radiator cap DAEWOO LACETTI 2004 Service Repair Manual

GENERAL INFORMATION 0B – 5
DAEWOO V–121 BL4
Cooling System
Application1.4L DOHC1.6L DOHC1.8L DOHC
Cooling TypeForced Water
Circulation


Radiator TypeCross–flow


Water Pump TypeCentrifugal


Thermostat TypePellet Type


Coolant Capacity7.0L (7.49 qts)7.2L (7.6 qts)7.4L (7.8 qts)
Electric System
Application1.4L DOHC1.6L DOHC1.8L DOHC
Battery12V–55 AH


610 CCA
(Cold Cranking Amps)


Alternator85 Amps
95 Amps
Starter1.2 KW
1.4 KW
No–Load Test @ 12.2
volts
Drive Pinion Speed at :90 Amps Max
Min. 2,600 rpm


85 Amps Max
Min. 2,550 rpm

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 53
DAEWOO V–121 BL4
39. Connect the lower radiator hose to the coolant pipe.
40. Connect the upper radiator hose to the thermostat
housing.
41. Connect the surge tank coolant hose to the radia-
tor.
42. Connect the heater inlet hose to the cylinder head.
43. Connect the heater outlet hose to the coolant pipe.
44. Connect the coolant surge tank hose to the coolant
pipe.
45. Connect the surge tank coolant hose to the throttle
body.
46. Connect the throttle cable to the throttle body and
the intake manifold bracket.
47. Install the fuel pump fuse.
48. Connect the negative battery cable.
49. Refill the engine crankcase with engine oil.
50. Refill the engine coolant system. Refer to Section
1D, Engine Cooling.
51. Bleed the power steering system. Refer to Section
6A, Power Steering System.
52. Refill the A/C refrigerant system, if equipped. Refer
to Section 7B, Manual Control Heating, Ventilation,
and Air Conditioning System.
53. Install the hood. Refer to Section 9R, Body Front
End.
PISTONS AND RODS
Tools Required
KM–427 Piston Pin Service Set
KM 470–B Angular Torque Gauge
Removal Procedure
1. Remove the cylinder head with the intake manifold
and the exhaust manifold attached. Refer to ”Cylin-
der Head and Gasket” in this section.
2. Remove the oil pan. Refer to ”Oil Pan” in this sec-
tion.
3. Remove the oil suction pipe bolts.
4. Remove the oil suction pipe.
5. Move the piston to the bottom of the piston stroke.
6. Mark the connecting rod cap for position.
7. Remove the connecting rod cap bolts.
8. Remove the connecting rod cap and the lower con-
necting rod bearing.
9. Remove the upper piston connecting rod bearing.
10. Ridge ream the cylinder wall.

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 LOCK unless otherwise noted.
TABLE OF CONTENTS
SPECIFICATIONS1D–2 . . . . . . . . . . . . . . . . . . . . . . . . . .
Capacity 1D–2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 1D–2. . . . . . . . . . .
SPECIAL TOOLS1D–2 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Tools Table 1D–2. . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS1D–3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermostat Test 1D–3. . . . . . . . . . . . . . . . . . . . . . . . . . .
Surge Tank Cap Test 1D–3. . . . . . . . . . . . . . . . . . . . . . .
Cooling System Diagnosis 1D–4. . . . . . . . . . . . . . . . . .
COMPONENT LOCATOR1D–5 . . . . . . . . . . . . . . . . . . . .
Radiator/Fan 1D–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Water Pump/Thermostat (1.4L/1.6L DOHC) 1D–6. . .
Water Pump/Thermostat (1.8L DOHC) 1D–7. . . . . . .
MAINTENANCE AND REPAIR1D–8 . . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 1D–8. . . . . . . . . . . . . . . . . . . . . Draining and Refilling the Cooling System 1D–8. . . . .
Thermostat (1.4L/1.6L DOHC) 1D–9. . . . . . . . . . . . . . .
Thermostat (1.8L DOHC) 1D–10. . . . . . . . . . . . . . . . . .
Water Pump 1D–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electric Cooling Fan – Main or Auxiliary 1D–13. . . . . .
Surge Tank 1D–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Radiator 1D–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION1D–18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Description 1D–18. . . . . . . . . . . . . . . . . . . . . . .
Radiator 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Surge Tank 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Water Pump 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Thermostat 1D–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electric Cooling Fan 1D–19. . . . . . . . . . . . . . . . . . . . . . .
Engine Block Heater 1D–19. . . . . . . . . . . . . . . . . . . . . .

1D – 2IENGINE COOLING
DAEWOO V–121 BL4
SPECIFICATIONS
CAPACITY
ApplicationDescription
Coolant in the Cooling System
(1.4L/1.6L DOHC MPFI System)7.0L (1.85 gal) for automatic transaxle
7.0L (1.85 gal) for manual transaxle
Coolant in the Cooling System
(1.8L DOHC MPFI System)7.1L (1.88 gal) for automatic transaxle
7.1L (1.88 gal) for manual transaxle
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Water Pump Mounting Bolts (1.4L/1.6L DOHC)10–89
Water Pump Mounting Bolts (1.8L DOHC)2518–
Fan Assembly Mounting Bolts4–35
Fan Motor Nut3.2–28
Fan Motor Retaining Screws4–35
Radiator Retaining Bolts, Upper Left and Upper Right8–71
Surge Tank Attaching Bolt5–44
Thermostat Housing Mounting Bolts (1.6L DOHC)2015–
Thermostat Housing Mounting Bolts (1.8L DOHC)1511–
SPECIAL TOOLS
SPECIAL TOOLS TABLE
KM–471
Adapter

1D – 4IENGINE COOLING
DAEWOO V–121 BL4
COOLING SYSTEM DIAGNOSIS
Engine Overheats
ChecksAction
Check for a loss of the coolant.Add the coolant.
Check for a weak coolant solution.Confirm that the coolant solution is a 50/50 mixture of eth-
ylene glycol and water.
Check the front of the radiator for any dirt, any leaves, or
any insects.Clean the front of the radiator.
Check for leakage from the hoses, the coolant pump, the
heater, the thermostat housing, the radiator, the core
plugs, or the head gasket.Replace any damaged components.
Check for a faulty thermostat.Replace a damaged thermostat.
Check for retarded ignition timing.Perform an ECM code diagnosis. Confirm the integrity of
the timing belt.
Check for an improperly operating electric cooling fan.Replace the electric cooling fan.
Check for radiator hoses that are plugged or rotted.Replace any damaged radiator hoses.
Check for a faulty water pump.Replace a faulty water pump.
Check for a faulty surge tank cap.Replace a faulty surge tank cap.
Check for a cylinder head or an engine block that is
cracked or plugged.Repair the damaged cylinder head or the damaged engine
block.
Loss of Coolant
ChecksAction
Check for a leak in the radiator.Replace a damaged radiator.
Check for a leak in the following locations:
S Surge tank.
S Hose.Replace the following parts, as needed:
S Surge tank.
S Hose.
Check for loose or damaged radiator hoses, heater hoses,
and connections.Reseat the hoses.
Replace the hoses or the clamps.
Check for leaks in the coolant pump seal.Replace the coolant pump seal.
Check for leaks in the coolant pump gasket.Replace the coolant pump gasket.
Check for an improper cylinder head torque.Tighten the cylinder head bolts to specifications.
Replace the cylinder head gasket, if needed.
Check for leaks in the following locations:
S Intake manifold.
S Cylinder head gasket.
S Cylinder block plug.
S Heater core.
S Radiator drain plug.Repair or replace any components, as needed, to correct
the leak.
Engine Fails to Reach Normal Operating Temperature or Cool Air
from the Heater
ChecksAction
Check to determine if the thermostat is stuck open or is the
wrong type of thermostat.Install a new thermostat of the correct type and heat range.
Check the coolant level to determine if it is below the MIN
mark on the surge tank.Add sufficient coolant to raise the fluid to the specified
mark on the surge tank.

1D – 8IENGINE COOLING
DAEWOO V–121 BL4
MAINTENANCE AND REPAIR
ON–VEHICLE SERVICE
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. Remove the surge tank cap.
3. Unplug the drain cock.
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 system or the
ground water can contaminate the local environment.
4. Catch the escaping fluid in a drain pan.
5. Remove all sludge and dirt from inside the surge
tank. Refer to ”Surge Tank” in this section.
6. Plug the drain cock.
7. Add the clean water to the surge tank.
8. Fill the tank slowly so that the upper reservoir hose
remains above the water line. This allows the air
inside the cooling system to escape.
9. Start the engine.
10. Run the engine until the thermostat opens. You can
tell the thermostat is open when both radiator
hoses are hot to the touch.
11. Stop the engine.
12. Repeat Steps 1 through 9 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 concentration.
13. 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.
14. Fill the surge tank to the specified MAX fill mark on
the outside of the tank.

ENGINE COOLING 1D – 9
DAEWOO V–121 BL4
THERMOSTAT (1.4L/1.6L DOHC)
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 remain
under pressure. Scalding fluid and steam may be
blown out under pressure.
1. Drain the coolant. Refer to ”Draining and Refilling
the Cooling System” in this section.
2. Loosen the hose clamp on the upper radiator hose
at the thermostat housing.
3. Disconnect the upper radiator hose from the ther-
mostat housing.
4. Loosen the clamp on the bypass hose.
5. Disconnect the bypass hose from the thermostat
housing.
6. Remove the mounting bolts that hold the thermo-
stat housing to the cylinder head.
7. Remove the thermostat housing from the head.
8. Remove the O–ring seal from the head.
9. Check the valve seat for foreign matter that could
prevent the valve from seating properly.
10. Check the thermostat for proper operation. Refer to
”Thermostat Test” in this section.
11. Clean the thermostat housing and the cylinder head
mating surfaces.
Installation Procedure
1. Coat the sealing surface of a new O–ring seal with
Lubriplater®.
2. Install a new O–ring seal into the recess in the cyl-
inder head.
3. Secure the thermostat housing to the cylinder head
with the mounting bolts.
Tighten
Tighten the thermostat housing mounting bolts to 20
NSm (15 lb–ft).

1D – 10IENGINE COOLING
DAEWOO V–121 BL4
4. Connect the upper radiator hose to the thermostat
housing.
5. Secure the upper radiator hose to the thermostat
housing with a hose clamp.
6. Connect the bypass hose to the thermostat hous-
ing.
7. Secure the bypass hose with a hose clamp.
8. Refill the engine cooling system. Refer to ”Draining
and Refilling the Cooling System” in this section.
THERMOSTAT (1.8L DOHC)
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 remain
under pressure. Scalding fluid and steam may be
blown out under pressure.
1. Drain the coolant. Refer to ”Draining and Refilling
the Cooling System” in this section.
2. Loosen the hose clamp on the upper radiator hose
at the thermostat housing.
3. Disconnect the upper radiator hose from the ther-
mostat housing.
4. Remove the mounting bolts that hold the thermo-
stat housing to the cylinder head.
5. Remove the thermostat housing from the cylinder
head.
6. Remove the seal ring from the thermostat housing.
7. Remove the thermostat from the thermostat hous-
ing by pressing the thermostat mounting flange
downward and then rotating the flange clockwise.
8. Inspect the valve seat for foreign matter that could
prevent the valve from sealing properly.
9. Inspect the thermostat for proper operation. Refer
to ”Thermostat Test” in this section.
10. Clean the thermostat housing and the cylinder head
mating surfaces.

1D – 14IENGINE COOLING
DAEWOO V–121 BL4
Tighten
Tighten the fan motor retaining screws to 4 NSm (35
lb–in).
3. Turn over the fan shroud assembly.
4. Install the fan to the fan shroud assembly with the
single nut in the center of the fan hub.
Tighten
Tighten the fan motor nut to 3.2 NSm (28 lb–in).
5. Install the fan shroud assembly to the radiator.
Important : Be careful to seat the mounting post on the
fan shroud into the socket at the radiator left tank. Be sure
to slip the tab at the bottom edge of the shroud into the re-
taining clip near the center of the radiator.
6. Secure the shroud to the top of the radiator with the
mounting bolts.
Tighten
Tighten the fan assembly mounting bolts to 4 NSm (35
lb–in).
7. Connect the cooling fan electrical connector.
8. Connect the negative battery cable.
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. Loosen the return hose clamp and disconnect the
return hose from the top of the surge tank.

1D – 18IENGINE COOLING
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM 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 en-
gine slowly or not at all. This slow cooling of the engine al-
lows the engine to warm up quickly.
The cooling system includes a radiator and recovery sub-
system, cooling fans, a thermostat and housing, a coolant
pump, and a coolant pump drive belt. 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, the intake man-
ifold, and the cylinder head. When the coolant reaches the
operating temperature of the thermostat, 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. This provides for heating and defrosting. The
surge tank is connected to the radiator to recover the cool-
ant displaced by expansion from the high temperatures.
The surge tank maintains the correct coolant level.
The cooling system for this vehicle has no radiator cap or
filler neck. The coolant is added to the cooling system
through the surge tank.
RADIATOR
This vehicle has a lightweight tube–and–fin aluminum ra-
diator. Plastic tanks are mounted on the right and the left
sides of the radiator core.
On vehicles equipped with automatic transaxles, the
transaxle fluid cooler lines run through the left radiator
tank. A radiator drain cock is on this radiator.
To drain the cooling system, open the drain cock.
SURGE TANK
The surge tank is a transparent plastic reservoir, similar to
the windshield washer reservoir.
The surge tank is connected to the radiator by a hose and
to the engine cooling system by another hose. As the ve-
hicle is driven, the engine coolant heats and expands. The
portion of the engine coolant displaced by this expansion
flows from the radiator and the engine into the surge tank.
The air trapped in the radiator and the engine is degassed
into the surge tank.When the engine stops, the engine coolant cools and con-
tracts. The displaced engine coolant is then drawn back
into the radiator and the engine. 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.
WATER PUMP
The belt–driven centrifugal water pump consists of an im-
peller, a drive shaft, and a belt pulley. The water pump is
mounted on the front of the transverse–mounted engine,
and is driven by the timing belt.
The impeller is supported by a completely sealed bearing.
The water pump is serviced as an assembly and, there-
fore, cannot be disassembled.
THERMOSTAT
A wax pellet–type thermostat controls the flow of the en-
gine coolant through the engine cooling system. The ther-
mostat is mounted in the thermostat housing to the front
of the cylinder head.
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 thermo-
stat remains closed while the engine coolant is cold, pre-
venting circulation of the engine coolant through the
radiator. At this point, the engine coolant is allowed to cir-
culate 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 en-
gine temperature operating limits.
The wax pellet in the thermostat is hermetically sealed in
a metal case. The wax element of the thermostat expands
when it is heated and contracts when it is cooled.
As the vehicle is driven and the engine warms, the engine
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 allows the engine
coolant to flow through the engine cooling 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 87°C (189°F) and is fully
open at 102°C (216°F). The thermostat closes at 86°C
(187°F).