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Great Wall engine 4G64S4M. Manual - part 14

11-50

ENGINE

CYLINDER HEAD AND VALVE

CRANKSHAFT, CYLINDER BLOCK AND

FLYWHEEL

DISASSEMBLY AND ASSEMBLY

11N.m

132N.m

8.8N.m

11N.m

25N.m+90

~100

Smear the engine oil on

all moving parts

Disassembly Procedure

1. flywheel bolt

2. flywheel

3. rear cover plate

4. bell jar

5. rear oil seal cap

6. oil seal

7. main bearing cap bolt

8. main bearing cap

9. low bearing of crankshaft

10. crankshaft

11. bearing on crankshaft

12. thrust bearing of crankshaft

13. cylinder block

11-51

ENGINE

CYLINDER HEAD AND VALVE

Inspection

Measurement for Crankshaft Play (clearance gauge of plastic

cord)

(1)

Clean the oil on the main journal and the inner race of bearing.

(2)

Mount the crankshaft.

(3)

Cut the clearance gauge of plastic cord in the length that is the

same with the width of bearing, then put them on the crankshaft

journal and ensure them are parallel with the axial center line.

(4)

Mount the main bearing cap carefully and tighten the bolts as

per the specified torque.

(5)

Tear down the main bearing cap.

(6)

Measure the Max width of the flattened plastic cord with the

gauging ruler printed on the package bag of the clearance

gauge of plastic cord, thus acquiring the clearance value.

Standard value: 0.02

0.04mm

Limit value: 0.1mm

Cylinder Block

(1)

Conduct a visual observation for deflects such as scoring, rust

and corrosion, etc. or conduct an inspection with the fluid

testing agent. In case the cylinder block has obvious deflect,

repair or change it.

(2)

Check the plane on cylinder block for warp with ruler and

feeler, and be sure there should be no washer scraps or other

alien materials on the surface.

Standard value: 0.05mm

Limit value: 0.1mm

(3)

In case the cylinder block has over large warp, change or

correct it within the permitted range.

Grinding limit: 0.2 mm

The max sum of thicknesses of the cylinder block and

cylinder head that is permitted to cut out is 0.2 mm.

Height of cylinder block (new): 290mm

(4)

Check whether the cylinder wall has scoring or the cylinder is

seized, in case the requirement is not met, correct (enlarge the

dimension) or change them.

(5)

Measure the inner cylinder and cylindricity of the cylinder

with the cylinder gauge, the cylinder should be corrected by

enlarging the diameter on condition the abrasion is serious,

and change the piston and piston ring. Measurement positions

are shown in the figure below.

Standard value:

Inside diameter of cylinder: 86.50

86.53MM

Cylindricity:

0.01mm

clearance gauge of
plastic cord

6EN0703

6EN0623

9EN0074

12mm

center

bottom

6EN0553

11-52

ENGINE

CYLINDER HEAD AND VALVE

thrusting
direction

piston diameter

6EN0554

6EN1557

Re-boring of Cylinder Diameter

(1)

The diameter for the enlarged piston should be determined

according to the max cylinder diameter.

Identification of piston diameter

Remark: Dimension mark is printed on the top of piston.

(2)

Measure the diameter of the cylinder to be used, the measure-

ment should be conducted in the thrusting direction shown in

the figure below.

(3)

Calculate the reparation dimension of the cylinder diameter

according to the outside diameter of the piston.

Reparation dimension = outside diameter of piston +

(clearance between piston and cylinder)

0.02 mm

(hone grinding)

(4)

Repair each cylinder to the dimension of reparation.

Notice:

When honing the cylinder, in order to prevent the error

caused by the increased temperature, conduct the reparation

as the order below: No.2

No.4 No.1 No.3

(5)

Hone the cylinder to its final diameter (piston diameter +

clearance between the piston and cylinder).

(6)

Check the clearance between the piston and the cylinder.

Standard value: 0.02

0.04mm

Remark:

When repairing the cylinder, the four cylinders should be in the

same dimension, do not only enlarge one cylinder.

Main Points of Mount

Mount of Thrusting Bearing of Crankshaft

(1)

Mount the thrusting bearing of crankshaft (2 sheets) on the 3rd

main shaft hole of cylinder block. Coat a little engine oil on the

surface of thrusting bearing to facilitate the mount.

(2)

The thrusting bearing side with groove should face to the

handle arm of the crankshaft.

dimension

Identification mark

Plus 0.50

0.50

Plus 1.00

1.00

11-53

ENGINE

CYLINDER HEAD AND VALVE

No.3

No.2

No.1

No.4

No.5

6EN0705

identification mark for dimension of main bearing

No.1

No.2

No.3 No.4

No.5

identification
mark of main
bearing hole

dimension mark
of cylinder in-
side diameter

sub-face of cylinder
block

rear end face of cylinder
block

6EN1632

identification mark or color for crankshaft bearing

identification mark or color

6EN1096

groove

upper

lower

6EN1558

Mount of crankshaft bearing

(1)

Select the bearing that meets the dimension of crankshaft main

journal as per the form below.

Bearing Selection, for instance:

In case the identification color of the crankshaft main journal is

yellow, and the identification mark for main shaft aperture is
1, select the Bearings of No. 1,2, 4 and 5 with identification

mark

2 and identification color yellow or the No. 3

bearing with identification mark

1 and identification color

green.

In case there is no identification paint on the crankshaft, measure

the main journal and select the corresponding bearing as per the

measured value.

(2)

Mount the bearing with groove at the side of cylinder block.

(3)

Mount the bearing without groove at the side of main bearing

cap

1 Green

0 Black

Yellow 56.994

57.000

2 Yellow

1 Green

3 None

2 Yellow

1 Green

None

56.988

56.994

3 None

2 Yellow

4 Blue

3 None

2 Yellow

White

56.982

56.988

4 Blue

3 None

5 Red

4 Blue

Combination of crankshaft main journal and
main shaft aperture

I d e n t i f i c a t i o n
marks and colors
for bearings of
Journal 1,2 and 5

Identification
marks and
colors for
bearings of
No 3 journal

Crankshaft main journal

Identification
mark of main
shaft aperture

Groups

Identifica-

tion color

Diameter

(mm)

Content .. 12 13 14 15 ..