Packet No.

Thickness (mm/in)

Packet No.

Thickness (mm/in)

10

5.10 (0.2008)

46

5.46 (0.2150)

12

5.12 (0.2016)

48

5.48 (0.2157)

14

5.14 (0.2024)

50

5.50 (0.2165)

16

5.16 (0.2031)

52

5.52 (0.2173)

18

5.18 (0.2039)

54

5.54 (0.2181)

20

5.20 (0.2047)

56

5.56 (0.2189)

22

5.22 (0.2055)

58

5.58 (0.2197)

24

5.24 (0.2063)

60

5.60 (0.2205)

26

5.26 (0.2071)

62

5.62 (0.2213)

28

5.28 (0.2079)

64

5.64 (0.2220)

30

5.30(0.2087)

66

5.66(0.2236)

32

5.32(0.2094)

68

5.68(0.2236)

34

5.34(0.2102)

70

5.70(0.2252)

36

5.36(0.2110)

72

5.72(0.2260)

38

5.38(0.2118)

74

5.74(0.2260)

40

5.40(0.2126)

 

 

Engine

Engine Mechanical System JL4G18-D

2-303

2.6.1.4  Intake  and  Exhaust  Valves  Lifter
Selection Table

Intake Valve Selection Table

Lifter No. and 
Thickness

Gap

2-304

Engine Mechanical System JL4G18-D

Engine

Exhaust Valve Selection Table

Lifter No. and 
Thickness

Gap

Engine

Engine Mechanical System JL4G18-D

2-305

2.6.2 Description and Operation
2.6.2.1 Description and Operation

1. Cylinder Head

Cylinder head is made from aluminum alloy casting process.
cylinder valve stem is a mechanical system. valve clearance
can not be automatically adjust, which is very important. The
cylinder valve is an integrated part. OEMs can offer 38 different
sizes  to  choose  from.  During  the  repair,  required  quite  tube
thickness  can  be  calculated  according  to  the  formula.  For
specific  information.  Refer  to 

2.6.8.20

 

Valve  Clearance

Adjustments

.  With  Double  overhead  camshaft  layout,  in  the

drive  sprocket  on  the  intake  camshaft  there  is  also  a  VVT
actuator for adjusting the intake valve timing. For the detailed
working principle. Refer to 

2.6.3.1

 

System Working Principle

.

2. Timing Chain

Dual overhead camshafts are driven by a timing chain. Timing
chain must be replaced every 120,000 kilometers. Timing chain
system consists of timing chain, timing chain guide rails, timing
chain  tensioner  rail  and  the  timing  chain  tensioner.  Timing
chain tensioner tensioning is provide by the pressure from the
oil  pump  to  ensure  the  timing  chain  tensioner  maintain  a
constant intensity. Timing chain lubrication is provided by the
oil pump nozzles. Refer to 

2.6.8.11

 

Timing Chain Inspection

for

specific information.

3. Intake Manifold

Intake manifold has four independent long ports, using inertia
to improve the engine torque at low speed.

4. Camshaft

Dual  overhead  camshaft  (DOHC)  has  two  camshafts.  A
camshaft  controls  the  intake  valves,  the  other  camshaft
controls  the  exhaust  valves.  The  camshaft  is  located  in  the
journal in the cylinder head on the top of the engine and fixed
with  camshaft  cover.  The  cylinder  head  camshaft  journal
drilling is used for engine oil channel. Engine oil flows to the
camshaft  under  pressure,  lubrication  each  camshaft  journal.
Engine oil flows through the cylinder lid to return to oil sump.
Cam convex corner is formed by machining, at the right time,
according  to  the  appropriate  amount,  accurately  open  and
close intake and exhaust valves. Cam convex is lubricated by
high-pressure oil escaped from the engine camshaft.

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Engine Mechanical System JL4G18-D

Engine