Section 5 DAEWOO LACETTI 2004 Service Repair Manual

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.

ENGINE COOLING 1D – 11
DAEWOO V–121 BL4
Installation Procedure
1. Install the thermostat into the thermostat housing
by pressing the thermostat mounting flange down-
ward and then rotating the flange counterclockwise.
Rotate the thermostat mounting flange until it is
seated in the thermostat housing recesses.
2. Coat the sealing surface of a new seal ring with
Lubriplater®.
3. Install a new seal ring into the recess in the thermo-
stat housing.
4. Install the thermostat housing to the cylinder head.
5. Secure the thermostat housing to the cylinder head
with the mounting bolts.
Tighten
Tighten the thermostat housing mounting bolts to 15
NSm (11 lb–ft).
6. Connect the upper radiator hose to the thermostat
housing.
7. Secure the upper radiator hose to the thermostat
housing with a hose clamp.
8. Refill the engine cooling system. Refer to ”Draining
and Refilling the Cooling System” in this section.
WATER PUMP
Removal Procedure
1. Drain the engine cooling system to a level below
the thermostat housing. Refer to ”Draining and Re-
filling the Cooling System” in this section.
2. Remove the timing belt. Refer to Section 1C DOHC
Engine Mechanical.
3. Remove the timing belt tension roller retaining bolt.
4. Remove the timing belt tension roller.

1D – 12IENGINE COOLING
DAEWOO V–121 BL4
5. Remove the water pump mounting bolts.
6. Remove the water pump from the engine block.
7. Remove the ring seal from the water pump.
Inspection Cleaning Procedure
1. Inspect the water pump body for cracks and leaks.
2. Inspect the water pump bearing for play or abnor-
mal noise.
3. Inspect the water pump pulley for excessive wear.
If the water pump is defective, replace the water
pump as a unit.
4. Clean the mating surfaces of the water pump and
the engine block.
Installation Procedure
1. Install a new ring seal to the water pump.
2. Coat the sealing surface of the ring seal with Lubri-
plater®.
3. Install the water pump to the engine block with the
flange aligned with the recess of the rear timing belt
cover.
4. Secure the water pump to the engine block with the
mounting bolts.
Tighten
Tighten the water pump mounting bolts to 25 NSSm
(18 lb–ft).
5. Install the timing belt tension roller to the oil pump
with the flange inserted into the recess of the oil
pump.
6. Install the timing belt tension roller bolt. Do not
tighten the bolt at this time.
7. Install the timing belt. Refer to Section 1C, DOHC
Engine Mechanical.
8. Refill the engine cooling system. Refer to ”Draining
and Refilling the Cooling System” in this section.

1D – 16IENGINE COOLING
DAEWOO V–121 BL4
RADIATOR
Removal Procedure
1. Disconnect the negative battery cable.
2. Drain the engine cooling system. Refer to ”Draining
and Refilling the Cooling System” in this section.
3. Remove the main and the auxiliary cooling fans.
Refer to ”Electric Cooling Fan – Main or Auxiliary”
in this section.
4. Remove the upper radiator retaining bolt.
5. Remove the upper radiator retaining bracket.
6. Remove the upper radiator hose clamp.
7. Disconnect the upper radiator hose from the radia-
tor.
8. Remove the hose clamp from the surge tank hose
at the radiator.
9. Disconnect the surge tank hose from the radiator.
10. Remove the lower radiator hose clamp.
11. Disconnect the lower radiator hose from the radia-
tor.
12. Disconnect the transaxle cooler pipes from the low-
er radiator tank, if equipped.
13. Remove the bolt and the transaxle pipe support
clamp from the radiator.
14. Remove the radiator from the vehicle.
Important : The radiator still contains a substantial
amount of coolant. Drain the remainder of the coolant from
the radiator into a drain pan.
Installation Procedure
1. Set the radiator into place in the vehicle with the
radiator bottom posts in the rubber shock bumpers.
2. Connect the transaxle cooler pipes to the lower ra-
diator tank, if equipped.
3. Install the transaxle pipe and support clamp to the
radiator with a bolt.
4. Connect the surge tank hose to the radiator.
5. Secure the surge tank hose with a hose clamp.
6. Connect the upper radiator hose and the lower ra-
diator hose to the radiator.
7. Secure each hose with a hose clamp.
8. Position the radiator retainers in place.
9. Install the upper radiator retainer bracket.
10. Install the upper radiator retaining bolt.

ENGINE COOLING 1D – 17
DAEWOO V–121 BL4
11. Install the main and the auxiliary cooling fans. Refer
to ”Electric Cooling Fan – Main or Auxiliary” in this
section.
12. Refill the engine cooling system. Refer to ”Draining
and Refilling the Cooling System” in this section.
13. Connect the negative battery cable.
Tighten
Tighten the radiator retaining bolt to 8 NSm (71 lb–in).

SECTION : 1E
ENGINE ELECTRICAL
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
SPECIFICATIONS1E–2 . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter Specifications 1E–2. . . . . . . . . . . . . . . . . . . . . .
Battery Specifications 1E–2. . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 1E–3. . . . . . . . . .
SCHEMATIC AND ROUTING DIAGRAMS1E–4 . . . . .
Startimg System 1E–4. . . . . . . . . . . . . . . . . . . . . . . . . .
Charging System 1E–5. . . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSIS1E–6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
No Crank 1E–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter Motor Noise 1E–9. . . . . . . . . . . . . . . . . . . . . . .
Battery Load Test 1E–9. . . . . . . . . . . . . . . . . . . . . . . . .
Genrator Output Test 1E–10. . . . . . . . . . . . . . . . . . . . .
Generator System Check 1E–10. . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR1E–11 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 1E–11. . . . . . . . . . . . . . . . . . . .
Generator 1E–11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter 1E–14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery and Battery Tray 1E–15. . . . . . . . . . . . . . . . . . . UNIT REPAIR 1E–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starter Motor 1E–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Generator 1E–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION1E–30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery 1E–30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ratings 1E–30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reserve Capacity 1E–30. . . . . . . . . . . . . . . . . . . . . . . . .
Cold Cranking Amperage 1E–30. . . . . . . . . . . . . . . . . .
Built–In Hydrometer 1E–30. . . . . . . . . . . . . . . . . . . . . . .
Charging Procedure 1E–30. . . . . . . . . . . . . . . . . . . . . . .
Charging Time Required 1E–31. . . . . . . . . . . . . . . . . . .
Charging a Completely Discharged Battery
(OFF the Vehicle) 1E–31. . . . . . . . . . . . . . . . . . . . . . .
Jump Starting Procedure 1E–31. . . . . . . . . . . . . . . . . .
Generator 1E–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Charging System 1E–32. . . . . . . . . . . . . . . . . . . . . . . . .
Starter 1E–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starting System 1E–32. . . . . . . . . . . . . . . . . . . . . . . . . .

ENGINE ELECTRICAL 1E – 9
DAEWOO V–121 BL4
STARTER MOTOR NOISE
To correct starter motor noise during starting, use the following procedure:
Checks
Action
Check for a high–pitched whine during cranking, before
the engine fires. The engine cranks and fires properly.The distance is too great between the starter pinion and
the flywheel. Shimming the starter toward the flywheel is
required.
Check for a high–pitched whine after the engine fires, as
the key is being released. The engine cranks and fires
properly. This intermittent complaint is often diagnosed as
”starter hang–in” or ”solenoid weak.”The distance is too small between the starter pinion and
the flywheel. Shimming the starter away from the flywheel
is required.
Check for a loud ”whoop” after the engine fires but while
the starter is still held engaged. The sound is like a siren
if the engine is revved while the starter is engaged.The most probable cause is a defective clutch. A new
clutch will often correct this problem.
Check for a ”rumble,” a ”growl,” or, in severe cases, a
”knock” as the starter is coasting down to a stop after start-
ing the engine.The most probable cause is a bent or unbalanced starter
armature. A new armature will often correct this problem.
If the complaint is noise, correction can be achieved by
proper shimming as follows:
1. Check for a bent or a worn flywheel.
2. Start the engine and carefully touch the outside di-
ameter of the rotating flywheel ring gear with chalk
or a crayon to show the high point of the tooth run-
out. Turn the engine OFF and rotate the flywheel so
that the marked teeth are in the area of the starter
pinion gear.
3. Disconnect the negative battery cable to prevent
cranking the engine.
4. Check the pinion–to–flywheel clearance by using a
wire gauge of 0.5 mm (0.02 inch) minimum thick-
ness (or diameter). Center a pinion tooth between
two flywheel teeth and the gauge. Do not gauge in
the corners, where a misleading larger dimension
may be observed. If the clearance is under this
minimum, shimming the starter away from the fly-
wheel is required.
5. If the clearance approaches 1.5 mm (0.06 inch) or
more, shimming the starter toward the flywheel is
required. This condition is generally the cause of
broken flywheel teeth or the starter housing. Shim
the starter toward the flywheel by shimming only
the outboard starter mounting pad. A shim of 0.40
mm (0.016 inch) thickness at this location will de-
crease the clearance by approximately 0.30 mm
(0.012 inch). If normal starter shims are not avail-
able, plain washers or other suitable material may
be used as shims.BATTERY LOAD TEST
1. Check the battery for obvious damage, such as a
cracked or broken case or cover, which could per-
mit the loss of electrolyte. If obvious damage is
noted, replace the battery.
CAUTION : Do not charge the battery if the hydrome-
ter is clear or light yellow. Instead, replace the battery.
If the battery feels hot, or if violent gassing or spew-
ing of electrolyte through the vent hole occurs, dis-
continue charging or reduce the charging rate to
avoid personal injury.
2. Check the hydrometer. If the green dot is visible, go
to the load test procedure. If the indicator is dark
but green is not visible, charge the battery. For
charging a battery removed from the vehicle, refer
to ”Charging a Completely Discharged Battery” in
this section.
3. Connect a voltmeter and a battery load tester
across the battery terminals.
4. Apply a 300–ampere load for 15 seconds to remove
any surface charge from the battery.
5. Remove the load.
6. Wait 15 seconds to let the battery recover, and ap-
ply a 270–ampere load.
Important : The battery temperature must be estimated
by touch and by the temperature condition the battery has
been exposed for the preceding few hours.
7. If the voltage does not drop below the minimum
listed, the battery is good and should be reinstalled.
If the voltage is less than the minimum listed, re-
place the battery. Refer to ”Battery Specifications”
in this section.

1E – 10IENGINE ELECTRICAL
DAEWOO V–121 BL4
GENRATOR OUTPUT TEST
1. Perform the generator system test. Refer to ”Gen-
erator System Check”in this section.
2. Replace the generator if it fails that test. Refer to
”Generator” in the On–Vehicle Service portion of
this section. If it passes the test, perform the on–
vehicle output check which follows.
Important : Always check the generator for output before
assuming that a grounded ”L” terminal circuit has dam-
aged the regulator.
3. Attach a digital multimeter, an ammeter, and a car-
bon pile load to the vehicle.
Important : Be sure the vehicle battery is fully charged,
and the carbon pile load is turned off.
4. With the ignition switch in the OFF position, check
and record the battery voltage.
5. Remove the harness connector from the generator.
6. Turn the ignition to RUN with the engine not run-
ning. Use a digital multimeter to check for voltage in
the harness connector ”L” terminal.
7. The reading should be near the specified battery
voltage of 12 volts. If the voltage is too low, check
the indicator
L" terminal circuits for open and
grounded circuits causing voltage loss. Correct any
open wires, terminal connections, etc., as neces-
sary. Refer to”Charging System” in this section.
8. Attach the generator harness connector.
9. Run the engine at a moderate idle, and measure
the voltage across the battery terminals. The read-
ing should be above that recorded in step 14, but
less than 16 volts. If the reading is over 16 volts or
below the previous reading, replace the generator.
Refer to”Generator” in the On–Vehicle Service sec-
tion.
10. Run the engine at a moderate idle, and measure
the generator amperage output.
11. Turn on the carbon pile, and adjust it to obtain the
maximum amps while maintaining the battery volt-
age above 13 volts.
12. If the reading is within 15 amps of the generator’s
rating noted on the generator, the generator is
good. If not, replace the generator. Refer to”Gener-
ator” in the On–Vehicle Service section.
13. With the generator operating at the maximum out-
put, measure the voltage between the generator
housing and the battery negative terminal. The volt-
age drop should be 0.5 volt or less. If the voltage
drop is more than 0.5 volt, check the ground path
from the generator housing to the negative battery
cable.
14. Check, clean, tighten, and recheck all of the ground
connections.
GENERATOR SYSTEM CHECK
When operating normally, the generator indicator lamp will
come on when the ignition is in RUN position and go out
when the engine starts. If the lamp operates abnormally
or if an undercharged or overcharged battery condition oc-
curs, the following procedure may be used to diagnose the
charging system. Remember that an undercharged bat-
tery is often caused by accessories being left on overnight
or by a defective switch that allows a lamp, such as a trunk
or a glove box lamp, to stay on.
Diagnose the generator with the following procedure:
1. Visually check the belt and the wiring.
2. With the ignition in the ON position and the engine
stopped, the charge indicator lamp should be on. If
not, detach the harness at the generator and
ground the ”L” terminal in the harness with a 5–am-
pere jumper lead.
S If the lamp lights, replace the generator. Refer to
”Generator” in the On–Vehicle Service section.
S If the lamp does not light, locate the open circuit
between the ignition switch and the harness
connector. The indicator lamp bulb may be
burned out.
3. With the ignition switch in the ON position and the
engine running at moderate speed, the charge indi-
cator lamp should be off. If not, detach the wiring
harness at the generator.
S If the lamp goes off, replace the generator. Re-
fer to ”Generator” in the On–Vehicle Service
section.
S If the lamp stays on, check for a short to ground
in the harness between the connector and the
indicator lamp.
Important : Always check the generator for output before
assuming that a grounded ”L” terminal circuit has dam-
aged the regulator. Refer to”Generator” in the Unit Repair
section.