Great Wall engine 4G64S4M. Manual — part 10

11-34

ENGINE

CYLINDER HEAD AND VALVE

Valve Spring

(1)

Measure the free spring height, in case it is less than the limit

value, change the spring.

Standard value: 51.0 mm

Limit value: 50.0 mm

(2)

Measure the perpendicularity of the center line with the surface

of the spring, if the gradient exceeds the limit, change the spring.

Standard value:

2

Limit value: 4

Valve Guide

(1)

Measure the clearance between the valve guide and the valve

stern, if the clearance exceeds the limit value, Change the valve

guide or valve or both of them.

Standard value:

Intake value . . . . . . ... 0.02

0.05mm

Exhaust value . . . . . . 0.03

0.07mm

Limit value:

Intake value . . . . . . ... 0.10mm

Exhaust value . . . . . . 0.15mm

Valve Seat

1) Assemble the valve and measure the protruding height of the

valve stern between the end of valve stern and valve spring seat.

In case the measured value exceeds the specified limit, change

the valve seat.

Standard value:

Intake value . . . . . . ... 49.30mm

Exhaust valve . . . . . . 49.30mm

Limit value:

Intake value . . . . . . ... 49.80mm

Exhaust value . . . . . . 49.80m

Main Points on Trimming of Valve Seat

(1)

Before trimming the valve seat, check the clearance between the

valve guide and the valve rod, conduct the trimming where

necessary.

(2)

Trim the width and angle of the valve seat to the specified value

with the Muller.

(3)

Grind the valve seat with the corresponding valve with grinding

paste after trimming the valve seat. Then check the protruding

height of the valve stern (refer to inspection items of valve seat).

angle belwee cerrter line of spring and plun bine
of subface

free spring height

1EN0264

valve
guide

inside diamter of
valve guide

outside diameter
of valve guide

1EN0279

endof valve stern

protruding height
of valve stern

seat face of valve
spring

DEN0212

0.9

1.3mm

43.5

44

6EN0491

11-35

ENGINE

CYLINDER HEAD AND VALVE

Main Points in Change of Valve Seat

(1)

Cut out part of the valve seat to be changed so as to thin and

remove it.

(2)

Trim the valve seat holes on the cylinder head as per the outside

diameter of the enlarged valve seat.

Diameter of valve seat ring:

Enlarged dimension: 0.30

34.435-34.455

Enlarged dimension: 0.60

34.735-34.755

Enlarged dimension: 0.30

31.935-31.955

Enlarged dimension: 0.60

32.235-32.255

Diameter of valve guide hole on cylinder head:

Dimension plus 0.05:

11.05-11.068

Dimension plus 0.25:

1.25-11.268

Dimension plus 0.50:

1.50-11.518

(3)

Press the valve guide as shown in the figure until its protrusion

meets the specification.

Standard value: 14mm

0.3

Notice:

Press down the valve guide from the superface of the cylinder

head.

The length of the inlet valve guide is different from that of the

exhaust valve guide. (inlet valve: 45.5, exhaust valve: 50.5

(4)

Inset the new valve after mounting the valve guide and inspect

whether it can move smoothly.

0.5

1mm

1EN0274

0.5

1mm

cut out

height of valve
seat ring

enlarged lnside diameter

1EN0275

protrusion

1EN0106

(3)

Before assembling the valve seat ring, heat the cylinder head to

250 or so, or cool the valve seat ring in the liquid nitrogen so as

to prevent it from being seizing in the cylinder head.

(4)

Trim the valve seat to the specified width and angle with the

milling cutter of valve seat (refer to the Main Points for Trimming

of Valve Seat)

Main Points for Change of Valve Guide

(1)

Press the valve guide out toward the cylinder block with the

presser.

(2)

Process the valve guide hole of the cylinder head to make it reach

the dimension of the enlarged valve guide to be mounted.

Notice:

Do not apply the new valve guide with same dimension with the

dismantled one.

Inlet valve seat

Exhaust valve seat

11-36

ENGINE

CYLINDER HEAD AND VALVE

10N.m

1.0Kgft

27

29

24

26

23

18

19

17

24N.m

2.4Kgifm

22

16

15

14

13

12

11

44N.m
4.5Kgfm

7

8

2

3

6

25

23N.m
2.4Kgfm

36N.m
3.7Kgfm

5

9

39N.m
4.0Kgfm

7N.m
0.7Kgfm

4

19N.m
1.9Kgfm

20

16N.m
1.7Kgfm

10N.m
1.0Kgfm

28

10

N

N

N

N

N

N

21

N

N

N

N

N

N

All inside parts should be
coated with the engine oil

19N.m

1.9Kgifm

Disassembly Process

1. lubricating oil filter

2. drain plug

3. drain plug washer

4. oil sump

5. oil collector and filter

6. washer of oil collector and filter

7. plug

8. o-ring

9. flange bolt

10. oil pressure switch

11. relieve pug

12. gasket

13. pressure relief spring

14. pressure relief plunger

15. oil filter bracket

16. washer of oil filter bracket

17. lubricating pump cover

18. driven gear of lubricating pump

19. driving gear of lubricating pump

20. front oil seal of crankshaft

21. oil seal of lubricating pump

22. oil seal of balancing shaft

23. front cover

24. front cover washer

25. left balancing shaft

26. right balancing shaft

27. front bearing of right balancing shaft

28. left balancing shaft bearing

29. rear bearing of right balancing shaft

N

M

L

A

K

B

I

G

H

H

F

D

E

J

C

C

D

B

E

A

E

FRONT COVER, OIL PUMP, BALANCE SHAFT ,OIL PAN

DISMANTLE AND ASSEMBLY

11-37

Main Points of Disassembly

Disassembly of Oil Sump

(1)

Disassemble all of the bolts of oil sump.

(2)

Tap the SST into the clearance between the cylinder block and

the oil sump.

Notice:

Do not replace the SST with screwdriver or chisel, otherwise the oil

sump will deform and leak oil.

Disassembly of Plug

(1)

In case the plug is over tight, tap it lightly with hand hammer

for two or three times, and it will become loose.

Disassembly of Flange Bolt

(1)

Tear down the plug from the side of cylinder block.

(2)

Insert the screwdriver (with pole diameter of 8mm) in the plug

hole to fasten the balancing shaft.

A

B

C

MD998727

6EN0698

MD998162

6EN0909

6EN1026

screwdrive

plug

ENGINE

CYLINDER HEAD AND VALVE

6EN0565

3EN0207

front bearing

MD998372

D

(3)

Loosen the flange bolts

Disassembly of Front bearing of Right Balancing

shaft

(1)

Dismantle the front bearing of the right balancing shaft from

the cylinder block with the SST.

Remark: The front bearing must be dismantled first, otherwise, the

puller for rear bearing cannot be applied.