JAC S2. Engine. Instruction — part 5

Engine Mechanical System

Engine Mechanical System 44

XIII、Cylinder cover assembly

(I)Disassemble

1. Open engine cover

2. Disconnect battery cathode cable, refer to battery cable disconnect and connect

3. Release fuel system pressure, refer to release fuel system pressure

4. Disassemble engine left front cover, refer to engine cover

5. Disassemble engine right front cover, refer to engine cover

6. Drain clutch hydraulic oil, refer to the drain and fill of clutch hydraulic oil

7. Drain transmission lubricant, refer to the drain and fill of transmission lubricant

8. Drain engine oil, refer to drain and fill of engine oil

9. Drain coolant, refer to replace coolant

10. Recycle freon, refrigerating oil, refer to freon, refrigerating oil

11. Disassemble intake hose, refer to intake hose assembly

12Disassemble pipe and expansion valve assembly, refer to pipe and expansion valve assembly

13. Disassemble water inlet and outlet assembly of warm wind, refer to disassemble water inlet and outlet assembly of warm wind

14. Disassemble air filter assembly, refer to air filter assembly

15. Disassemble battery, refer to battery

16. Disassemble battery tray, refer to battery tray

17. Disassemble back-up lamp switch, refer to back-up lamp switch

18. Disassemble clutch working cylinder, refer to clutch working cylinder and oil intake pipe assembly

19. Disassemble starter, refer to starter

20. Disassemble left front wheel, refer to wheel

21. Disassemble right front wheel, refer to wheel

22. Disassemble left driving axle assembly, refer to driving axle assembly

23. Disassemble right driving axle assembly, refer to driving axle assembly

24. Disassemble transmission assembly, refer to transmission assembly

25. Disassemble engine assembly, refer to engine assembly

26. Disassemble ignition coil, refer to ignition coil

27. Disassemble spark plug, refer to spark plug

28. Disassemble oil pressure guide rail component, refer to oil pressure guide rail component

29. Disassemble air filter bracket I, refer to air filter bracket I

30. Disassemble intake manifold, refer to intake manifold

31. Disassemble exhaust manifold, refer to exhaust manifold

32.Disassemble camshaft position sensor, refer to camshaft position sensor

33. Disassemble PCV valve, refer to PCV valve

34. Disassemble pressure regulation valve, refer to pressure regulation valve

35. Disassemble water temperature sensor, refer to water temperature sensor

36. Disassemble alternator belt, refer to alternator belt

37. Disassemble alternator, refer to alternator

38. Disassemble compression assembly, refer to compression assembly

39. Disassemble idle wheel, refer to idle wheel

40. Disassemble water pump pulley, refer to water pump pulley

41. Disassemble crankshaft pulley, refer to crankshaft pulley

42. Disassemble oil level gauge component, refer to oil level gauge component

43. Disassemble

oil sump assembly, refer to oil sump assembly

44. Disassemble cylinder cover assembly, refer to cylinder cover assembly

45. Disassemble crankshaft front oil seal, refer to crankshaft front oil seal

46. Disassemble chain wheel compartment cover, refer to chain wheel compartment cover

Engine Mechanical System

Engine Mechanical System 45

47. Disassemble timing chain, refer to timing chain

48. Disassemble camshaft, refer to camshaft

49. Disassemble engine rear lifting lug

1). Disassemble 2 fixing bolts of rear lifting lug.

2). Remove rear lifting lug

50. Disassemble alternator adjusting arm bracket

1). Disassemble

bonding bolts, Release bonding wire.

2). Disassemble 2 alternator adjusting arm brackets

3). Remove alternator adjusting arm bracket

51. Disassemble cylinder cover assembly

1). Loosen 10 bolts of cylinder cover, disassemble cylinder cover.

2). Remove cylinder cover and cylinder cover pad

52. Disassemble valve

1). Remove valve with valve spring compressor

△

Caution

Mark cylinder no. and location on disassembled

valve/ valve spring and other components, store
them well.

Engine Mechanical System

Engine Mechanical System 46

53. Disassemble valve

1). Disassemble valve lock, valve spring and valve spring retainer.

2). Disassemble valve oil seal

3). Disassemble valve retainer

4). Disassemble valve guide pipe

(II)Check

1. Check cylinder cover

1). Check if there is crack or other damage on cylinder cover.

2). Check is there is jam on water channel and oil channel of cylinder cover, please clean if yes.

3). Check the flatness of cylinder cover. Measure the flatness of

6 directions at multiple locations of cylinder bottom.

Standard value: below

0.03mm limiting value

：

0.10mm

Height of cylinder cover(new)

：(113±0.1)mm

If it is higher than standard value, please grind according to the

standard; if it is higher than limiting value, please replace

according to the specification.

△

caution

The total margin to grind of matching surface of cylinder cover and cylinder is less than 0.2mm.

2. Check valve

1). Check if the valve surface is connected correctly. If the

connection is uneven or incomplete, please repair the valve

retainer surface again.

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Engine Mechanical System

Engine Mechanical System 47

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2). Check margin thickness of valve. If it is smaller than limiting

value, please replace the valve. intake

：Standard value：1.35mm

limiting value

：0.85mm

exhaust

：Standard value：1.85mm

limiting value

：1.35mm

3). Check the total length of valve. If it is smaller than limiting value,

please replace valve.

intake

：

Standard value:89.61mm

limiting value:9.11mm

exhaust

：

Standard value: 90.94mm

limiting value: 90.44mm

3. Check valve spring

1). Check the unsupported height of valve spring. If it is higher

than limiting value, please replace valve spring.

Standard value

：43.1mm

limiting value

：42.7mm

2). Check the perpendicularity of valve spring. If it is higher than

limiting value, please replace valve spring.

Standard value

：＜ 2°

limiting value

：4°

Engine Mechanical System

Engine Mechanical System 48

(III)Installation

1. Assemble valve

1). Install valve guide pipe

2). Install valve retainer

3). Install valve oil seal

4). Install valve spring bottom seat

5). Install new valve oil seal with special tools

△

caution

Valve oil seal can’t be used repeatedly. Must use

special tools to install valve oil seal.

2. Install valve

1). Install valve with valve spring compressor.

2). Install valve spring

△

caution

Install the one with oil paint mark upwards

3). Install valve spring upper seat.

4). Install spring lock

5). To check installation, knock valve stem margin with rubber
hammer slightly after installation.

3. Install cylinder cover

1). Wipe the engine oil on cylinder cover and clean the sealant and
carbon deposit.

△

caution

Be careful not to let impurity fall into water

pump and oil pump of cylinder cover.

2). Install new cylinder pad

Engine Mechanical System

Engine Mechanical System 49

3). Smear engine oil to thread of bolts of cylinder cover and pads.

Tighten fixing bolts of cylinder cover.

Torque

(24.5±2)N·

m

4. Install engine adjusting arm bracket

1). Install engine adjusting arm bracket to cylinder cover,
tighten fixing bolts.

5. Install engine rear lifting lug

1). Install engine rear lifting lug to cylinder cover, tighten
fixing bolts.

Engine Mechanical System

Engine Mechanical System 50

6. Install camshaft

7. Install timing chain

8. Install chain wheel compartment cover

9. Install crankshaft front oil seal

10. Install cylinder cover shield component

11. Install oil sump assembly

12. Install oil level gauge component

13. Install crankshaft pulley

14. Install water pump pulley

15. Install idle wheel

16. Install compressor assembly

17. Install alternator

18. Install alternator belt

19. Install water temperature sensor

20. Install PCV valve

21. Install pressure regulating valve

22. Install camshaft position sensor

23. Install exhaust manifold

24. Install intake manifold

25. I Install air filter bracket I

26. Install spark plug

27. Install ignition coil

28. Install engine assembly

29. Install transmission assembly

30. Install right driving axle assembly

31. Install left driving axle assembly

32. Install right front wheel

33. Install left front wheel

34. Install starter

35. Install clutch working cylinder

36. Install back-up lamp switch

37. Install battery tray

38. Install battery

39. Install air filter assembly

40. Install water inlet and outlet assembly of warm wind

41. Install pipe and expansion valve assembly

42. Install intake hose

43. Fill Freon, refrigerant oil

44. Fill coolant

45. Fill engine oil

46. Fill transmission lubricant

47. Fill clutch hydraulic oil

48. Install engine right front cover shield

49. Install left front cover shield

50. Connect battery cathode cable

51. Close engine cover

Engine Mechanical System

Engine Mechanical System 50

XIV、Cylinder assembly

(I)Disassemble

1. Open engine cover

2. Disconnect battery cathode cable, refer to battery cable disconnect and connect

3. Release fuel system pressure, refer to release fuel system pressure

4. Disassemble engine left front cover, refer to engine cover

5. Disassemble engine right front cover, refer to engine cover

6. Drain clutch hydraulic oil, refer to the drain and fill of clutch hydraulic oil

7. Drain transmission lubricant, refer to the drain and fill of transmission lubricant

8. Drain engine oil, refer to drain and fill of engine oil

9. Drain coolant, refer to replace coolant

10. Recycle freon, refrigerating oil, refer to freon, refrigerating oil

11. Disassemble intake hose, refer to intake hose assembly

12. Disassemble pipe and expansion valve assembly, refer to pipe and expansion valve assembly

13. Disassemble water inlet and outlet assembly of warm wind, refer to disassemble water inlet and outlet assembly of warm wind

14. Disassemble air filter assembly, refer to air filter assembly

15. Disassemble battery, refer to battery

16. Disassemble battery tray, refer to battery tray

17. Disassemble back-up lamp switch, refer to back-up lamp switch

18. Disassemble clutch working cylinder, refer to clutch working cylinder and oil intake pipe assembly

19. Disassemble starter, refer to starter

20. Disassemble left front wheel, refer to wheel

21. Disassemble right front wheel, refer to wheel

22. Disassemble left driving axle assembly, refer to driving axle assmbly

23. Disassemble right driving axle assembly, refer to driving axle assmbly

24. Disassemble transmission assembly, refer to transmission assembly

25. Disassemble engine assembly, refer to engine assembly

26. Disassemble ignition coil, refer to ignition coil

27. Disassemble spark plug, refer to spark plug

28.

Disassemble oil pressure guide rail component, refer to oil pressure guide rail component

29. Disassemble warm wind backwater pipe, refer to warm wind backwater pipe

30. Disassemble vacuum servo steel tube, refer to vacuum servo steel tube

31.

Disassemble air filter bracket I, refer to air filter bracket I

32.

Disassemble air filter bracket

II

, refer to air filter bracket

II

33.

Disassemble intake manifold, refer to intake manifold

34.

Disassemble exhaust manifold, refer to exhaust manifold

35.

Disassemble PCV valve, refer to PCV valve

36.

Disassemble carbon tank solenoid valve, refer to carbon tank solenoid valve

37.

Disassemble electronic throttle valve, refer to electronic throttle valve

38.

Disassemble absolute pressure transducer, refer to absolute pressure transducer

39.

Disassemble water temperature sensor, refer to water temperature sensor

40.

Disassemble camshaft position sensor, refer to camshaft position sensor

41.

Disassemble crankshaft position sensor, refer to crankshaft position sensor

42.

Disassemble knocking sensor, refer to knocking sensor

43.

Disassemble

pressure regulating valve, refer to pressure regulating valve

44.

Disassemble engine oil pressure switch, refer to engine oil pressure switch

45. Disassemble alternator belt, refer to alternator belt

46. Disassemble alternator, refer to alternator

Engine Mechanical System

Engine Mechanical System 51

47. Disassemble compression assembly, refer to compression assembly

48. Disassemble idle wheel, refer to idle wheel

49. Disassemble alternator, refer to alternator

50. Disassemble compression assembly, refer to compression assembly

51. Disassemble idle wheel, refer to idle wheel

52. Disassemble water pump pulley, refer to water pump pulley

53. Disassemble crankshaft pulley, refer to crankshaft pulley

54. Disassemble oil level gauge component, refer to oil level gauge component

55. Disassemble

oil sump assembly, refer to oil sump assembly

56. Disassemble cylinder cover assembly, refer to cylinder cover assembly

57. Disassemble crankshaft front oil seal, refer to crankshaft front oil seal

58. Disassemble chain wheel compartment cover, refer to chain wheel compartment cover

59. Disassemble timing chain, refer to timing chain

60. Disassemble camshaft, refer to camshaft

61. Disassemble engine rear lifting lug, refer to engine rear lifting lug

62. Disassemble alternator adjusting arm bracket, refer to alternator adjusting arm bracket

63. Disassemble cylinder cover assembly, refer to cylinder cover assembly

64. Disassemble piston connecting rod assembly

1). Rotate crankshaft, make cylinder 2/3 at the BDC, disassemble

connecting rod bearing cap bolt of cylinder 2.

2). Hold connecting rod bolts with hand, take out connecting rod

bearing cap bolt of cylinder 2, and mark position of cylinder 2

on the bearing cap.

3). Disassemble the piston connecting rod bearing cap
of cylinder 1/3/4 respectively with the same method.

4). Push out piston connecting rod components of cylinder 1 with

wooden handle, and mark the position of cylinder 2 on the

piston and connecting rod components.

5).Disassemble the piston connecting rod assembly
of cylinder 1/3/4 respectively with the same method.

Engine Mechanical System

Engine Mechanical System 52

S2-w1043b

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65. Disassemble crankshaft

1). Rotate the rotating handle of rack, making bottom of engine face upwards.

2). Loosen and disassemble 10 main bearing cap bolts evenly according to the order in the drawing.

3). Remove main bearing cap.

4). Disassemble the main shaft bushing of main bearing cap.

5). Disassemble the thrust bearing of crankshaft on the forth main bearing seat.

△

Caution

While disassembling thrust bearing, you can rotate

crankshaft, letting them out together with thrust
bearing, which is convenient to disassemble.

6). Remove crankshaft

7). Disassemble main bearing upper tile

66. Disassemble crankshaft signal wheel

Engine Mechanical System

Engine Mechanical System 53

1). Disassemble the fixing bolts of crankshaft signal wheel

2). Remove crankshaft signal wheel

67. Disassemble piston connecting rod
component

1). Disassemble piston ring with piston
ring expander.

Piston ring expander

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2). Disassemble piston from connecting rod.

a. Insert push rod(special tool) at the mark from front, then install
guide sleeve D

b. Put the mark front of piston upwards, install piston and

connecting rod to the foundation (special tool) of piston pin.

c. Press out the piston pin with pressure machine.

d. Separate connecting rod and piston from piston and connecting
rod assembly.

△

caution After removing piston pin, put piston/piston pin and

connecting rod of the same cylinder together, please
do not mix with those from other cylinders.

3). Remove pitman box

(II)Check

1. Check crankshaft axial clearance

1). Pry crankshaft with opener, and record the readings from dial

indicator.

Standard

：0.09 ～ 0.27mm

If the measured value is out of the standard range, please replace thrust plate, and
measure again. If it’s still out of the standard range, please replace crankshaft.

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Engine Mechanical System

Engine Mechanical System 54

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2.

Check connnecting rod big end clearance

1). Measure the clearance of connnecting rod

and crank arm with feeler gauge. standard

：

0.10

～ 0.25mm

limitation

：0.4mm

If the measured value exceeds the limitation, please replace

connnecting rod and measure again. If it still exceeds the limitation,

please replace crankshaft.

3. Check the backlash of piston ring

1).

。 Measure the backlash of piston ring and piston

ring groove with feeler gauge.

standard

：

first

：0.03 ～ 0.07mm

second

： 0.02 ～ 0.06mm

limitation

：

first

：0.10mm

second

：0.10mm

If the measured value exceeds the limitation, please replace the

piston ring and measure again. If it still exceeds the limitation,

please replace the piston.

4. Check the piston ring end gap

1). Lubricate piston and piston ring with engine oil,

then insert piston ring til center of cylinder,

measure the end gap of piston ring with feeler

gauge.

standard

：

first

：0.15 ～ 0.30mm

second

：0.30 ～ 0.50mm

compound oil ring

：0.20 ～

0.50mm

limitation

：

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Engine Mechanical System

Engine Mechanical System 55

first

：0.8mm

second

：0.8mm

compound oil

ring

：1.0mm

If the measured value exceeds the limitation, please replace the

piston ring and measure again. If it still exceeds the limitation, please

replace the cylinder.

5. Check the flatness of cylinder

1). Clean the pad on surface of cylinder, and engine oil,

incrustation, carbon or other pollutants.

△

Caution

Be careful not to let Gasket sheet fall into engine

oil or engine coolant.

Measure flatness of cylinder for different directions of 6

postions with ruler and feeler gauge.

Standard value

：lower than 0.03mm

Limitating value

：lower than 0.1mm

If it exceeds the limitation, please replace cylinder.

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Engine Mechanical System

Engine Mechanical System 56

6. Check cylindricity of cylinder

1). Measure the cylinder diameter of thrust direction and axle direction
at position A and B of each cylinder with dial indicator.

Standard value

：cylinder inner diameter：75.000 ～ 75.015mm

cylindricity

：Less than 0.007mm

Replace cylinder if the average cylinder diameter of 4 positions exceeds
the maximum.

7. Check piston skirt diameter.

1). Check if piston skirt distorts with outside

micrometer

Standard value

：(74.973±0.005)mm

Replace piston if it exceeds the standard
value.

8. Check the clearance between piston and cylinder
diameter

1). Measure through piston skirt and cylinder inner
diameter.

(clearance)= (cylinder inner diameter)- (diameter of

piston skirt)

Standard value

：0.02 ～ 0.04mm

If the calculated value exceeds the limitation, please
replace piston and piston ring assembly.

9. Check the diameter of main journal of crankshaft

1). Measure the diameter of main journal of
crankshaft with outside micrometer.

standard

：46.004 ～ 46.029mm

Please replace the main shaft bushing if it exceeds
the standard.

10. Check the diameter of rod journal

1). Measure the diameter of rod journal with outside
micrometer

Standard value

：39.982 ～ 40.000mm

Please replace connecting rod bearing shell if it
exceeds the standard.

11. Check

the clearance of

rod journal

microm
eter

1). Wipe off all the engine oil on rod journal and pitman box.
2). Put plastic guage on rod journal, cut the length same with the
width of bearing bush. Plastic guage should be at the center of rod
journal, and parallel with its axis.

3). Put connecting rod cap at its position lightly, and tighten the bolts to the regulated torque.

4). Remove the bolt, remove the connecting rod cap slowly.

5). Measure the extruded part of plastic gauge at its widest point with scaleplate printed on plastic guage bag.

Standard value

：0.02 ～ 0.04mm

Limitating value

：0.10mm

6). Remove thoroughly the clearance gauge after measurement. If the clearance is bigger than limitating value, replace connecting

rod bearing shell. If necessary, replace crankshaft.

△

Caution

Measure with plastic gauge

Engine Mechanical System

Engine Mechanical System 57

12. Check the radial clearance of main axis of crankshaft

1). Wipe the engine oil on crankshaft journal and on the inner
surface of bearing bush.

2). Install bearing bush

3). Cut the length of plastic gauge, making sure it matches the width

of bearing bush. Then put it on the journal along its axial

direction

4). Install the crankshaft bearing bush cap lightly, and tighten the
bolts to regulated torque.

5). Remove the bolts, and remove crankshaft bearing bush cap
lightly.

6). Measure the extruded part of plastic gauge at its widest point with

scaleplate printed on plastic guage bag. Standard value

：

0.02

～ 0.04mm;limitating value：0.10mm

if the clearance exceeds the maximum,

，replace main bearing

bush

。If necessary, replace crankshaft.

(III)Installation

1. Install crankshaft signal wheel

1). Smear loctite 262 thread fastening sealant or similar product

onto screw of crankshaft signal wheel

2). Tighten the fixing bolts of crankshaft signal wheel

△

Caution

be sure there is no engine oil inside the thread hole of

crankshaft signal wheel while installation.

2. Fix cylinder body

1). Clean all related components.

2). Install the cylinder body to rack.

3). Rotate the rotating handle of rack, making sure the bottom of
cylinder upwards.

3. Install crankshaft

1). Blow out the engine coolant and oil out of cylinder block and

cylinder bore, clean foreign matter

△

Caution

Protect your eyes with goggle

Engine Mechanical System

Engine Mechanical System 58

S2-w1044b

S2-w1043b

2). Install the chosen crankshaft main bearing, install the main

bearing upper tile with engine oil groove onto cylinder block.

3). Drip 2-3 drops of engine lubricating oil onto each main bearing
upper tile

△

Caution

Align the embossing of bearing bush with the notch

of main bearing cap.

△

Caution

Make sure engine oil hole on the cylinder block is

in alignment with the engine oil hole of
corresponding bearing bush.

4). Install the crankshaft to cylinder block. While rotating the

crankshaft with hands, please check if the rotation is flexible.

5). Install the thrust bearing smeared with engine oil to side(forth

gear) of the main bearing with installation groove, make the

side with groove face bore hole.

6). Check crankshaft axial clearance, confirm if it conforms to the
standard of crankshaft axial clearance.

crankshaft axial clearance:0.09

～ 0.27mm

7). Drip 2-3 drops of engine oil onto crankshaft journal.

8). Install main bearing lower tile to main bearing.

9). Install main bearing cap and 10 fixing bolts

△

Caution

Recognize main bearing cap through identification

marking.

△

Caution

Install main bearing cap according to order, starting

from front(timing belt side)

△

Caution

Arrow must be towards front.

10).Rotate crankshaft 2-3 rounds, making sure engine oil is
lubricant and even.