2004 DAEWOO LACETTI Gear

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.

1C1 – 42I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
7. Clean the oil pump housing and all the oil pump
parts.
8. Inspect all the oil pump parts for signs of wear. Re-
fer to ”Engine Specifications” in this section. Re-
place the worn oil pump parts.
Notice : Pack the oil pump gear cavity with petroleum jelly
to ensure an oil pump prime, or engine damage could re-
sult.
9. Coat all the oil pump parts with clean engine oil.
Install the oil pump parts.
10. Apply Loctite® 242 to the oil pump rear cover bolts
and install the cover and bolts.
Tighten
Tighten the oil pump rear cover bolts to 8 NSm (71 lb–
in).
11. Install the safety relief valve, spring, washer and
bolt.
Tighten
Tighten the safety relief valve bolt to 30 NSm (22 lb–ft).
Installation Procedure
1. Apply Loctite® 242 to the oil pump bolts and room
temperature vulcanizing (RTV) sealant to the new
oil pump gasket.
2. Install the gasket to the oil pump and install the oil
pump to the engine block with the bolts.
Tighten
Tighten the oil pump bolts to 10 NSm (89 lb–in).
3. Install a new oil pump–to–crankshaft seal. Coat the
lip of the seal with a thin coat of grease.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 45
DAEWOO V–121 BL4
CAMSHAFT GEARS
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the engine cover.
3. Remove the timing belt. Refer to ”Timing Belt” in
this section.
4. Disconnect the ignition wires from the spark plugs.
5. Disconnect the engine ventilation hoses from the
camshaft cover.
6. Remove the camshaft cover bolts.
7. Remove the camshaft cover and the camshaft cov-
er gasket.
Notice : Take extreme care to prevent any scratches,
nicks or damage to the camshafts.
8. While holding the intake camshaft firmly in place,
remove the intake camshaft gear bolt.
9. Remove the intake camshaft gear.
10. While holding the exhaust camshaft firmly in place,
remove the exhaust camshaft gear bolt.
11. Remove the exhaust camshaft gear.
Installation Procedure
Notice : Take extreme care to prevent any scratches,
nicks or damage to the camshafts.
1. Install the intake camshaft gear.
2. While holding the intake camshaft firmly in place,
install the intake camshaft gear bolt.
Tighten
Tighten the intake camshaft gear bolt to 67.5 NSm (49
lb–ft).

1C1 – 46I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
3. Install the exhaust camshaft gear.
4. While holding the exhaust camshaft firmly in place,
install the exhaust camshaft gear bolt.
Tighten
Tighten the exhaust camshaft gear bolt to 67.5 NSm
(49 lb–ft).
5. Apply a small amount of gasket sealant to the cor-
ners of the front camshaft caps and to the top of
the rear camshaft cover–to–cylinder head seal.
6. Install the camshaft cover and the camshaft cover
gasket.
7. Install the camshaft cover bolts.
Tighten
Tighten the camshaft cover nuts to 10 NSm (89 lb–in).
8. Connect the engine ventilation hoses to the cam-
shaft cover.
9. Connect the ignition wires to the spark plugs.
10. Install the timing belt. Refer to ”Timing Belt” in this
section.
11. Install the engine cover. Refer to ”Engine Cover” in
this section.
12. Connect the negative battery cable.
REAR TIMING BELT COVER
Removal Procedure
1. Remove the timing belt and the timing belt cover.
Refer to ”Timing Belt” in this section.
2. Remove the camshaft gears. Refer to ”Camshaft
Gears” in this section.
3. Remove the crankshaft gear.
4. Remove the timing belt automatic tensioner bolts.
5. Remove the timing belt automatic tensioner.

1C1 – 48I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
5. Install the timing belt automatic tensioner.
6. Install the timing belt automatic tensioner bolts.
Tighten
Tighten the timing belt automatic tensioner bolts to 25
NSm (18 lb–ft).
7. Install the crankshaft gear.
Notice : Take extreme care to prevent any scratches,
nicks or damage to the camshafts.
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.
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. Remove the air cleaner outlet hose from the throttle
body and air cleaner housing.
7. Disconnect the breather tubes from the camshaft
cover.
8. Remove the serpentine accessory drive belt. Refer
to Section 6B, Power Steering Pump.
9. Remove the right front wheel. Refer to Section 2E,
Tires and Wheels.
10. Remove the right front wheel well splash shield.
11. Drain the engine coolant. Refer to Section 1D, En-
gine Cooling.
12. Remove the cooling system radiator and the engine
cooling fans. Refer to Section 1D, Engine Cooling.
13. Disconnect the upper radiator hose from the ther-
mostat housing.
14. Disconnect the power steering return hose from the
power steering pump. Refer to Section 6A, Power
Steering System.
15. Disconnect the power steering pressure hose from
the power steering pump. Refer to Section 6A,
Power Steering System.
16. Disconnect the electrical connector at the direct
ignition system (DIS) coil and the electronic control
module (ECM) ground terminal at the intake man-
ifold and at the starter motor.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 67
DAEWOO V–121 BL4
11. Disconnect the engine ventilation hoses from the
camshaft cover.
12. Disconnect the oil filler cap.
13. Remove the spark plug cover bolts.
14. Remove the spark plug cover.
15. Disconnect the ignition wires from the spark plugs.
16. Remove the camshaft cover nuts.
17. Remove the camshaft cover washers.
18. Remove the camshaft cover and the camshaft cov-
er gasket.
Notice : Take extreme care to prevent any scratches,
nicks or damage to the camshafts.
19. While holding the intake camshaft firmly in place,
remove the intake camshaft bolt.
20. Remove the intake camshaft gear.
21. While holding the exhaust camshaft firmly in place,
remove the exhaust camshaft bolt.
22. Remove the exhaust camshaft gear.
23. Remove the timing belt automatic tensioner bolts.
24. Remove the timing belt automatic tensioner.
25. Remove the timing belt idler pulley bolt.
26. Remove the timing belt idler pulley.
27. Remove the crankshaft timing belt gear.
28. Remove the rear timing belt cover bolts.
29. Remove the rear timing belt cover.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 73
DAEWOO V–121 BL4
36. Install the crankshaft timing belt gear.
37. Install the timing belt automatic tensioner.
38. Install the timing belt automatic tensioner bolts.
Tighten
Tighten the timing belt automatic tensioner bolts to 25
NSm (18 lb–ft).
39. Install the timing belt idler pulley.
40. Install the timing belt idler pulley bolt.
Tighten
Tighten the timing belt idler pulley bolt to 40 NSm (30
lb–ft).
Notice : Take extreme care to prevent any scratches,
nicks or damage to the camshafts.
41. Install the intake camshaft gear.
42. Install the intake camshaft gear bolt while holding
the intake camshaft firmly in place.
Tighten
Tighten the intake camshaft gear bolt to 67.5 NSm (49
lb–ft).
43. Install the exhaust camshaft gear.
44. Install the exhaust camshaft gear bolt while holding
the exhaust camshaft firmly in place.
Tighten
Tighten the exhaust camshaft gear bolt to 67.5 NSm
(49 lb–ft).
45. Install the timing belt. Refer to ”Timing Belt” in this
section.
46. Adjust the timing belt tension. Refer to ”Timing Belt
Check and Adjust” in this section.
47. Apply a small amount of gasket sealant to the cor-
ners of the front camshaft caps and to the top of
the rear camshaft cover–to–cylinder head seal.
48. Install the camshaft cover and the camshaft cover
gasket.
49. Install the camshaft cover washers.
50. Install the camshaft cover nuts.
Tighten
Tighten the camshaft cover nuts to 10 NSm (89 lb–in).
51. Connect the ignition wires to the spark plugs.
52. Connect the oil filler cap.
53. Connect the engine ventilation hose to the cam-
shaft cover.
54. Install the upper and the lower front timing belt cov-
ers.
55. Install the upper and the lower front timing belt cov-
er bolts.
Tighten
Tighten the upper and the lower front timing belt cover
bolts to 10 NSm (89 lb–in).

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.