2004 DAEWOO LACETTI cooling

1C2 – 46I1.8L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
7. Install the timing belt automatic tensioner and bolt.
8. Install the camshaft gears. Refer to ”Camshaft
Gears” in this section.
9. Install the timing belt and timing belt cover. Refer to
”Timing Belt” in this section.
10. Connect the negative battery cable.
ENGINE
Removal Procedure
1. Remove the fuel pump fuse.
2. Start the engine. After it stalls, crank the engine for
10 seconds to rid the fuel system of fuel pressure.
3. Remove the hood. Refer to Section 9R, Body Front
End.
4. Drain the engine oil.
5. Disconnect the negative battery cable.
6. Discharge the air conditioning (A/C) system, if
equipped. Refer to Section 7B, Manual Control
Heating, Ventilation, and Air Conditioning Systems.
7. Disconnect the manifold air temperature (MAT)
sensor connector.
8. Remove the air cleaner outlet hose from the throttle
body and air cleaner housing.
9. Disconnect the breather tubes from the camshaft
cover.
10. Remove the right front wheel. Refer to Section 2E,
Tires and Wheels.
11. Remove the right front wheel well splash shield.
Refer to Section 9R, Body Font End.
12. Remove the serpentine accessory drive belt. Refer
to Section 6B, Power Steering Pump.
13. Drain the engine coolant. Refer to Section 1D, En-
gine Cooling.
14. Remove the cooling system radiator and the engine
cooling fans. Refer to Section 1D, Engine Cooling.
15. Disconnect the upper radiator hose from the ther-
mostat housing.
16. Disconnect the power steering return hose from the
power steering pump.
17. Disconnect the power steering pressure hose from
the power steering pump.
18. Disconnect the electrical connector at the direct
ignition system (DIS) coil and the electronic control
module (ECM) ground terminal and at the starter
motor.

1C2 – 50I1.8L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
18. Install the exhaust flex pipe retaining nuts to the
catalytic converter or the connecting pipe.
Tighten
Tighten the exhaust flex pipe–to–catalytic converter
or connecting pipe retaining nuts to 35 NSm (26 lb–ft).
19. Connect the power steering pressure hose.
20. Connect the power steering return hose.
21. Install the A/C compressor, if equipped. Refer to
Section 7B, Manual Control Heating, Ventilation,
and Air Conditioning System.
22. Install the serpentine accessory drive belt. Refer to
Section 6B, Power Steering Pump.
23. Install the right front wheel well splash shield.
24. Install the right front wheel. Refer to Section 2E,
Tires and Wheels.
25. Connect the fuel feed line to the fuel rail.
26. Connect the fuel return line to fuel rail.
27. Install the fuel rail and injector channel cover as an
assembly. Refer to Section 1F, Engine Controls.
28. Connect all of the necessary vacuum lines including
the brake booster vacuum hose.
29. Connect the O2 sensor connector, if equipped.
30. Connect the starter solenoid ”S” terminal wire and
power lead.
31. Connect the generator voltage regulator connector.
32. Connect the CTS connector.
33. Connect the engine CTS connector.
34. Connect the TPS connector.
35. Connect the IAC valve connector.
36. Connect the MAP sensor connector.
37. Connect the knock sensor, if necessary
38. Connect the electrical connector at the DIS ignition
coil and the ECM ground terminal and at the starter
motor.
39. Install the air cleaner outlet hose between the
throttle body and the air cleaner housing.
40. Connect the breather tubes to the camshaft cover.
41. Connect the MAT sensor connector.
42. Install the cooling system radiator and the engine
cooling fans. Refer to Section 1D, Engine Cooling.

1.8L DOHC ENGINE MECHANICAL 1C2 – 51
DAEWOO V–121 BL4
43. Connect the lower radiator hose to the coolant pipe.
44. Connect the upper radiator hose to the thermostat
housing.
45. Connect the heater inlet hose to the cylinder head.
46. Connect the heater outlet hose to the coolant pipe.
47. Connect the coolant surge tank hose to the coolant
pipe.
48. Connect the coolant hose to the throttle body.
49. Connect the throttle cable to the throttle body and
the intake manifold bracket.
50. Install the fuel pump fuse.
51. Connect the negative battery cable.
52. Refill the engine crankcase with engine oil.
53. Refill the engine coolant system. Refer to Section
1D, Engine Cooling.
54. Bleed the power steering system. Refer to Section
6A, Power Steering.
55. Refill the A/C refrigerant system, if equipped. Refer
to Section 7B, Manual Control Heating, Ventilation,
and Air Conditioning System.
56. Install the hood. Refer to Section 9R, Body Front
End.
PISTONS AND RODS
Tools Required
J–8037 Universal Piston Ring Compressor
J–8087 Cylinder Bore Check Gauge
KM–427 Piston Pin Service Set
KM–470–B Angular Torque Gauge
Removal Procedure
1. Remove the cylinder head with the intake manifold
and exhaust manifold attached. Refer to ”Cylinder
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 and support
bracket bolts.
4. Remove the oil suction pipe.
5. Remove the crankshaft bearing bridge and the oil
pan scraper bolts.
6. Remove the crankshaft bearing bridge and the oil
pan scraper.

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

ENGINE COOLING 1D – 3
DAEWOO V–121 BL4
DIAGNOSIS
THERMOSTAT TEST
1. Remove the thermostat from the vehicle. Refer to
”Thermostat” in this section.
2. Make sure the valve spring is tight when the ther-
mostat is fully closed. If the spring is not tight, re-
place the thermostat.
3. Suspend the thermostat and a thermometer in a
pan of 50/50 mixture of ethylene glycol and water.
Do not let the thermostat or the thermometer rest
on the bottom of the pan because the uneven con-
centration of heat on the bottom could result in in-
accurate temperature 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 87°C
(189°F) and it should be fully open at 102°C
(216°F). If it does not open at these temperatures,
replace the thermostat.
SURGE TANK CAP TEST
Tools Required
KM–471 Adapter
The surge tank cap maintains proper pressure, protects
the system from high pressure by opening a pressure
valve, and protects the coolant hoses from collapsing be-
cause 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 dam-
age or deformity is found, replace the cap.
3. Install a suitable cooling system pressure tester to
the cap using the adapter KM–471.
4. Pull the vacuum pressure valve open. If the surge
tank cap does not seal properly, replace the surge
tank cap.
5. Pressurize the cap to 90 to 120 kPa (13.1 to 17.4
psi).
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 80 kPa (11.6 psi), replace the
surge tank cap.

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.

ENGINE COOLING 1D – 5
DAEWOO V–121 BL4
COMPONENT LOCATOR
RADIATOR/FAN
1. Holder Transmission Fluid Pipe (Automatic Trans-
mission Only)
2. Upper Radiator Bumper
3. Front Upper Center Panel
4. Radiator
5. Lower Radiator Bumper6. Spring Clamp
7. Upper Radiator Hose
8. Main Cooling Fan
9. Auxiliary Cooling Fan
10. Drain Cock