2004 DAEWOO LACETTI water pump

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 33
DAEWOO V–121 BL4
25. Using the timing belt adjuster J–42492, rotate the
water pump until the adjust arm pointer of the tim-
ing belt automatic tensioner is aligned with the
pointer on the timing belt automatic tensioner
bracket.
26. Tighten the water pump retaining bolts.
Tighten
Tighten the water pump retaining bolts to 10 NSm (89
lb–in).
27. Remove the crankshaft pulley bolt.
28. Install the upper and lower front timing belt covers.
29. Install the upper and lower front timing belt cover
bolts.
Tighten
Tighten the front timing belt cover bolts to 10 NSm (89
lb–in).
30. Install the crankshaft pulley.
31. Install the crankshaft pulley bolt.
Tighten
Tighten the crankshaft pulley bolt to 95 NSm (70 lb–ft)
and retighten 30 degrees plus 15 degrees.
32. Install the serpentine accessory drive belt. Refer to
Section 6B, Power Steering Pump.
33. Install the right front wheel well splash shield.
34. Install the right front wheel. Refer to Section 2E,
Tires and Wheels.
35. Install the air cleaner housing.
36. Install the air cleaner housing bolts.
Tighten
Tighten the air cleaner housing bolts to 10 NSm (89 lb–
in).

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 35
DAEWOO V–121 BL4
11. Remove the upper front timing belt cover bolts.
12. Remove the upper front timing belt cover.
13. Remove the lower front timing belt cover bolts.
14. Remove the lower front timing belt cover.
15. Install the crankshaft pulley bolt.
16. Using the crankshaft pulley bolt, rotate the crank-
shaft clockwise until the timing mark on the crank-
shaft gear is aligned with the notch at the bottom of
the rear timing belt cover.
17. Slightly loosen the water pump retaining bolts.
18. Using the timing belt adjuster J–42492, rotate the
water pump counterclockwise to release the tension
on the timing belt.
19. Remove the right engine mount bracket. Refer to
”Engine Mount” in this section.
20. Remove the timing belt.

1C1 – 36I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
Installation Procedure
1. Align the timing mark on the crankshaft gear with
the notch on the bottom of the rear timing belt cov-
er.
2. Align the timing marks on the camshaft gears.
3. Install the timing belt.
4. Install the right engine mount bracket. Refer to ”En-
gine Mount” in this section.
5. Rotate the water pump clockwise using the timing
belt adjuster J–42492.
6. Rotate the water pump clockwise until the adjust
arm pointer of the timing belt automatic tensioner is
aligned with the notch in the timing belt automatic
tensioner bracket.
7. Tighten the water pump retaining bolts.
8. Rotate the crankshaft two full turns clockwise using
the crankshaft pulley bolt.
9. Loosen the water pump retaining bolts.
10. Rotate the water pump until the adjust arm pointer
of the timing belt automatic tensioner is aligned with
the pointer on the timing belt automatic tensioner
bracket.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 37
DAEWOO V–121 BL4
11. Tighten the water pump retaining bolts.
Tighten
Tighten the water pump retaining bolts to 10 NSm (89
lb–in).
12. Remove the crankshaft pulley bolt.
13. Install the upper and lower front timing belt covers.
14. Install the upper and lower front timing belt cover
bolts.
Tighten
Tighten the front timing belt cover bolts to 10 NSm (89
lb–in).
15. Install the crankshaft pulley.
16. Install the crankshaft pulley bolt.
Tighten
Tighten the crankshaft pulley bolt to 95 NSm (70 lb–ft)
and retighten 30 degrees plus 15 degrees.
17. Install the serpentine accessory drive belt. Refer to
Section 6B, Power Steering Pump.
18. Install the right front wheel well splash shield.
19. Install the right front wheel. Refer to Section 2E,
Tires and Wheels.
20. Install the air cleaner housing.
21. Install the air cleaner housing bolts.
Tighten
Tighten the air cleaner housing bolts to 10 NSm (89 lb–
in).
22. Connect the air cleaner outlet hose to the throttle
body.
23. Connect the breather tube to the camshaft cover.
24. Connect the negative battery cable.

1C1 – 66I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
4. Remove the crankshaft rear oil seal.
5. Mount the engine assembly on the engine overhaul
stand KM–412.
6. Remove the upper and the lower front timing belt
cover bolts.
7. Remove the upper and the lower front timing belt
cover.
8. Slightly loosen the water pump retaining bolts.
9. Rotate the water pump using the timing belt adjust-
er J–42492 to remove the tension from the timing
belt.
10. Remove the spark plug cover bolts.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 77
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
CYLINDER HEAD AND GASKET
The cylinder head is made of an aluminum alloy. The cylin-
der head uses cross–flow intake and exhaust ports. A
spark plug is located in the center of each combustion
chamber. The cylinder head houses the dual camshafts.
CRANKSHAFT
The crankshaft has eight integral weights which are cast
with it for balancing. Oil holes run through the center of the
crankshaft to supply oil to the connecting rods, the bear-
ings, the pistons, and the other components. The end
thrust load is taken by the thrust washers installed at the
center journal.
TIMING BELT
The timing belt coordinates the crankshaft and the dual
overhead camshafts and keeps them synchronized. The
timing belt also turns the water pump. The timing belt and
the pulleys are toothed so that there is no slippage be-
tween them. There are two idler pulleys. An automatic ten-
sioner pulley maintains the timing belt’s correct tension.
The timing belt is made of a tough reinforced rubber similar
to that used on the serpentine accessory drive belt. The
timing belt requires no lubrication.
OIL PUMP
The oil pump draws engine oil from the oil pan and feeds
it under pressure to the various parts of the engine. An oil
strainer is mounted before the inlet of the oil pump to re-
move impurities which could clog or damage the oil pump
or other engine components. When the drive gear rotates,
the driven gear rotates. This causes the space between
the gears to constantly open and narrow, pulling oil in from
the oil pan when the space opens and pumping the oil out
to the engine as it narrows.
At high engine speeds, the oil pump supplies a much high-
er amount of oil than is required for lubrication of the en-
gine. The oil pressure regulator prevents too much oil from
entering the engine lubrication passages. During normal
oil supply, a coil spring and valve keep the bypass closed,
directing all of the oil pumped to the engine. When the
amount of oil being pumped increases, the pressure be-
comes high enough to overcome the force of the spring.This opens the valve of the oil pressure regulator, allowing
the excess oil to flow through the valve and drain back to
the oil pan.
OIL PAN
The engine oil pan is mounted to the bottom of the cylinder
block. The engine oil pan houses the crankcase and is
made of cast metal.
Engine oil is pumped from the oil pan by the oil pump. After
it passes through the oil filter, it is fed through two paths
to lubricate the cylinder block and the cylinder head. In one
path, the oil is pumped through the oil passages in the
crankshaft to the connecting rods, then to the pistons and
the cylinders. It then drains back to the oil pan. In the sec-
ond path, the oil is pumped through the oil passages to the
camshaft. The oil passes through the internal passage-
ways in the camshafts to lubricate the valve assemblies
before draining back to the oil pan.
EXHAUST MANIFOLD
A single four–port, rear–takedown manifold is used with
this engine. The manifold is designed to direct escaping
exhaust gases out of the combustion chambers with a
minimum of back pressure. The oxygen sensor is
mounted to the exhaust manifold.
INTAKE MANIFOLD
The intake manifold has four independent long ports and
uses inertial supercharging to improve engine torque at
low and moderate speeds. The plenum is attached to the
intake manifold.
CAMSHAFTS
This engine is a dual overhead camshaft (DOHC) type,
which means there are two camshafts. One camshaft op-
erates the intake valves, and the other camshaft operates
the exhaust valves. The camshafts sit in journals on the
top of the engine in the cylinder head and are held in place
by camshaft caps. The camshaft journals of the cylinder
head are drilled to create oil passages. Engine oil travels
to the camshafts under pressure where it lubricates each
camshaft journal. The oil returns to the oil pan through
drain holes in the cylinder head. The camshaft lobes are
machined into the solid camshaft to open and close the in-
take and the exhaust valves precisely the correct amount
at the correct time. The camshaft lobes are oiled by splash
action from pressurized oil escaping from the camshaft
journals.

1.8L DOHC ENGINE MECHANICAL 1C2 – 11
DAEWOO V–121 BL4
1. Connecting Rod
2. Bearing Set
3. Connecting Rod Bolt
4. Piston Ring Set
5. Piston Pin
6. Piston
7. Engine Block
8. Sleeve
9. Water Jacket Cap
10. Bolt (Manual Transaxle)
11. Flywheel (Manual Transaxle)
12. Flexible Plate (Automatic Transaxle)
13. Bolt (Automatic Transaxle)
14. Clamp
15. Hose
16. Clamp
17. Engine Ventilation Pipe
18. Bolt
19. Gasket
20. Needle Sleeve
21. Crankshaft Rear Seal
22. Crankshaft
23. Transmitter Disk
24. Bolt
25. Oil Pan Scraper
26. Oil Pan
27. Drain Plug
28. Washer
29. Bolt
30. Sleeve
31. Gasket
32. Bolt
33. Oil Pump Cover
34. Ring Gear
35. Gear
36. Oil Pressure Switch
37. Washer
38. Washer
39. Oil Duct Outlet Plug
40. Connecting Piece
41. Seal Ring
42. Oil Filter43. Bypass Valve
44. Pressure Relief Valve Plunger
45. Pressure Relief Valve Spring
46. Seal Ring
47. Pressure Relief Valve Plug
48. Seal Ring
49. Bolt
50. Oil Suction Pipe
51. Bolt
52. Rear Timing Belt Cover
53. Bolt
54. Special Bolt
55. Idler Pulley
56. Stud
57. Nut
58. Bolt
59. Tensioner
60. Bolt
61. Thrust Inner Washer
62. Woodruff Key
63. Crankshaft Gear
64. Thrust Outer Washer
65. Bolt
66. Camshaft Drive Belt
67. Gasket
68. Front Timing Belt Cover
69. Bolt
70. Bushing Plug
71. Bushing
72. Oil Gallery Plug
73. Bolt
74. Water Pump
75. Seal Ring
76. Crankshaft Position Sensor
77. Bolt
78. Knock Sensor*
79. Bolt
80. Bolt
81. Crankshaft Bearing Bridge
* : 2.0L DOHC Engine

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. . . . . . . . . . . . . . . . . . . . . .