 1A–5”.
Malfunction of
Fuel System
Leakage of the fuel tank or
the fuel pipe.
Repair or replace the fuel
tank or the fuel pipe.

GENERAL ENGINE INFORMATION 1A–9
DAEWOO M-150 BL2
GENERAL DIAGNOSIS (Cont’d)
 Condition Probable cause Correction
Poor FuelMalfunction of
Improper ignition timing.
Adjust the ignition timing.
ConsumptionIgnition System
Abnormal spark plug
(Excessive carbon deposit,
inadequate gap, burnt
electrode).
Replace the plug.

Electric leakage or poor
connection of the high
tension cable.
Connect the cable normally
or replace it.
Malfunction of
Cooling System
Malfunction of the
thermostat.
Replace the thermostat.
Others
Improperly installed valve.
Repair or replace the valve.

Slipping clutch.
Repair or replace the clutch.

Low pressure of tires.
Adjust the pressure of tires.
ExcessiveLeakage of
Loosened oil drain plug.
Tighten the plug.
Consumption of
Engine OilEngine Oil
Loosened oil pan bolt.
Tighten the bolt.Engine Oil

Loosened oil filter.
Tighten the filter.

Loosened oil pressure
switch.
Tighten the switch.

Leakage of camshaft front oil
seal.
Replace the seal.

Leakage of crankshaft front
oil seal.
Replace the seal.

Leakage at the cylinder head
cover gasket.
Replace the gasket.

Damage of the cylinder head
gasket.
Replace the gasket.
Oil Mixing in
Combustion
Stuck piston ring.
Remove carbon and replace
the ring.
Chamber
Worn piston or cylinder.
Replace the piston or the
cylinder.

Worn piston ring or ring
groove.
Replace the piston or ring.

Inadequate position of the
piston ring cutting part.
Adjust the position.

Abrasion or damage of the
valve system.
Replace the valve system.
Low Oil PressureMalfunction of
Lubrication
Inadequate oil viscosity.
Replace with the specified
one.
System
Loosening of the oil pressure
switch.
Tighten the switch.

Lack of engine oil.
Refill oil.

Blocking oil strainer.
Clean the strainer.

1A–14 GENERAL ENGINE INFORMATION
DAEWOO M-150 BL2
SPECIFICATIONS
GENERAL SPECIFICATIONS
 Application Description
  Maximum Speed 144 km/h (90 mph)
 Vehicle Capacity Gradeability 0.420 tan θ
 
Vehicle Capacity
 Minimum Turning Radius 4.5 m (14.8 ft)
  Bore × Stroke 68.5 × 72.0 mm (2.70 × 2.83 inch)
  Displacement 796 cm3 (48.6 in3)
  Compression Ratio 9.3 : 1
  Maximum Power 37.5 KW (6,000 rpm)
 
Engine Information
 Maximum Torque 68.6 Nm (50.59 lb-ft) (at 4,600 rpm)
Ignition Timing (Ignition Sequence)5 BTDC (1–3–2) / 10 BTDC (1–3–2)   
Air Conditioning System (ON)
 
1,000 ± 50 rpm  Idle Speed Air Conditioning System (OFF) 950 rpm  Engine Overhead Cam L–3 
 
 
 Ignition Type
 
 Direct Ignition System (DIS) /
High Energy Ignition (HEI)
  Distributor Optical Sensor Type
  Starter SD 80
   Unleaded BPR5EY–11, RN9YC4, WR8DCX
  Spark–Plug Leaded BPR5EY, RN9YC, WR8DC
  Fuel Injection Type MPI
  Fuel Pump Electric Motor Pump
Engine Part TypeFuel FilterCartridge Engine Part Type 
Lubricating Type
 
Forced Feed Type  Oil Pump Rotary Pump Type  Cooling Type Forced Water Circulation  Radiator Cross – Flow  Water Pump Centrifugal  Thermostat Pellet Type
  Air Cleaner Element Non Woven Fablic
  Muffler Catalytic Converter, Closed Circuit
  Battery MF
Engine PartEngine OilSJ Grade
SAE 5W30, SAE 10W30, SAE 15W40
CapacityRefrigerantFour Seasons   
Engine Disassembly
 
3.0 L (3.17 qt)   Oil Change (Including filter) 2.7 L (2.85 qt)  Engine Oil Oil Change (Not including filter) 2.5 L (2.64 qt)   Oil Level Gauge 1 L (1.06 qt) (MIN to MAX)  Coolant 3.8 L (4.02 qt) Engine Information Battery 12V–35 AH, 246 CCA
 Engine Information  

Generator

65 A
  Starter 0.8 kW
   Output Capacity 90 – 133 Lph
  Fuel Pump Output Pressure 380 kPa (55.1 Psi)
  Fuel Tank Capacity 35 L (9.2 gal), 38 L (10 gal)

SOHC ENGINE MECANICAL 1B–11
DAEWOO M-150 BL2
The measured value of valve clearance should meet the
specified value. If not, adjust the valve clearance.
Important: In case of hot engine, warm up the engine
until the electric cooling fan begins to work and stop the
engine to adjust the clearance with 20–30 minutes there
from.
Unit : mm (in.)
Item Specified value

Intake0.15±0.02
(0.0059±0.0008)

Valve
Cold
Exhaust0.32±0.02
(0.0126±0.0008)


Valve
Clearance
Intake0.25±0.02
(0.0098±0.0008)


Hot
Exhaust0.42±0.02
(0.0165±0.0008)
8. When adjusting the valve clearance, loosen the ad-
just nut (k) and then tighten or loosen the adjust rod (l)
properly.
D102B307
IGNITION TIMING CHECK AND
ADJUSTMENT (TYPICAL)
Note: Ignition timing could not be adjusted for Direct
Ignition System (Euro Stage III).
Check and adjust the ignition timing in the following pro-
cedures:
1. Warm up the engine to the normal operating tempera-
ture.
2. Turn off the lamp and audio system and shift the shift
gear lever in Neutral.
D12B3081
3. Connect terminal A and terminal C of ALDL connec-
tor using the wire (m) or connect the scan tool (n) with
ALDL connector.
4. Connect the timing light (o) with No. 1 cylinder high
tension cable and check the specified value for the
ignition timing, flashing notch on the crankshaft
pulley.
Item Specified Value
Ignition timing – 950rpm10 BTDC
Important: In flashing the timing light, if crankshaft
pulley notch (p) is matched with the mark (10) for timing
check, the ignition timing is 10 BTDC.
D102B309

DAEWOO M-150 BL2
SECTION 1D
ENGINE COOLING
CAUTION: Disconnect the negative battery cable before removing or installing any electrical unit or when a
tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable
will help prevent personal injury and damage to the vehicle. The ignition must also be in B unless otherwise
noted.
TABLE OF CONTENTS
Description and Operation 1D-2. . . . . . . . . . . . . . . . . .
General Description 1D-2. . . . . . . . . . . . . . . . . . . . . . .
Radiator 1D-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Surge Tank 1D-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant Pump 1D-3. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermostat 1D-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electric Cooling Fan 1D-3. . . . . . . . . . . . . . . . . . . . . . .
Engine Coolant Temperature Sensor 1D-4. . . . . . . . .
Coolant Temperature Sensor 1D-4. . . . . . . . . . . . . . . .
Component Locator 1D-5. . . . . . . . . . . . . . . . . . . . . . . .
Coolant Hose and Components 1D-5. . . . . . . . . . . . .
Radiator/Fan 1D-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diagnostic Information and Procedure 1D-7. . . . . . .
Coolant Leaks Test 1D-7. . . . . . . . . . . . . . . . . . . . . . . .
Surge Tank Cap Test 1D-7. . . . . . . . . . . . . . . . . . . . . . .
Thermostat Test 1D-7. . . . . . . . . . . . . . . . . . . . . . . . . . . Cooling System Diagnosis 1D-8. . . . . . . . . . . . . . . . . .
Repair Instructions 1D-9. . . . . . . . . . . . . . . . . . . . . . . . .
On-Vehicle Service 1D-9. . . . . . . . . . . . . . . . . . . . . . . . . .
Draining and Refilling the Cooling System 1D-9. . . .
Surge Tank 1D-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electric Cooling Fan 1D-11. . . . . . . . . . . . . . . . . . . . . .
Radiator 1D-11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermostat (Typical) 1D-12. . . . . . . . . . . . . . . . . . . . . .
Thermostat (Euro III) 1D-13. . . . . . . . . . . . . . . . . . . . . .
Coolant Temperature Sensor 1D-14. . . . . . . . . . . . . . .
Engine Coolant Temperature Sensor 1D-15. . . . . . . .
Coolant Pump 1D-15. . . . . . . . . . . . . . . . . . . . . . . . . . .
Specifications 1D-17. . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Specifications 1D-17. . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 1D-18. . . . . . . . . .

1D – 2 ENGINE COOLING
DAEWOO M-150 BL2
DESCRIPTION AND OPERATION
GENERAL DESCRIPTION
The cooling system maintains the engine temperature at
an efficient level during all engine operating conditions.
When the engine is cold the cooling system cools the
engine slowly or not at all. This slow cooling of the en-
gine allows the engine to warm up quickly.
The cooling system includes a radiator(a) and cooling
fan(b), a thermostat and housing(c), a coolant pump(d),
a coolant pump drive belt and coolant hose. The timing
belt drives the coolant pump.
All components must function properly in order for the
cooling system to operate. The coolant pump draws the
coolant from the radiator. The coolant then circulates
through water jackets in the engine block and the cylin-
der head, distributor case(e), throttle body(f). When the
coolant reaches the operating temperature of the ther-
mostat, the thermostat opens. The coolant then goes
back to the radiator where it cools.
This system directs some coolant through the hoses to
the heater core(g). This provides for heating and de-
frosting. The surge tank(h) is connected to the radiator
and throttle body to recover the coolant displaced by ex-
pansion from the high temperatures. The surge tank
maintains the correct coolant level.
The cooling system for this vehicle has no radiator cap
and drain cock. The coolant is added to the cooling sys-tem through the surge tank. To drain the cooling system,
disconnect the lower radiator hose and drain the cool-
ant.
RADIATOR
This vehicle has a lightweight tube-and-fin aluminum ra-
diator.
SURGE TANK
The surge tank is a transparent plastic reservoir, similar
to the windshield washer reservoir.
The surge tank is connected to the radiator and throttle
body by a hose. As the vehicle is driven, the engine cool-
ant heats and expands. The portion of the engine cool-
ant displaced by this expansion flows from the radiator
into the surge tank. The air trapped in the radiator is de-
gassed into the surge tank.
When the engine is stops, the engine coolant cools and
contracts. The displaced engine coolant is then drawn
back into the radiator. This keeps the radiator filled with
the coolant to the desired level at all times and increases
the cooling efficiency.
Maintain the coolant level between the MIN and the
MAX marks on the surge tank when the system is cold.
D102D001

ENGINE COOLING 1D–3
DAEWOO M-150 BL2
COOLANT PUMP
The belt-driven centrifugal coolant pump consists of an
impeller, a drive shaft, and a belt pulley.
The impeller is supported by a completely sealed bear-
ing.
The coolant pump is serviced as an assembly and,
therefore, cannot be disassembled.
THERMOSTAT
A wax pellet-type thermostat controls the flow of the en-
gine coolant through the engine cooling system. The
thermostat(i) is mounted in the thermostat housing.
The thermostat stops the flow of the engine coolant from
the engine to the radiator in order to provide faster
warm-up, and to regulate the coolant temperature. The
thermostat remains closed while the engine coolant is
cold, preventing circulation of the engine coolant
through the radiator. At this point, the engine coolant is
allowed to circulate only throughout the heater core to
warm it quickly and evenly.
As the engine warms, the thermostat opens. This allows
the engine coolant to flow through the radiator, where
the heat is dissipated through the radiator. This opening
and closing of the thermostat permits enough engine
coolant to enter the radiator to keep the engine within
proper engine temperature operating limits.
The wax pellet in the thermostat is hermetically sealed in
a metal case(j). The wax element of the thermostat ex-
pands when it is heated and contracts when it is cooled.
As the vehicle is driven and the engine warms, the en-
gine coolant temperature increases. When the engine
coolant reaches a specified temperature, the wax pellet
element in the thermostat expands and exerts pressure
against the metal case, forcing the valve open. This al-
lows the engine coolant to flow through the engine cool-
ing system and cool the engine.
As the wax pellet cools, the contraction allows a spring
to close the valve.
The thermostat begins to open at 82
C (180
F) and is
fully open at 95
C (203
F). The thermostat closes at
80
C (176
F).
D102D002
ELECTRIC COOLING FAN
Caution: Keep hands, tools, and clothing away from
the engine cooling fans to help prevent personal in-
jury. This fan is electric and can turn ON whether or
not the engine is running.
Caution: If a fan blade is bent or damaged in any
way, no attempt should be made to repair or reuse
the damaged part. A bent or damaged fan assembly
should always be replaced with a new one.
The cooling fans are mounted behind the radiator in the
engine compartment. The electric cooling fans increase
the flow of air across the radiator fan and across the
condenser on air conditioner (A/C)-equipped vehicles.
This helps to speed cooling when the vehicle is at idle or
moving at low speeds.
D102D003

1D–4 ENGINE COOLING
DAEWOO M-150 BL2
The main fan size is 320 mm (12.6 in.) in diameter with
seven blades(k) to aid the air flow through the radiator
and the condenser. An electric motor(l) attached to the
radiator support drives the fan.
A/C OFF or Non-A/C Model
The cooling fan is actuated by the electronic control
module (ECM) using a low speed cooling fan relay
and a high speed cooling fan relay. On A/C equipped
vehicles, a series/parallel cooling fan relay is also
used.
The ECM will turn the cooling fan on at low speed
when the coolant temperature reaches 93
C (199
F)
and high speed at 100
C (212
F).
The ECM will change the cooling fan from high speed
to low speed at 97
C (207
F) and turn the cooling
fans off at 90
C (194
F).
A/C ON
The ECM will only turn the cooling fan on at high
speed when the A/C system is on regardless of any
condition.
ENGINE COOLANT TEMPERATURE
SENSOR
The engine coolant temperature (ECT) sensor (n) uses
a thermistor to control the signal voltage to the engine
control module (ECM).
D102D004
COOLANT TEMPERATURE SENSOR
The coolant temperature sensor(m) controls the instru-
ment panel temperature indicator. The coolant tempera-
ture sensor is located on the distributor case with the
ECT sensor on an SOHC engine.

ENGINE COOLING 1D–7
DAEWOO M-150 BL2
DIAGNOSTIC INFORMATION AND PROCEDURE
COOLANT LEAKS TEST
1. Remove the surge tank cap after the engine cools.
2. Check the coolant level.
3. Install a suitable cooling system pressure tester(b) to
the surge tank filler neck using the adapter(a) and
pressurize (110–120 kPa (16.0–17.4 psi)).
4. Check the coolant leaks on the hoses and connec-
tions during 2 minutes.
5. If the leak is checked, replace the parts or repair the
connections.
D102D301
SURGE TANK CAP TEST
The surge tank cap(c) is equipped with the pressure
valve(d) and the vacuum valve(e). Therefore, the surge
tank cap maintains proper pressure. And The surge tank
cap protects the system from high-pressure by opening
a pressure valve, and protects the coolant hoses from
collapsing because of a vacuum.
1. Wash any sludge from the surge tank cap and the
valve seat of the vacuum pressure valve for the surge
tank cap.
2. Check for any damage or deformity to the vacuum
pressure valve for the surge tank cap. If any damage
or deformity is found, replace the cap.
3. Install a suitable cooling system pressure tester(b) to
the cap using the Adapter(a).
4. Pull the vacuum pressure valve to the open position.
If the surge tank cap does not seal properly, replace
the surge tank cap.
5. Pressurize the cap to 90 to 120kPa (13 to 17psi).
6. Wait 10 seconds and check the pressure held by the
tank cap tester.
7. If the pressure held by the cooling system pressure
tester falls below 80kPa (11.6psi) replace the surge
tank cap.
D102D302
THERMOSTAT TEST
1. Remove the thermostat(f) from the vehicle. Refer
to“Thermostat” in this section.
2. Make sure the valve spring is tight when the thermo-
stat is fully closed. If the spring is not tight, replace the
thermostat.
3. Suspend the thermostat and a thermometer in a pan
of 50/50mixture of ethylene glycol and water. Do not
let the thermostat or the thermometer rest on the bot-
tom of the pan because the uneven concentration of
heat on the bottom could result in inaccurate temper-
ature measurements.
4. Heat the pan on a burner.
5. Use the thermometer to measure the temperature of
the heated solution.
6. The thermostat should begin to open at 82°C (180°F)
and it should be fully open at 95°C (203.4°F) and it
should be fully close at 80°C (176.4°F). If it does not
open or close at these temperature, replace the ther-
mostat. Also, the thermostat rod’s stroke from the ini-
tially open to the fully open should be 8mm (0.31 in.).
D102D303

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.