Dadi. Engine 4G64 S4M. Service Manual - part 4

11-43

ENGINE

 CYLINDER HEAD AND VALVE

DISASSEMBLY AND ASSEMBLY

Disassembly Procedure

1. connecting rod nut

2. connecting rod cap

3. connecting rod bearing

4. piston and connecting rod cluster

5. connecting rod bearing

6. first air ring

7. second air ring

8. oil ring

9. piston pin

10. piston

11. connecting rod

12. connecting rod bolt

All inside parts must be

coated with engine oil

6EN0526

G

F

A

E

D

E

C

C

B

A

B

11-44

ENGINE

 CYLINDER HEAD AND VALVE

Main Points in Disassembly

Disassembly of Connecting Rod Cap

(1)

Mark the cylinder No. on the side face of the larger end of the

connecting rod so as to ensure the correct assembly.

(2)

Put aside the dismantled connecting rod, connecting rod cap

and connecting rod bearing in order as per the cylinder No.

marked on.

Disassembly of Piston Pin

(1)

Insert the SST of compression bar from the side with arrow

mark at the piston top, then mount the guide block C at the end

of compression bar.

(2)

Keep the mark for forward face of the piston to face upwardly,

and mount the piston and connecting rod cluster on the base

seat (SST) of the assembler of piston pin.

(3)

Press the piston pin out with the pressure.

Notice:

Put aside the dismantled piston, piston pin and connecting

rod as per the cylinder No. marked on.

A

B

cylinder No.

DEN0050

Assembler for Piston Pin MD998780

pressing rod guide block B

conduit A=17.9mm

conduit A=18.9mm

conduit A=20.9mm

conduit A=21.9mm

guide block C

base seat

pressing rod

mark for forward

face

guide block C

base seat

mark for

f o r w a r d

face

7EN0390

7EN0431

11-45

ENGINE

 CYLINDER HEAD AND VALVE

Main Points for Mount

Mount of Piston Pin

(1)

Measure the following dimensions of the piston, piston pin

and connecting rod;

A) Length of inserting hole of the piston pin;

B) Width between the keyway

C) Length of piston pin

D) Width of smaller end of connecting rod.

(2)

Calculate the dimension L by substituting the letters in the

below formula with the measured dimensions:

L

[(A 
 C)
(B 
 D)] / 2

(3)

Insert the SST of compression bar in the piston pin and mount

the conduit A at the end of compression bar.

(4)

Conduct the assembly in such way that the mark for forward

face on the piston is in the same direction with that of the

connecting rod.

(5)

Coat the engine oil on the outside diameter of the piston pin.

(6)

Encase the piston pin, connecting rod and conduit cluster

assembled as Step (3) in the piston pin hole at the side with

mark for forward face with conduit A.

(7)

Screw the guide block B in the conduit A and ensure the

clearance between the guide block B and the guide block A is

the value of the sum of L calculated in Step (2) plus 3 mm..

(8)

Maintain the state that the mark for forward face of piston

faces upwardly, and mount the piston and connecting rod

cluster on the base seat of the assembler of piston pin.

(9)

Press in the piston pin with pressure. If the pressure force is

less than the standard value, Change the piston pin and the

piston cluster, or/and change the connecting rod.

Standard value: 750

1750kg

A

piston

piston pin

connecting rod

A

B

C

D

7EN0432

3mm+L

guide block B

conduit A

7EN0433

compression bar

piston pin

mark for forward face

mark for

f o r w a r d

face

conduit A

conduit B

base seat

7EN0391

11-46

(10)

Check whether the piston can rotate freely.

Mount of oil ring

(1)

Put the main ring of oil ring in the oil ring groove.

Remark:

1. The scraper blade and the main ring has the specified upper./lower

face.

2. The new main ring and scraper are colorful to identify its dimension.

(2)

Put in the upper scraper blade. When mounting the scraper blade,

press one end of the scraper blade in the piston oil ring groove, then

press the remaining part of scraper blade in the oil ring groove

shown as the figure by thumb.

Different from other piston ring, the use of ring pliers to expand the

scraper blade will break the scraper blade.

Notice:

Do not use the ring pliers to expand the scraper blade.

(3)

Mount the lower scraper blade in the same procedure of Step (2).

(4)

The scraper blade should be confirmed whether can rotate freely

to left and right after the mount.

 Mount of First and Second Air Ring

 (1)

The first air ring should be mounted after the second air ring is

mounted with the ring pliers.

Remark:

1. There is identification mark at the ring end.

Identification mark:

First ring

1R

Second ring

2R

2. Mount the piston ring and be sure the identification mark should face

upwardly to the top of the piston.

3. The dimension marks of piston ring are as follows:

6EN0 298

upper scraper blade

main ring

lower scraper blade

6EN1019

Dimension

Identification Color

Standard value

None

0.50mm larger

Red

1.00mm larger

Yellow

clearance of scraper blade

1EN0269

C

Dimension

Dimension mark

Standard value

None

0.50mm larger

50

1.00mm larger

100

ring pliers

7EN0452

identification mark

identification mark

direction mark

first ring

second ring

9EN0524

B

ENGINE

 CYLINDER HEAD AND VALVE

11-47

upper scraper blade

crankshaft

pulley side

openings of second and
main rings

lower balde

6ENO549

D

Mount of Piston and Connecting Rod Cluster

(1)

Coat enough engine oil on the piston, air ring and oil ring.

(2)

Adjust the openings of the air ring and oil ring (scraper blade

and the main ring) to the place shown in the figure.

(3)

Rotate the crankshaft until the crank pin locates the position of

the cylinder hole.

(4)

Threaded protective device should be adopted on the connect-

ing rod bolt before the insertion of the piston and connection

rod cluster in the cylinder. Carefulness is needed not to

damage the crank pin.

(5)

Insert the piston and connecting rod cluster in the cylinder

with the suitable press fitting SST for piston ring.

Notice:

There is a mark for forward face on the top of piston, which should

direct to the front of the engine (timing toothed belt side).

Mount of Connecting rod bearing

Where the bearing is needed to change, it should be selected and

mounted as per the following procedure.

(1)

Measure the outside diameter of the crank pin and determine

which group it belongs as per the following form, the crank-

shaft to be maintained should be marked at the position shown

in the figure with color paint to identify its dimension.

(2)

The identification mark of the connecting rod is printed at the

position shown in the figure.

Inside diameter of connecting rod; 48.000

48.015mm

(3)

Select the bearing from the group determined as per the Step

(1) and (2).

Bearing Selection, for example:

In case the outside diameter of the crank pin is measured as 44.

996mm, it belongs to the Group 1 in the above form. If the

repairing element for crankshaft needs to be changed, inspect

the identification color coated on the new crank pin. If the

color is yellow, the crank pin should belong to the first group,

therefore, the connecting rod bearing marked with 

1

should be selected.

E

timing toothed belt

mark for forward face

1EN0247

NO.1

NO.2

NO.3

NO.4

6EN0700

6AE0115

identification mark

Crank pin

Connecting rod bearing

Yellow

44.995

45.000

1

Yellow

1.487

1.491

None

44.985

44.995

2

None

1.491

1.495

White

44.980

44.985

3

Blue

1.495

1.499

Identification

color

Outside

diameter

(mm)

Identification

mark

Identification

color

Thickness

(mm)

Group

ENGINE

 CYLINDER HEAD AND VALVE

11-48

Mount of Connecting Rod Cap

(1)

When mounting the connecting rod cap, align the marks made

in disassembly well, if mounting the new member without

mark, the anti-rotary gap shown in the figure should be

mounted at the same side

(2)

Be sure the axial clearance at the larger end of connecting rod

is suitable.

Standard value: 0.10

0.25mm

Limit value: 0.4mm

Mount of Connecting Rod Nut

Notice:

  In case the cylinder head is mounted before the mount of

connecting rod cap, dismantle the spark plug and then

mount on the connecting rod cap nut.

(1)

The connecting rod bolts and nuts should be tightened with the

method of tightening bolt at plastic zone. Before reusing the

bolt, check whether the bolt is expanded. Inspection method:

tighten the nut to the threaded part of the bolt by hand until it

passes the full thread. In case the nut cannot be screwed down

to the bottom, it can be judged the threaded part of the bolt may

be protracted, change the bolt on such condition.

(2)

Coat the oil on the threaded part and the seat face of the nut

before tightening the nut.

(3)

Tighten the nut on the bolt by hand and then screw the nuts down

in turns so as to assemble the connecting rod cap correctly.

(4)

Tighten the nut with the torque of 20N.M.

(5)

Coat the paint mark on each nut head.

(6)

Make paint mark on the bolt at the position 90

100

forward from the paint mark at nut head.

(7)

Tighten the nut by a angle of 90

100
, until the marks on

the nut and the bolt are in alignment.

Notice:

 If the screwing angle is less than 90
, the tightening

property specified is cannot be guaranteed. Therefore,

attention should be paid to the screwing angle when

tightening.

 In case the nut is over tightened, (the screwing angle is

more than 100

), loosen it thoroughly, and then re-

tighten it from the Step (1).

F

G

cylinder No.

anti-rotary gap

DEN0051

6EN0621

paint

marks

paint  marks

90

 100

6AE0298

ENGINE

 CYLINDER HEAD AND VALVE

11-49

Inspection

Piston Ring

(1)

Check whether the piston ring has damage, over abrasion

or breakage, if it has, change it, in the case of changing the

piston, the piston ring needs to be changed too.

(2)

Check the clearance between the piston ring and the piston

ring groove, if it is over large, change the piston ring or the

both parts.

Standard value: 0.02

0.06mm

Limit value: 0.1mm

(3)

Put the piston ring in the cylinder and locate it with the

crown face of the piston, then measure the opening clear-

ance with the feeler. If the opening clearance is over large,

change the piston ring.

Standard value:

First ring

0.25
0.35mm

Second ring

0.40
0.55mm

Oil ring

0.10
0.40mm

Limit value:

First and second ring

0.8mm

Oil ring

1.0mm

Play of Crank Pin (clearance gauge of plastic cord)

(1)

Clear away the oil on the journal and bearing of the

connecting rod thoroughly.

(2)

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

the same with the bearing width, and then put them on the

crank handle and parallel them with the axial center line.

(3)

Mount on the connecting rod cap carefully and tighten the

nut as per the specified torque.

(4)

Dismantle the connecting rod cap carefully.

(5)

Measure the max width of the flattened plastic cord with

the gauging ruler printed on the package bag of the clear-

ance gauge of plastic cord, thus obtaining the clearance

value.

Standard value: 0.02

0.05mm

Limit value: 0.1mm

5EN0066

press it in with piston

priston ring

opening clearance

5EN0548

1EN0246

clearance gauge of plastic cord

1EN0271

ENGINE

 CYLINDER HEAD AND VALVE

11-50

ENGINE

 CYLINDER HEAD AND VALVE

CRANKSHAFT, CYLINDER BLOCK AND

FLYWHEEL

DISASSEMBLY AND ASSEMBLY

13

5

6

3

2

11N.m

132N.m

8.8N.m

4

11N.m

11

10

9

8

7

25N.m+90

~100

12

Smear the engine oil on

all moving parts

N

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

E

D

C

C

B

B

A

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

A

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.

B

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

0

1 Green

0 Black

Yellow 56.994

 57.000

1

2 Yellow

1 Green

2

3 None

2 Yellow

0

2 Yellow

1 Green

None

56.988

 56.994

1

3 None

2 Yellow

2

4 Blue

3 None

0

3 None

2 Yellow

White

56.982

 56.988

1

4 Blue

3 None

2

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)

11-54

6EN0624

arrow mark

ENGINE

 CYLINDER HEAD AND VALVE

9EN0477

paint marks

paint marks

90

100

6AE0299

6EN0625

Mount of Main Bearing Cap/ Main Bearing Bolt

(1)

Mount the main bearing cap with the arrow mark thereof

directing to the side of timing toothed belt.

(2)

Be sure the length of bolt is less than the limit value before

mounting the main bearing cap bolt. In case it is larger than the

limit value, change the bolt.

Limit value (A): 71.7 mm

(3)

Coat the engine oil on the threaded part and seat face of the

bolt.

(4)

Tighten the main bearing cap bolt with the torque of 25N.m as

per the specified sequence.

(5)

Make paint mark on each bolt head.

(6)

Screw down the paint mark at the position of the main bearing

cap by 90

100
forward from the paint mark on bolt.

(7)

Tighten each bolt by 90

100
in the above specified se-

quence until the paint marks on the bolts are in alignment with

that on the main bearing cap.

Notice:

 If the screwing angle is less than 90
, the tightening

property specified is cannot be guaranteed. Therefore,

attention should be paid to the screwing angle when

tightening.

 In case the nut is over tightened, (the screwing angle is

more than 100

), loosen it thoroughly, and then re-

tighten it from the Step (1).

(8)

Ensure the crankshaft can rotate smoothly after the main

bearing cap is well mounted, and inspect the axial clearance.

In case the axial clearance exceeds the application limit value,

change the No.3 crankshaft thrusting bearing.

Standard value; 0.05

0.18mm

Limit value: 0.25mm

C

11-55

ENGINE

 CYLINDER HEAD AND VALVE

MD990938

MD998376

6EN0709

6EN0626

Mount of Oil Seal

Mount of Rear Oil Seal Cover

Specified sealant

Brand: Genuine Mitsubishi brand sealant MD970389 or the

equivalents.

Notice:

(1)

The rear oil seal cover should be mounted quickly on the

condition the sealant is not dry (

 15 min).

(2)

Keep the sealing area free from the lubricant and coolant for

1 hours or so after the mount.

D

E

11-56

ENGINE

 AC GENERATOR

AC GENERATOR

1

6

5

4

2

3

7

8

9

10

11

12

13

DISASSEMBLY AND ASSEMBLY

Disassembly Procedure

1.

generator pulley

2.

rotor assembly

3.

rear bearing

4.

bearing block

5.

front bearing

6.

front cap

7.

stator assembly

8.

retaining plate

9.

adjustor and brush stand

10. brush

11. ring

12. rectifier assembly

13. rear cap

A

A

A

B

9EN0187

11-57

ENGINE

 AC GENERATOR

6EN1774

1EN0300

rectifer

soldering joint

DEL0009

6EN0603

6EN0604

NOTES FOR DISASSEMBLY

SEPARATION OF STATOR AND FRONT CAP

(1)

Insert the screwdriver into the gap between front cap and stator

to separate the front cap from the stator.

(2)

If it is hard to separate them, lightly hit the front cap with a plastic

hammer and prize it with screwdriver at the same time.

NOTES:

 Don't insert the screwdriver too deep lest the stator winding

is damaged.

DISASSEMBLY OF GENERATOR PULLEY AND ITS FAN

(1)

With the pulley end upwards, disassemble the pulley after fixing

the rotor with a bench clamp.

NOTES:

 Do not damage the rotor.

DISASSEMBLY OF STATOR ASSEMBLY, ADJUSTOR

AND BRUSH STAND

(1)

Knock down the stator with an electric iron (180

250W), such

operation should be finished within 4 seconds lest heat is con-

ducted to the diode.

(2)

While disassembling rectifier from adjustor, burn off the part

welded to the rectifier with the electric iron.

 Ensure not to conduct the heat generated by the electric iron

to the diode for a long time.

 Do not let the diode pin overburden forces.

CHECK

ROTOR

(1)

Check whether the rotor winding is switched into conduction and

confirm conduction exists between the slip-rings. Measure the

resistance of the rotor. If the resistance is too low, it means the

circuit is shorted . If there exists non-conduction or short circuit,

replace the rotor assembly.

Standard value: 3

 0.5 

(2)

Grounding of rotor winding. Check if it is insulated between the

slip-ring and iron core, if not, replace the rotor assembly.

A

B

11-58

ENGINE

 AC GENERATOR

3EN0208

3EN0209

7EL0011

7EL0012

7EL0012

STATOR

(1)

Conduct on stator examination over the stator and confirm

whether the conduction exists with the lead-wire of the winding,

if not, replace the stator assembly.

(2)

Check the grounding of stator winding. Confirm whether con-

duction exists between the winding and stator iron core, if yes,

replace the stator assembly.

RECTIFIER

(1) Check the positive rectifier

Check whether conduction exists between the positive rectifier

and the wiring terminals of stator windings with a multimeter. If

conduction exists in two direction , the diode is breakdown, the

rectifier assembly should be replaced.

(2)

Check the positive rectifier

Check whether conduction exists between the negative rectifier

and the wiring terminals of stator windings. If conduction exists

in two direction, the diode is breakdown, the rectifier assembly

should be replaced.

(3)

Check diodes group (3 diodes)

Connect the two ends of the diode to the ammeter, check whether

these three diodes are switched into conduction.

If conduction doesn

t exists bidirectioinally, the diodes are

damaged, and the radiator assembly should be replaced.