Robin DY23, DY27 Service Manual

ROBIN

ENGINE

ROBIN

TO

MODEL

AMERICA,

WISCONSIN

INC.

ROBIN

CROSS REFERENCE LIST

ROBIN

EY 08 EY15 EY 15V EY 20 EY20V EY23 EY28 EY35 EY40 EY45V EY2

1

EY44

18-3

EY EY25

EY27

SIDE

VALVE

OVERHEAD

WISCONSIN

W 1-080 W1-145 W1-145V W1-185 W1-185V Wl-230 W 1-280 W 1-340

W

1-390

W

1

-450V

EY21W EY44W EY 18-3W EY25W

EY27W

VALVE

ROBIN

EH11 EH12 EHl5 EHI

7

EH2

1

EH25

EH30

EH30V EH34 EH34V

EH43 V

EC13V

DY23

DY27

DY30

DY3

5

DY4

1

TWO

CYCLE

DIESEL

WOI-115

WOI-120

WO1-150

WOI-170

wo1-210 WO1-250

WO

1-300

WO 1 -300v

WO1-340 WO

1

-340V

WO1-430V

WT1-125V

WRD WRD

WRD

1-230 1-270 1-300

WRD1-350

WRD1-410

CONTENTS

Section Title Page

r

1.

SPECIFICATIONS

Model

Type

Bore X Stroke

Piston Displacement

Compression Ratio

output

DIN6270NB

output

DIN6270NA Torque kg

DlN6270NB Rotation

Cool

in

g

Lubrication

(

HP/ rpm

(Warnin”)

HP/ rpm

(KW-min”)

-

m

/

rpm

ft.lbs/

rpm

DY23-2D

DY23-2B

DY27-2

Air-Cooled. 4-cycle, Overhead Valve, Single vertical cylinder, Diesel engine

I

75 X 60 mm

(

2.95 X 2.36

(

16.1 1 cain.

/

3600

/

3600

/

2400 2400

265 cc

1

in.

1

)

5.5

/

1

800

(

4.0/ 1800

5.0

/

1

800

(

3.7/

1800

2.46/ 1200

(

17.W 1200

(

1.07/ 2200

1

(

I

I I

70

(

2.76 X 2.36

(

14.04 cu.in.

4.8 / 3600

3.5 / 3600

/

3600

4.2

3.1

/

3600

7.7/

2200

Counterclockwise as viewd from PTO shaft side

X

230 cc

)

60

rnrn

in.

)

4.8

/

(

3.5/ 1800

4.2 / 1800

(3.1

/1800

2.14/ 1100

(15.4/11001

Forced oil lubrication

)

21

1

800

1

Forced air cooling

5.5

(

4.0/ 3600

5.0 / 3600

(

3.7

1.23

(

8.9/

1

Lubricant

Oil Pump

Fuel Injection Pump

Injection Nozzle

Fuel Fuel Feed Fuel Tank Capacity

Combustion System Governor System

Lighting Capacity

Starting System

Dry Weight

I

(63.9

Diesel engine oil. service rank CC or CD

Recoil starter

Ibs.)

Trochoid gear pump

ZEXEL

Automotive diesel

3.2 liters ( 0.84 U.S.gal. Direct injection type

Centrifugal flyweight type

1

2V- 39W/

12V-43W/ 3600

(65.0

PFRIMD55

DLLAI

Gravity

3000

(

Electric starter as option

50PN052

type

Ibs.)

/

2NP1

fuel

(65.0

1

12V

-

39W

/

3000

12V - 43W / 3600

)

30

kg

lbs.) (66.1 Ibs.)

Dimension

LXWXH

329

x

357

x

402

mm

(1

2.95 x 14.06 x 15.82 in.)

Specifications are subject to change without notice.

-1-

339 x 357

(13.35 x 14.06

x

402

x

15.82

mm

in.)

2-

1

MAXIMUM OUTPUT

The maximum output

its

throttle valve fully open after it has been broken in properly. Therefore, a brand-new engine not produce the maximum output.

2-2

The continuous rated output of an engine is the output power at the rated engine speed controlled by its governor system. The operation of the engine at the continuous rated output view point

CONTINUOUS RATED OUTPUT

of

engine life and fuel economy.

is

It

to

2-3

The maximum torque indicates the torque at the output shaft when the engine

producing the maximum output.

recommended, therefore, that the- equipment driven by the engine to be designed

require the engine power less than its continuous rated output.

MAXIMUM

TORQUE

of

an

engine is the output power

or

an engine which has not been broken in properly may

of

the engine operating with

of

the engine running

is

most

favorable

from

the

is

-2-

2

-

4

PERFORMANCE

CURVES

MODEL

DY23-2

HP

5

4

I

!z

23

W

v)

IT

0

I

2

1

FUEL CONSUMPTION

\

I

1500

(750)

L

2000

(1000)

REVOLUTION

TORQUE

2500

(1250) (1500) (1750) (2000)

"----+

RATIO

L

(NB)

I

3000

\

r.

p.

I

3500 4/00

rn.

kg

1.2 (2.4)

1.1

(2.2)

1

.o

(2.0)

i

(1.8)

z

0

I-

y

g

W

2

c1:

O

I-

g/HP-h

-

3.9

240 220 200

&

22

-

m

MODEL

DY27-2

6

HP

5

4

I

9

5

0-3

W

v)

I1I

P

2

1

(

1

for

B

type

.3 .2 (2.4)

.1

.o

(2.6)

(2.2) (2.0)

kg-

Y

m

2

g/

HP-

h

1500 2000

(750)

(1000)

REVOLUTION

2500

(1250) (1500)

3000

c

r. D.

-3-

3500

(1

750)

rn.

41

(21

3.

FEATURES

3-

1

ECONOMICAL RUNNING

The direct injection system using the newly developed micro fuel injection pump assures superior combustion efficiency and minimized fuel consumption.

3-

2

EXTREMELY QUIET OPERATION

0

The precisely synchronized fuel injection and refined combustion chamber allow lower combustion pressure which results in reduced combustion noise.

Q

Blower housing and cylinder baffle are made from “DUMPING material for insulating noise and vibration.

0

Larger super silent muffler and double element air cleaner reduce the exhaust and intake noise.

3-

3

EASY STARTING

8

Light pull recoil starter and centrifugal automatic decompressor allow effortless

starting similar to a gasoline engine.

0

An auxiliary fuel inlet is provided for easy starting in cold weather.

An

air check valve

3-

4

LESS

0

In

addition to the reduced weight

adopted for extremely smooth running with less vibration.

a

The automatic decompressor prevents shaky vibration at stopping.

VIBRATION

for

easy

air

bleeding

from

the fuel line.

of

reciprocating parts, a balancer shaft has been

SHEET”,

a special

3-

5

HIGH PERFORMANCE

Die-cast cylinder head generates high output power and an exceptional fuel economy.

Its

flat torque characteristic provides tenacious running from slow speed to high speed.

3-

6

SUPERB RELIABILITY

The advanced Robin technology, such as well proven crankcase design, tension bolt system service life under the toughest operating conditions.

3-7

The newly developed micro fuel injection pump and crankcase structure originated in the gasoline engine have .minimized the size and weight of the engine.

3-8

Robin’s new air - cooled diesel engine series assures maximum adaptability to any application.

0

Direct output type Selection

Variable muffler exhaust direction.

0

Recoil starter and optional electric starter.

0

Strong power from small and lightweight body.

Q

Lower noise and less vibration.

for

joining cylinder and cylinder head, and forced lubrication system, for longer

SMALL AND LIGHTWEIGHT

WIDE RANGE

of

P.T.O.

OF

APPLICATIONS

(D

type) and reduction type

shafts for various applications.

a

stable swirl of air-fuel mixture which results in the

(B

type) are available.

-4-

4.

GENERAL DESCRIPTION

OF

ENGINE

CONST

4-1

The cylinder and crankcase are single piece

aluminum die casting. The cylinder liner,

made of special cast iron, is built into the alminum casting. The crankcase is separable shaft side, where the main bearing cover

is

CYLINDER

attached to

4-2

The main bearing cover made die casting is built onto the output shaft side of the crankcase of the engine can readily be checked by simply removing the cover. It is provided with a flange and mounting machines, such and pumps. Two oil gauges also serving caps can be mounted.

MAIN

(See Fig.

2)

AND

it.

BEARING COVER

CRANKCASE

(See

so

boss

Fig.

for directly

on

the output

1.)

of

aluminum

that the inside

as

generators

as

oil filler

4-

3

CRANKSHAFT

Crankshaft is made from forged carbon

steel and its crankpin and journal are

induct ion Crankshaft at flywheel side and a kelmet bearing at

P.T.0:

A

passage for lubricating oil is provided through the journal and crankpin to lubricate the large end bearing of connecting rod. The crank gear is pressure-fitted

P.T.O. side of the crankshaft.

A

balancer gear is also pressure-fitted

for the engines with optional balancer.

(See Fig.

-

side.

3.)

hardened.

is

supported

by

a ball bearing

on

the

~~

FIG.

2

3

-5-

4-4

CONNECTING

ROD

Connecting

rod

is made from forged aluminum alloy which withstands high combustion pressure and tension under heavy load and high speed operation. Kelmet bearings are provided as large end bearing, while the material rod itself serves

(See Fig.

4-

5

Piston

4.)

PISTON

is

casting, and

made from aluminum alloy

it

as

has three grooves

small end bearing.

of

connecting

for

piston

rings.

On

the piston top, a combustion chamber is arranged where the injected fuel mixes with air and ignites.

so

The piston profile is minimize piston noise. (See Fig.

designed as to

5.)

FIG.

,

4

TOP RING

SECOND RING

OIL RING

4-6

PISTON

RINGS

Piston rings are made from special cast

of

iron. The profile and that

of

second ring is taper with

top ring is barrel face,

under cut. The oil ring is the combination of cutter rings and an expander which

is

excellent in gas sealing and reducing

oil

consumption. (See Fig.

4-7

Cylinder head

of

CYLINDER

HEAD

is

the most important part

the diesel engine. It

5.)

is

made from onepiece aluminum alloy die cast, in which intake and exhaust ports, rocker arm room, and cooling fins are molded in the most ideal structure

for

the highest strength and the highest cooling efficiency. High quality heat resistant valve seats are pressure- fitted considering high

resistance to abration and corrosion at high temperature. (See Fig.

6.)

FIG.

,

CONNECTING ROD

5

,-

6

-6-

4- 8 CAMSHAFT

Camshaft for special cast Camshaft for

PTO

shaft and is made from forged carbon

steel and the cam gear

"D"

type engine is made

iron

integrated with cam gear.

"B"

type engine

is

pressure-fitted. Camshaft has three cams, one for intake, one

for

exhaust, and one

pump.

A

release lever for centrifugal

decompressor

(See Fig.

4-

9

7.)

TAPPEU

is

assembled to the camshaft.

€or

Tappets are made from sintered steel. They are precisely finished

after

sintering.

(See

Fig.

by

8.)

from

works

injection

grinding

as

I

FIG.

7

4-

10

VALVE

Valves are made from

forged

heat resistant alloy. Stellite

is

fused to the head

of

valve for added durability. (See

exhaust

Fig.

9.)

EXHAUST VALVE INTAKE VALVE

FIG.

8

9

-7-

4-

11

ROCKER ARM

Rocker arms are made from forged steel and are wholly sintered.

A

screw for adjusting valve clearance is

of

provided at the end Rocker arms are lubricated

in

contained crankcase.

4-

12

ROCKER COVER

the breathing air from

(See

Fig. lo.)

rocker arm.

by

the oil mist

Rocker cover is made from steel sheet.

A

breather plate

is

installed in the rocker

cover to breath air into intake port.

(See Fig.

1

1.)

I

FIG.

10

4-

13

AUTOMATIC DECOMPRESSION

SYSTEM

Automatic decompression system posed

of

a release lever and a flyweight

assembled to the comshaft.

Below

lever

release compression.

the predetermined speed, the release

lifts

the exhaust tappet slightly to

(See

Fig. 12.)

is

com-

-8-

FIG.

11

/-

12

4-

14

GOVERNOR

SYSTEM

The governor is

a

centrifugal flyweight type which permits constant operation at the selected speed against load variations by controlling the quantity of fuel injected. Governor system

is

driven by the governor

GOVERNOR LEVER

gear engaged with cam gear.

(See Fig.

Refer

4-

15

13.)

to

section

6-

LUBRICATION

4

for details.

SYSTEM

FIG.

13

Lubricant is forcibly supplied by the trochoid pump to the crank journal and crankpin. Other rotating

parts

and moving parts are lubricated by the splash

of

oil.

Lubricant (engine oil) is wholly filtered by the oil filter installed on the main bearing cover. The trochoid pump

is

driven by the governor gear.

c

4-

16

COOLING

Cooling air

and cylinder head guided

Fuel injection pump is

is

driven

by

SYSTEM

is

forced

the camshaft.

by

the flywheel fan to blow through

by

the blower housing and the cylinder baffle.

BOSCH

type and

the

cooling fins of cylinder

The fuel from the tank is pressurized by the injection pump and is supplied

to

the injection nozzle through the high pressure pipe. (See Fig.

14.)

-9-

FIG.

14

4-18

FUEL

INJECTION NOZZLE

Fuel is injected in the combustion chamber as fine mist through the

of

fuel injection nozzle. (See Fig.

four

small ports

15.)

FIG.

15

4- 19

Air

AIR

cleaner is

CLEANER

dry

type double element system. Primary element is polyurethane foam and the secondary element is paper. The air cleaner cover

is

made from high strength plastic and its air inlet is specially designed to reduce intake noise.

(See Fig.

4-

20

Fuel filter type. outlet the bottom. (See Fig.

16.)

FUEL

Its

has

on

the top and

FILTER

is

a

paper element disposable

a

automatic air bleeding

a

water drain on

17.)

PRIMARY ELEMENT

FIG.

SECONDARY

/

16

ELEMENT

/

FIG.

17

-

10-

4-

21

COMBUSTION

SYSTEM

For

lower fuel consumption and easy

starting

of

the .engine, the

direct

injection system is adopted in the combustion chamber.

4-21-4

(1

1

SWIRL

FORMING

AND

COMBUSTION

(Inspiring swirl)

OF

COMBUSTION

In order to promote mixing injected fuel and air under the direct injection system, swirl flow is utilized for good combustion. Swirl is spiral flow generated in the cylinder during inspiring stroke, and it decreases during compressing stroke but it still remains and promotes mixing of fuel and

air

toward ignition timing.

Spiral flow by the shape of intake called helical port

of

air (swirl) is generated

port,

or

spiral port.

which is

Tail end of intake port, i. e. upper part

of

intake valve seat, is made in the

spiral forrn : and while the inspired air

is

passing through this part, swirl is

generated around the intake valve. Thus, intake port plays an important role

in

generating swirl.

(See

Fig.

GAS

of

air

19.)

FIG.

/INTAKE

19

/c

SQUISH

INTAKE

SWIRL

CY

LlNDER

PISTON

VALVE

PORT

SQUISH

(Squished

air

flow)

In the piston, combustion chamber (dish type combustion chamber) When the piston comes up to

dead center), air in the

gaps

is

formed.

TDC

(top

is squished

FIG.

20

in the combustion chamber and air flow is generated, which is called “squish.”

(See Fig.

FORMING

20.)

OF

COMBUSTION GAS AND COMBUSTION

For igniting quickly the fuel injected from the nozzle, it is essential to atomize very fine fuel particles for distributing evenly in the combustion chamber.

For

this purpose, fuel should be injected through hole type nozzle by very high

pressure, i. e. 195 kg/c

m’.

The fuel, thus injected, is ‘mixed with air by the flow of swirl and squish while piston is coming up. Accompanying crimb of the piston, combustion gas compressed further and finally it automatically begins igniting and while piston

is

going down,“squish” functions and promotes combustion.

-

11

-

4-

22

SECTIONAL VIEW

OF

ENGINE

INTAKE VALVE

/

EXHAUST VALVE

k/

CYLINDER

PISTON

MA‘N

CRANKSHAFT

TROCHOID

HEAD

BEARING

OIL

COVER

PI

JMP

/

FLYWHEEL

\

CRANKCASE

-

12

-

\

GOVERNOR

ROCKER COVER

AIR CLEANER

MUFFLER

\

/

PUSH

PISTON

PISTON RING

PUMP

ROD

FUEL

INJECTION

TAPPET

BALANCER

'

CAMSHAFT

OIL

GAUGE

\

OIL

DRAIN

-

13

-

5.

DISASSEMBLY

5-

1

PREPARATIONS AND

(1)

When disassembling the engine, memorize well the locations of individual parts that they can be reassembled correctly.

AND

REASSEMBLY

SUGGESTIONS

If

you

are uncertain

of

identifying some parts,

it is suggested that tags to be attached to them.

(2)

Have boxes ready to

(3)

To

prevent missing and misplacing, temporarily assemble as much as possible each

group

(4)

Carefully handle disassembled parts, and clean them with washing oil.

(5)

Use the correct tools in the correct way.

5-2

SPECIAL

or

set

of

TOOLS

disassembled small parts such as bolts and nuts,etc.

keep

disassembled parts by

group.

/-

so

Tool

209-

95001 - 07

228-

95003-

No.

07

Tool

Flywheel puller with

Piston ring cqmpressor

PISTON

RING

COMPRESSOR

f

bolt

Use

For pulling

For placing piston ring

off

the

flywheel

.

FIG.

-

14

21

-

FLYWHEEL

PULLER

/-

5-

3

-DISASSEMBLY PROCEDURES

-

Step

-

1

Engine oil

2

Fuel

-

3

Injection pipe

(1)

(2)

(1)

Proocedures

Remove drain plug and discharge oil from crakcase. Drain plugs are located on both sides of the crankcase.

To

discharge oil quickly, remove

oil gauge. Remove drain plug from fuel

filter and discharge fuel from fuel tank.

Loosen the two joint nuts at the both ends of injection pipe

to

remove it.

Remarks

Be careful not to lose the gasket.

Be careful

to

keep the inside of the pipe, injection pump and the nozzle free of dust.

Tool

14

mm

spanner

10

mm

spanner

12 mm

spanner

INJECTION

PIPE

/

-

15

-

Step lPart to remove

’

4

Air cleaner

Procedures

(1)

Remove cleaner cover from the

cleaner body.

(2) Loosen the wing bolt to remove

element.

(3)

Remove cleaner body from intake manifold.

6

4

X

12

mm flange bolt...-..2pcs

8

0

BOLT and WASHER

Remarks

Be careful not to lose the washer and the

for

packing bolt.

wing

.

Tool

10 mm

box wrench

12 mm

box wrench

I

Step I Part

5

Recoil

to

remove

starter

I

(1) Remove

blower housing.

6

4

Procedures

recoil

x

10

mm flange bolt**..**4pcs.

starter

from

PACKING

ELEMENT

I

CLEANER BODY

Remarks

3

spanner

FIG.

-

16

HOUSING

24

-

6

0

FLANGE BOLT

:

4pcs.

m

RECOIL STARTER

step

I

Part

to

remove

Procedures

I

Remarks

Tool

6

7

Fuel

tank

Muffler

6

+

BOLT

(1)

Disconnect fuel pipe from fuel

(2)

Disconnect fuel return pipe.

(3)

Disconnect rubber pipe from the check

tank.

valve.

(4)

Remove

8

(1)

Remove the muffler cover from muffler.

6

(2)

Remove the muffler.

8

:

4pcs.

the

fuel

tank.

Q

X

20mmbolt*****e.e* 1 pce.

@

X30mmbolt*****~***2pcs.

@

X

10

mm bolt

@nut

9

e

*

4

pcs.

Qspringwasher*****~*~~2pcs.

a

/

+

BOLT

Be careful gasket.

not

to

lose the

10

mm

spanner

12

mm

box wrench

-

17

-

Step Part to remove Procedures Remarks Tool

8

Starting motor

9

Fuel filter

10

Blower housing

(1)

Remove the wire harness from Reattach the terminal 1Omm the starting motor. nut to the motor to spanner

(2)

Remove the starting motor from keep crankcase.

8

4

x

30

mm bolt

(1)

Remove the fuel filter from the Wipe off spilt fuel blower housing. thoroughly. box wrench

6

q-5

X

20

mm flange bolt.....*2pcs

(1)

Remove the blower housing from crankcase.

8

q5

x

20

mm bolt and washer

...............

.....................

2pcs.

.

2pcs.

it

from missing. 12mm

spanner

10

mm

12 mm

box wrench

-

18

-

Step

Part

to

remove

Procedures

Remarks

Tool

11

Flywheel

(1)

Remove the starting pulley.

6

,$

X

12m

(2)

Remove the flywheel nut.

(See Fig.

(3)

Set the flywheel puller to the flywheel. ( See Fig.

27.)

bolt

.......

28.

.....

)

Turn the center bolt clockwise to

pull out the flywheel.

(4)

Remove the key from crankshaft.

...

3pcs.

Flywheel can easily be removed

by

striking with a hammer the head of the center bolt of

flywheel puller. Be careful not to

lose the key.

10

mm

box wrench

24

mm socket wrench

FIG.

27

6

+

FLANGE BOLT

STARTING PULLEY

v

FIG.

28

:

3pcs.-@

FLYWHEEL

SPRING WASHER

NUT

FIG.

-

19

FLYWHEEL

29

-

Step

-

12

13

Part

to

remove

Cylinder baffle

Rocker cover

Procedures

Remarks

Tool

(1) Remove the cylinder baffle from

cylinder.

6

q5

X

10

~~

(I)

Remove the rocker cover from cylinder head.

6

4

mm flange bolt-.-..-lpce.

X

40

mm flange bolt-......lpcs

.

10

box

mm

wrench

Fuel injection nozzle

6

4

NUT

:

NOZZLE BRAC

FUEL

INJECTION

2pcs.

”-e9

NOZZ

(1)

Remove the bracket, nozzle.

6

4

(2)

Remove the fuel injection nozzle

from

I

..............................

nut 2pcs.

cylinder head.

Be careful not to lose

the gasket at the bottom end of the nozzle.

-6

ROCKER COVER

4

FLANGE

BOLT

:

4pcs.

LANGE

BOLT

FIG.

-20-

30

Step Part to remove

15

Rocker arm

16

Cylinder head

Procedu.res

(1)

Loosen the adjusting bolts on the rocker arms.

(2)

Push

the rocker arms.

(3)

Remove the push

(1)

Remove the cylinder head cylinder. spacer.

the rocker shaft out from

cylinder

8

4

flange nut

head to remove

rods.

.......

.....

the

from

.

....

4pcs.

8

6

FRANGE NUT

Make the rocker arms and push rods distinguishable intake side and exhaust side.

Be careful of the

Remarks

:

4DC.s.

of

Tool

10

mm

spanner screw driver

12

mm

socket wrench

ADJUSTING

BOLT

P

ROCKER

CYLINDER

HEAD

\

I

ARM

ROD

-

FIG.

21

32

-

Step

-

17

-

18

)art

to remove

Fuel injection pump

Main bearing cover

Procedures

(1) Remove the fuel injection pump

from crankcase.

6

4

nut

..............................

2pcs.

(1) Remove the bolts joining the

main bearing cover and crankcase.

8

@

X

35

8

@

(2)

Lightly tapping with a plastic

mm bolt..-.----.--. 1 lpcs.

x

40mm bolt

...............

1 pce.

hammer, remove the main bearing cover from the

Fig.

crankcase. (See

33.)

Remarks

Be

careful of the position of the control

Be careful not

rack.

to

damage the oil seal.

Tool

10 mm socket wrench

~ ~~

12 mm box wrench

plastic hammer

6

+

NUT

:

2pcs.

Step

19

20

'art to remove

F

Camshaft

Balancer

(Optional

part)

Procedures

(1)

Remove the camshaft from the crankcase. (See

(2)

Remove the tappets from the

Fig.

crankcase.

i

(1)

Remove the balancer from the

~

crankcase.

35.)

Remarks

(1)

To

prevent the tappet from falling and getting damages, put the crankcase injection pump side down.

(2)

Put marks on the tappets to distinguish intake tappet

from

exhaust. Be

careful

of

the spacer on the balancer shaft.

Tool

SPACER

FIG.

-

23

36

-

Step

21

r

'art

to

Connecting rod

remove

Procedures

(1)

Scrape off the carbon deposit from the piston top and cylinder.

(2)

Remove the connecting rod bolts and the large end cap.

(3)

Turn the crankshaft to the top dead center. Then, push the connecting rod

up and pull the piston and connecting rod out from the cylinder.

Remarks

10

box

Tool

mm

wrench

22

PISTON

Piston and piston pin

RING

(

1)

Remove the two clips from the piston at the both ends

of

pin.

(2)

Push the piston pin out from the piston. Remove the piston from the connecting

(3)

Remove the piston rings from

rod.

the piston by spreading their open ends.

CLIP

piston

Be careful not to give damages to the piston and connecting rod.

Be careful not

to

break the rings by spreading too much or twisting them.

CONNECTING

LARGE

END BEARING'

ROD

/

I

IU

I

/

Step

Part

to

remove

Procedures

Remarks

Tool

23

Crankshaft

FIG.

(1)

Lightly at the flywheel side plastic hammer to remove it from the crankshaft.

(See

Fig.

tap

the crankshaft end

38.)

38

using

a

The ball bearing

comes

crankshaft.

off with the

CRANKSHAFT

\

t

FIG.

39

-

25

-

Part to remove Procedures

Step

I

Intake and exhaust valve remove the retainer locks from

(1)

Press the valve springs and the valve stems. (See

(2)

Remove the valves from the cylinder head.

Fig.

40.)

Remarks

Put marks on the valves, valve springs and spring retainers to distinguish them

for

intake side from

exhaust side.

Tool

~~ ~

.pliers

3

Oil

h

filter

FIG.

(1)

Remove the oil filter from the Be careful not to lose main bearing cover. the

6

4

40

X

12mm

flange bolt...---2pcs.

0-

10

mm

ring. spanner

8-

I

&“----

RETAINER

STEM

LOCK

SEAL

MAIN

BEARING

COVER

7-

OIL

FILTER

6

+

FLANGE

J

FIG.

41

-

26

-

BOLT

:

2pcs

VALVE

EASSEMBLY

PROCEDURES

PRECAUTIONS

FOR

REASSEMBLING

(1)

Clean parts thoroughly before reassembly.

(2)

Scrape

off

all

carbon deposits

from

cylinder head, piston top and piston ring grooves.

(3)

Check lips

of

oil

seals. Replace

oil

seal

if

a

lip

is

damaged.

(4)

Replace all gaskets with new ones.

(5)

Replace keys, pins, bolts, nuts, etc.,

if

necessary.

(6)

Torque bolts and nuts to specification refering to the “Table

of

tightening torque”.

(7)

Apply

oil

to

rotating

and

sliding portions.

(8)

Check

and

adjust clearances and end plays where specified in this manual.

Pay most attention to cleanliness

of

piston, cylinder, crankshaft, connecting rod

and

bearings.

Apply

oil

to lips before reassembly.

5-

4- 1 CRANKSHAFT

(1)

Fit the oil seal guide

onto

the

end

of

the crankshaft, and insert the

crankshaft

into the crankcase.

U/

OIL

SEAL

GUIDE

FIG.

42

-

27

-

5-

4-

2

PISTON AND PISTON

(1)

If

the piston ring expander is unavailable, install the piston rings

ends

to

1.

Pay attention not to break the piston

2.

Install the oil ring first followed

3.

Second

have to face upward when installed on

over

slip

the

top

land

them into the correct ring grooves.

ring have “N”marks stamped on

RING

of

the piston and

spreading

ring

by twisting.

by

the second ring and then top ring.

the

ring

the

piston.

the

ends. These

ring ends

”N”marks

by

placing

only

far

the

enough

open

I

(2)

Assemble the piston and connecting

OPEN ENDS PISTON

Top ring

Second

Oil

RING

FIG.

43

ring Cutter

FIG.

rod

OF

‘

ring

I

Barrel face

Taper

ring

44

with the piston pin.

with

expander

......

...

...........

....................

.........

:e

......

.......

................

......

...........

..........

1.

Set the “D”or “B”mark stamped on piston top connecting

2.

Apply

3.

Be

sure

enough oil to the

rod.

to set

the

clips

small

on

both ends

end of the connecting rod.

of

-

28

the piston

-

to

the

“FAN”mark

pin.

side

of

I

the

,

assembly into the cylinder. Use the piston ring compressor

to

hold the piston rings. The “FAN” mark

of

the connecting rod have to face flywheel side when assembled. (See Fig.

45.)

1.

Apply enough oil to the piston rings, connecting rod bearings and cylinder

bore before assembly.

2.

Set the open end

of

the piston rings

90

degrees apart from

one

another

before assembly.

5-4-3

CONNECTING

ROD

(1)

Turn the crankshaft

to

the bottom dead center, lightly hammer the piston head until the connecting rod contacts

the crankpin, and assemble,

(2)

When reassembling the large end cap, match the alignment mark

on

the rod.

1.

No.

lock washer

is

used for the

2.

Tighten the rod bolts securely

by

the

Tightening torque

:

180-200

Kg-

cm

connecting

rod

bolts.

specified tightening torque.

PlSTON

RING

COMPRESSOR

FIG.

45

FIG.

46

-

29

-

5-

4- 4

BALANCER (Optional part)

Install the balancer to the crankcase. Align the matching marks gear and crank gear as shown in Fig,

of

the balancer

47.

FIG.

47

-I

AFT

5-4-

(1)

(2)

5

TAPPET AND CAMSHAFT

Insert the tappets into the tappet holes

of

the crankcase.

Be sure to assemble the intake tappet

to intake side and exhaust tappet to

exhaust side.

Install the camshaft into the crankcase matching the timing marks crank gear and cam gear. (See Fig.

on

the

48.)

FIG.

48

,

-

30

-

5-4-

6

MAIN BEARING COVER AND GOVERNOR GEAR

(1)

Installation

of

governor gear

shaft

set.

MAIN BEARING COV VERNOR

GOVERNOR GEAR

S

243-4501 1-01

(GOVERNOR GEAR SHAFT

FIG.

49

GEAR

SET)

a) Insert

GOVERNOR

GEAR

SHAFT

to the main bearing cover.

b)

Put

GOVERNOR

GEAR

on

the governor gear shaft.

c) Press

the

iron sleeve

of

governor gear using

a

pressing machine

to

fit

on the governor

gear shaft. (See

Fig.

50.)

Be sure to make a clearance

of 1 mm

(0.04

in) between governor gear and mounting

boss

of

main

bearing cover. (See Fig.

5

1.)

FIG.

50

FACE

OF

MAIN BEARING COVER

S

THE IRON SLEEVE

OVERNOR GEAR

I

CLEARANCE

1

rnm

(0.04in)

FIG.

51

1.

When replacing the governor gear or governor gear shaft, be sure to replace them

2.

Do

not press the plastic part

of

governor gear at assembling.

at the same time.

-

31

-

(2)

Install the main bearing cover

to

the crankcase. Adjust the side clearance for the crankshaft, camshaft specified values using the proper spacer and

thrust

and

washer.

balancer shaft to

the

SIDE CLEARANCE

ADJUSTING DEVICE

CRANKSHAFT

0.1

-0.3

THRUST

T

WASHER

=

0.1

=

0.2 mm

=

0.3

mm

.

D

type

I

0.05-0.25 mm

SPACER

T = 0.8

T=

1.0

CAMSHAFT

I

mm mm

type

0.05-0.3 mm

SPACER

T = 0.6 T

=.0.8

T

=

1.2

mm mm mm

BALANCER SHAFT

I

0.05-0.25 mm

SPACER

T

=

0.8

T

=

1.0

T

=

1.2

I

mm mm mm

A

-

32

,

-

1.

As the governor gear is mounted on the main bearing cover side, install the main bearing cover while checking that

it

meshes

with

the teeth of the

cam gear.

(See

Fig.

53.)

2.

If

the replacement of oil seal is necessary, press-fit the new oil seal before installing the main bearing cover.

3.

Apply oil to the ball bearing and

oil

seal rip before installing the main bearing cover.

4.

Be careful not to injure the oil seal rip at reassembly.

Use

oil seal guide

to protect

it.

1

FIG.

53

(3)

Tighten the twelve bolts evenly to join the main bearing cover

to

the crankcase.

8

@

X

35

mm

bolt and washer assy.

-

1 lpcs.

8

q5

X

40

mm bolt and washer assy.

.

* * * *

-

1

pce.

Tightening torque

:

170-190 kg- cm

Attach the two clamps to

the

main bearing cover

for

electric start model.

5-4-*7

FLYWHEEL

AND

STARTING

PULLEY

(1)

Put

the woodruff key (for magneto) in place.

(2)

Wipe off oil and grease thoroughly

from

the tapered portion

of

the crankshaft and

flywheel center hole.

(3)

(

ELECTRIC

START

MODEL

)

'

Install the charge coil to the crankcase.

(4)

Install the flywheel to the crankshaft. Tighten the flywheel nut with

a

spring

washer.

Tightening torque

:

600-650

kg-

cm

(5)

Attach the starting pulley to the flywheel.

6

@

x

12mm bolt and washer

assy.

-. . -.

3pcs.

'Tightening torque

:

70-90 kg-cm

-

33

-

5-4-8

(1)

FUEL INJECTION PUMP

Measure the distance between the face

of

the cam base and the pump

mounting face of the crankcase.

(See

Fig.

54.)

Select the gasket (injection pump) the proper thickness to be adjusted to

so

as the distance

66

-+

0.05mm. The gasket (injection pump) of three different thickness are available.

(T

=

0.1

mm,

(2)

Apply

to the both side

pump).

T

sealant

=

0.2

mm

and

(THREE BOND

of

the gasket (injection

T

=

0.3

of

mm)

1215)

FIG.

54

(3)

Install the fuel injection pump to the crankcase checking the control rack of the injection pump to engage with the governor lever correctly.

(See Fig.

55.)

FIG.

/-

55

-

34

,

-

5-4-9

CYtlNDER

HEAD

(1)

Assemble the intake valve and exhaust valve to the cylinder head.

a) Remove carbon deposits from valves,

valve seats, intake and exhaust

ports,

and valve guides.

b)

If

the valve face

is

worn out, replace

it

with

a

new one.

c) Check the stem seal in the intake valve

guide for

a

damage.

If the rip of the stem seal is injured,

replace

it

with a new one.

d) Insert the intake valve and the exhaust

valve into the valve guide.

e)

Assemble the valve springs, spring retainers and the retainer locks.

(2)

Check the clearance between the piston top and the. cylinder top.

(See Fig.

56.)

Select the proper SPACER (head)

so

as the clearance to be within

0.6-0.7

mm.

SPACER (head) of two different thickness

(T

=

0.6

mm and

0.7

mm)

are

available. (See Fig.

56.)

(3)

Put the cylinder head on the cylinder.

(4)

Apply

sealant (THREE

BOND

1215) to the two studs on the rocker shaft side. Apply oil to the other two studs.

(See

Fig.

57.)

(5)

Tighten the four flange nuts evenly in three steps by the following tightening torque.

100 kg-cm

200

kg- cm

300-330 kg-

cm

1st step

.............

2.nd step..

...........

3rd step

.............

5-4-

10

ROCKER

ARMS

(1)

Insert the push rods into the tappets

in

FIG.

56

I

APPLY

THREE

BOND

1215.

FIG.

57

the crankcase.

(2)

Apply oil to the rocker arms and install them to the cylinder head using the rocker shaft. Attach the snap rings to the both ends of the rocker shaft.

-

35

-

5-

4-

11

VALVE CLEARANCE ADJUSTMENT

(1)

Set the crankshaft to the top dead center by matching the mark flywheel with the

"TOP"

"T"

of the

mark of the

crankcase.

(2)

Loosen the lock nut on the rocker arm and turn the adjusting

screw

to adjust the clearance between the rocker arm and valve stem end to

0.1

mm.

(both intake and exhaust)

Then, tighten the lock nut.

Adjust the valve clearance while 'the

is

engine

cold.

(3)

Turn the flywheel

by

hand and check the valves move smoothly without hitting piston.

0

INTAKE, EXHAUST VALVE TIMING

The valve clearance shall increase to

0.4

mm while engine is running hot.

In

this condition, the valve timing

follows

:

is

Intake valve opens at 16" before TDC.

Intake valve closes at Exhaust valve opens at Exhaust valve closes at

54"

14"

after BDC. before

after

BDC. TDC.

as

TDC (TOP DEAD CENTER)

INTAKE VALVE

FIG.

16"

58

14"

EXHAUST VALVE

(4)

Apply

the joining surface

(5)

Install the rocker cover and the gasket

sealant

(THREE

of

the

BOND

rocker cover.

(rocker cover) to the cylinder head.

1215)

to

-

36

-

INTAKE VALVE

CLOSES.

BDC (BOTTOM DEAD CENTER)

FIG.

59

,

5-

4-

12

FUEL

INJECTION NOZZLE

(1)

Insert the nozzle assembly into the cylinder head attachi-ng the gasket

(nozzle) to the nozzle

tip.

(2)

Attach the fuel return pipe to the injection nozzle.

(3)

Attach the BRACKET (nozzle

2)

and

BRACKET (nozzle

l),'

and tighten the two nuts with spring washers tentatively.

(4)

Attach the fuel injection pipe

to

the injection nozzle and the injection pump. Tighten the lock nuts tentatively.

(5)

Tighten the two nuts on the BRACKET

(nozzle

1).

Tightening torque

:

50-60

kg- em

(6)

Tighten the lock nuts

on

both ends

of the injection pipe.

I

SPRING

WASHER

FIG.

60

5-4-

13

CYLINDER BAFFLE

AND

BLOWER HOUSING

(I)

Attach the cylinder baffle to the cylinder.

(2)

Attach the blower housing to the crankcase. Tighten the upper two bolts tentatively because these bolts shall be used for mounting fuel tank afterwards.

5-4-

14

MUFFLER

(1)

Attach the muffler cover to the muffler.

(2)

Attach the muffler and the gasket (muffler) to the cylinder head. Tighten the bolt and

nuts

tentatively.

5-4-15

FUEL TANK

(1)

Attach the fuel pipes to the fuel tank.

(2)

Install the fuel tank to the engine. Tighten the bolts and nuts for joining the blower housing and the muffler to the cylinder head at this step.

-

37

-

5-4-16

FUEL

PIPES

(1) Attach the fuel filter to the blower housing.

(2)

Attach the fuel pipes between the fuel tank, fuel filter, injection pump and the

injection Clamp the each end of rubber pipes

nozzle.

using

the proper hose clamps.

,r

5-4-

(1)

5-

17

AIR CLEANER

Attach the cleaner

(2)

Attach the elements to the cleaner body.

(3)

Attach the cleaner cover to the cleaner body.

4-

18

RECOIL STARTER

body

to the intake manifold.

Install the recoil starter to the blower housing.

6

4

X

10

mm

Do

not use the

5-

4-

19

OIL

flange bolt

bolt

FILTER

longer than

.

. .

. . .

. . . .

. .

. . . .

.

. . . .

10

mm or the flywheel fan may be damaged.

.

4

pcs.

,”

(1) Clean the oil filter

(2)

Insert the

oil

filter with the O-ring into

and

check if its mesh

Tighten the two flange bolts.

5-

4-

20

ENGINE

Fill the crankcase with

Be sure to use the diesel engine oil of proper Neve use the gasoline engine oil or the engine

OIL

oil

to the upper level

is

not broken.

the

of

grade.

may

main

the oil

bearing cover.

gauge.

be seriously damaged.

I

-

38

-

6.

GENERAL

DESCRIPTION

OF FUEL SYSTEM,

GOVERNOR

SYSTEM,

LUBRICAT ON. SYSTEM

AND

AUTOMATIC

DECOMPRESSION

6-

1

FUEL

As

DY23-2

and

DY27-2

are the high speed type diesel engine, be sure

to

use the fuel

of

good

quality automotive diesel fuel.

FUEL TANK

FUEL RETURN

FUEL INJECTION

PIPE

NOZZLE

W

U

3

m

q-ju

UU%

TIL&

w

a

m

FUEL INJECTION PUMP

U

w

3

U

FUEL

SYSTEM

CHECK

VALVE

e

fl

I

FUEL PIPE

I

FUEL FILTER

RUBBER

PIPE

1

FW

EL

PIPE

*

FILTER

-b

TANK

FUEL

NOZZLE PIPE

PUMP

INJECTION

-b

PRESSURE

-b

INJECTION

-F

FUEL

HIGH

4

L

FUEL RETURN PIPE

4

COMBUSTION

CHAMBER

FIG.

61

-

39

-

6-2

FUEL

0

FUEL INJECTION PUMP MECHANISM

It

is

not too much to say that the fuel injection pump

and

it

6

- 2 -

1

INJECTION

PUMP

is

the heart of the diesel engine,

must be precise enough to satisfy the following functions.

FUNCTION

Injecting fuel, starting with high pressure and ending with low pressure.

of

Injecting the predetermined amount

fuel accurately at each stroke. Injecting fuel at specified time within a specified time interval. Quantity being injected is closely varied by the governor to suit to varying load. This engine has no automatic advancing device, but in starting (max. delivery), the injection timing is to be delayed.

6-2-

2

THEORY

OF

THE INJECTION PUMP

MECHANISM

The plunger of the injection pump is pushed up by the cam of the camshaft, and it

is

pushed down by the plunger spring.

and forced supply

(1

)

SUCTION

OF

of

FUEL

fuel are conducted. (See Fig.

Through the filter in the fuel tank, fuel

of

port

the plunger barrel. When the top of the cam lobe passed the tappet

By

this up and down motion in a stroke, suction

62.)

is

supplied and

is

in full around the intake

and

function ended, plunger spring pushes down the plunger. When the plunger is pushed down passing the fuel intake, fuel is sucked into the barrel, and suction until arrival

of

the plunger at the. bottom

of

its

stroke. This is on the stage of

is

continued

“suction.”

(2)

FORCED

The camshaft rotates and pushes up the plunger. Forced supply only when the upper part

pushed up by the cam rotation. The fuel in the barrel force valve and the damping valve, andq then This

SUPPLY

(100

kg/cm2 and up), and as a result, the force of the fuel pushes up the delivery

is

on the stage of “pressurized supply.”

OF

FUEL

of

the plunger closed the fuel intake

is

it

injects the fuel into combustion chamber.

of

the fuel

in

the course of being

pressurized by a very strong

is

cam

I

started

VERTICAL

SUCTION PORT (DELIVELY

HOLE

PORT)

DAMPING

DELIVERY

PLUNGER

LEAD

VALVE

BARREL

FIG.

-

40

EFFECTIVE STROKE

62

-

6-2-3

VARIATION IN QUANTITY

OF

FUEL

TO

BE

INJECTED

The quantity of fuel injected varies according to the condition of the engine,

i.

e. high

speed

or

low speed operation and loaded

or

unloaded operation.

(See

Figs.

63

and

64.)

The plunger lead is engraved

on

the surface

of

plunger in an inclined curve.

By

rotating

the plunger, the distance between the upper part

of

the plunger and the suction port

is

varied. (Variation in effective stroke)

Rotation

of

the

plunger is made

by

the control rack. When this control rack

is

shifted

to

left and/or right, the geared pinion rotates, which is connected to the plunger

by

means

of

the control sleeve.

In

other words, the plunger turns as much amount as the

rack rotates. Accordingly, the effective stroke varies coincident with the position where

the rack

is

set.

(1

1

RELATION BETWEEN THE PLUNGER

AND

THE BARREL

SUCT

PLUNGER BARREL

'ION

/

DELIVERY

PORT

LEAD

PLUNGER

INJECTION INJECTION INJECTION INJECTION

STARTS. ENDS. STARTS

,

ENDS.

MAX.

DELIVERY HALF DELIVERY

NO

DELIVERY

FIG.

63

(2)

RELATION BETWEEN THE PLUNGER AND THE

RACK

NTROL SLEEVE

MAX. DELIVERY

HALF DELIVERY

FIG.

64

NO DELIVERY

-

41

-

6-

2-4

INJECTION

STARTlNG

TIMING

AND EFFECTIVE

When the plunger closes suction port the barrel, forced delivery

But fuel

is

not injected from the nozzle

at once because of contraction

of

fuel starts.

of

fuel, etc. Injection timing of this engine is fixed constant

(23"

before

TDC)

irrespective engine rpm. On the other hand, in starting, a proper delay from the timing for high speed running and increased fuel injection

is

indispensable for effective starting.

For

this

purpose a notch plunger head, which reserves injection timing by nearly starting. (See Fig.

65.)

is

made at the

to

delay the

8"

to facilitate

of

FIG.

65

6-

2-5

FUNCTION OF THE DELIVERY VALVE

By

the plunger stroke, fuel pressure is raised. And when it becomes higher than the pressure remained in the high pressure pipe, the delivery valve spring is pushed down and the valve opens. When the plunger lead meets suction port and the delivery valve is closed by the spring tension

valve prevents reverse flow of the fuel. Also suction back motion around the upper

of

the plunger sucks back the fuel in the equal amount of the stroke

As

the result, the fuel in the high pressure pipe

of

the plunger barrel, delivery

of

the valve.

is

delivered forcibly.

of

fuel ends,

At

this time, delivery

[A]

and decreases

part

remaining pressure in the high pressure pipe. The nozzle jets the fuel clearly off and prevents after dripping. (See Fig.

66.)

DELIVERY

VALVE

SPRING

,-

FIG.

-

42

66

-

BACK

STROKE

6-2-6

FUNCTION

OF

THE DAMPING

VALVE

The damping valve

is

assembled in the

end

of

injection pum-p and

it

reaches the

seat before arrival

of

delivery valve at

the seat. The small orifice in the valve

is the passage

of

fuel to the chamber in the delivery valve holder. Accordingly, descending velocity

of

the delivery valve is decreased, which prevents the negative pressure being produced suddenly.

As

a result, proper injection

is

conducted

and the engine noise is decreased.

(See Fig.

67.)

DAMPING

VALVE

DELIVERY

VALVE

FIG.

67

FUEL

INJECTION PUMP

PUMP

DELIVERY VALVE DAMPING VALVE HOLDER

HOUSIN

DAMPING VALVE

DELIVERY VALVE

PLUNGER ASSEMBLY

CONTROL RACK

CONTROL SLEEVE

SPRING SEAT

PLUNGER SPRING

SPRING SEAT

PIN TAPPET

FIG.

68

0

SPECIFICATIONS

OF

FUEL INJECTION PUMP FOR THIS DIESEL

ENGINE

Model

Right

hand

twist Lead

6

mm

Lift

5.5

mm

Plunger diameter

ZEXEL

Maker

PFRIMD55/ 2NP1

I

Plunger spring arbitrary~

I

2.21

kg/rnm

I

~~ ~ ~

Delivery valve opening pressure

1.1 kg/mm

Delivery valve spring constant

Approx

1

5

kg/ cm*

~~ ~~ ~~~~ ~~~ ~

I

Rack stroke

I

10mm

I

-

43

-

6-3

6-

3-

FUEL

1

INJECTION

SPECIFICATfONS

NOZZLE

I

Part Name Type

No.

Valve opening pressure Spring constant

No.

of

nozzle hole

(Diameter)

NOZZLE ASSEMBLY

DLLA150PN52

4

(0.22

mm)

195

kg/

ern'

13.2

kg/ mm

I

6-

3-

2

FEATURES

Both the injection nozzle and the injection pump are very important fuel mist the other

combustion. There are two types

is

pintle type.

of

injection nozzle, one is hole type

for

The injection nozzle for DY23 and DY27 Diesel engines is developed as a result of joint research and development project by Diesel Kiki and our company, and it combustion system, having the special hole type nozzle. For producing better air-fuel mixture, fuel mist most effectively, injection pressure

it

utilizes

is

swirl

raised

and squish

up

to 195 kg/cm2.

parts

flows

for producing

and

is

direct

and deliver the

/-

6-3-3 STRUCTURE

NOZZLE

OF

THE INJECTION

ASSEMBLY

The injection nozzle assembly consists

of nozzle holder and nozzle. The nozzle

holder fixes the nozzle to the cylinder head and at the same time it plays the role of fuel passage to the nozzle.

The nozzle consists

of

the nozzle body and needle valve. When the fuel pressure reaches up to the valve opening pressure, the needle valve

is

raised up and the fuel

through the small holes at the

is

tip

injected

of the

nozzle body. .The valve opening pressure is adjustable

by changing the adjusting washers.

IDENTIFICATION

NOZZLE

VALVE CLOSED VALVE OPENED

MARK

SPRING

ADJUSTING WASHER

FIG.

69

NOZZLE

BODY

FIG.

70

-

44

-

6-3-4

FUEL

PASSAGE

From the plunger pump fuel is sent through the high pressure pipe

1

to the

fuel passage

2.

Then, at the nozzle body

3,

it is pressurized up till

195

kg/c

m’

and

it

lifts up the needle valve 4 for

0.18

mm, and is injected into the combustion chamber via the jet hole

5.

An excess fuel which lubricated the inside of the nozzle and nozzle holder returns to the fuel tank via the needle valve-, nozzle spring

6

-overflow pipe

7

+-fuel

tank. (See Fig.

7

1

.>

a

7

3

4

5

FIG.

71

6-

3-

5

INSPECTION

AND

MAINTENANCE

Fuel injecting condition of the nozzle and the valve opening pressure are quite influential to the engine operation, insufficient output, increase

of

noise and exhaust smoke. Use of

improper fuel

or

contaminated fuel is one of the main causes of the nozzle trouble.

Therefore, exert good care for using good fuel.

As

the nozzle is assembled from very

precisely finished parts, utmost care and attention must

be

paid when inspecting and

checking.

(1

)

INSPECTION

After cleaning nozzle holder outside, inspect in the following steps

:

a) Visual inspection

Whether

or

not injection hole

is

damaged, or clogged with carbon. Whether

or

not injection hole is clogged

with dust and carbon.

b) Checking by nozzle tester

Fit the nozzle assy to the nozzle tester.

When removing

the

nozzle

~~QPVI

the

engine

or

fitting, it to tester, be sure

to

.keep

the

nozzle

free

of

dust.

FIG.

72

Move the lever

of

the nozzle tester up

and down for

2-3

times and

suck

the

air inside the nozzle.

Newer bring

your

face

near

the injected

fuel mist

from

the

nozzle.

Also

keep

away

your

hands

from the mist.

-

45

-

@Gently push down the lever

of

the nozzle

tester and read the pressure gauge just before the fuel being injected. If the figure coincides with the standard value, the nozzle

in a

good

condition.

is

@Push further and check whether or not

the fuel mist

Good Just after injection, check “after

dripping.”

(2)

If

the test results are found not good (poor

injection

MAINTENANCE

is

injected straight.

is

straight forward.

injection and “after dripping”), carefully check and repair in the following procedure

:

NOZZLE

FIG.

73

a) Disassemble the nozzle holder and nozzle,

and wash in clean light oil.

a

When washing, use

(for instance, wooden toothpick

wooden chip

is serviceable.) for peeling off the carbon adhered to the nozzle.

b)

After washing, pull out the needle

halfway your fingers and then let it

check

dead weight.

c)

If

it

from

if

the needle

the body of nozzle with

does not sink, replace

sinks

by

it

go.

its

in

And own

the

FIG.

74

form of a set.

d) Frinction surfaces of both the needle and

nozzle body are ultra precise finish.

sure to keep the parts free of dust.

e>

If

“after dripping“

In

such a case, it

body. However, it

is

advisable

is

possible

found,

it

is

poor

to

replace

to

coat chrome oxide

contact between the needle valve

it

in the form of a set, needle valve and nozzle

on

the tapered surface of the needle

and get a good contact. Wash very carefully after correction.

f>

The spacer body. Pay attention

g)

When fitting the nozzle body to the nozzle holder, conform

is

an important part to set positions of the nozzle holder

to

the position of the pin.

to

the specified tightening

toruqe.

Tightening torque

h)

Recheck with the nozzle tester. If the adjustment of valve opening pressure necessary, adjust it to The valve opening pressure shall decrease to

:

300-400

200-210

kg-

kg/c

cm

m‘.

195

kg/c

mz

after the running in.

NEEDLE

.

BODY

and

So,

be

the seat.

the nozzle

is

,

-

46

-

6-4

GOVERNOR MECHANISM

AND

OPERATION

6

-

4-

I

MECHANISM

The governor

is

centrifugal flyweight type, which means

a

flyweight is fitted to

the

governor

gear.

The governor sleeve is assembled

so

that it may slide toward the direction

of

the axis of the pump shaft, and it

is

in

contact with the flyweight. The governor sleeve gets in touch with the governor yoke, and through the governor lever it makes the

control

rack of injection pump operate. This mechanism enables to maintain constant

operation irrespective

of

load variation.

\

SMOKE

SET

SMOKE

SET

SPRING

Operation when load

is

applied

or

starting.

+

Operation when load is decreased

or

removed.

4

FIG.

75

-

47

-

6-

4-

2

OPERATION

1.

STARTING

When the speed control lever is set to the high speed (start) position, the governor lever is pulled by the governor spring through the control link. The control link compress the smoke set spring at the same time to allow the injection pump to deliver extra fuel for starting.

2.

OPERATION

UNDER

LOAD

When the engine starts up, the flyweights expand by the centrifugal force pushing the governor sleeve. The governor lever pushed by the governor sleeve moves

to

the control rack of the fuel injection pump in the direction of reducing fuel. Thus, the engine speed rises up to the predetermined level, and maintains this speed where the centrifugal force balances with the tension of the governor spring. When a load is applied to the engine, the engine reduces

At

this moment, as the centrifugal force

at

the flyweights is weakened, the governor

its

speed

for

a moment.

lever being pulled by the governor spring moves to push the control rack of the fuel injection pump in the direction of increasing fuel. Thus, the engine recovers its speed

or

to the predetermined level. When the load is reduced

removed, the governor’ system

operates exactly in reverse to maintain the engine speed.

When the engine is over-loaded, the control link touches the smoke set. However, the

tension of the governor spring is weaker than the combined force of the centrifugal

force

of

the flyweights and the smoke set spring, the governor iever can not move

further to increase fuel. Under this condition, the engine speed is reduced and the

engine exhausts black smoke.

3.

STOPPING

By

pushing the stop lever, the governor lever pushes the control rack

pump all the way

to

“fuel shut off” position to

stop

the engine.

of

the injection

/-

push

/-

6-5

LUBRICATION

Forced lubrication system is adopted to pump

is

mounted on the .main bearing cover co- axialy with the governor gear and is

SYSTEM

AND

OIL

PUMP

DY23

and

DY27

engines. The trochoid type oil

driven by the cam gear. The

oil

in the oil pan

is

filtered by the oil filter and is forcibly delivered by the oil pump to the crank jounal and then to the crank pin lubricating the main bearing and the large end bearing. The oil splashes from the crank journal and the crank pin

to

lubricate cylinder wall, piston, small end, cam shaft and the governor system. The rocker arms, valve system etc. inside of the rocker chamber are lubricated by the oil mist contained in the blow

-by gas supplied from crankcase. The blow- by gas enters into the combustion chamber through the breather valve, and

the

oil

contained in the blow-

by

gas

is

finally burnt out.

-

48

-

FORCED LUBRICATION

BY

OIL

PUMP

*

LUBRICATION

BY

SPLASH

111,

1

LUBRICATION

SYSTEM

FIG. 76

0

OIL FILTER

Oil

filter

is

made

of

nylon mesh

and

is

reusable after cleaning.

As

the oil flows from the inside

of

the filter

to

the outside, be sure to clean the inside thoroughly. Clean the oil filter every time

of

oil

change.

-

49

-

6-

6

AUTOMATIC DECOMPRESSION

The decompression system operates to release compression by lifting up the exhaust valve at starting. The release lever mounted on the camshaft has a flyweight at one end and a crescent cam exhaust The exhaust tappet rides compression.

at

the other end. When starting the engine, the crescent cam juts out from the

.

cam.

over

the crescent cam opening the exhaust valve to release

SYSTEM

,”

TAPPET

FLYWEIGHT

CRESCENT

EXHAUST

When the crank moves outward by the centrifugal force turning the release lever to retract the crescent cam. Thus the exhaust valve closes allowing a sufficient compression for the engine to start up.

CAM

speed

reaches

EXHAUST CAM

FIG.

a

certain revolution, the flyweight

2LtL

/

77

l/

of

RELEASE LEVER

SNAP RING

CAMSHAFT

the release lever

,--

‘FLYWEIGHT

FIG.

78

The components engines, however the principle of operation is the same.

of

the decompression system are different by

“D”

LEASE LEVER

type and

SNAP RING

CAMSHAFT

“B”

type

/

-

50

-

7.

STARTING

SYSTEM

-

7-

1

RECOIL

The recoil starter hardly has a trouble in the normal use, .however, in case it has a trouble

following procedures Tools to be used

The following explanation is applicable to the recoil starter for For

7-1

(1)

(2)

or

“B”

type models, reverse the direction

-

1

HOW

Remove the recoil starter engine with a

Pull the starting knob and pull out the starter rope press the reel with a thumb as shown in Fig. make reverse turn at the place where the reel notch comes to the outlet starter rope. Pull out the starter rope to the inside of recoil starter with a screwdriver.

Then, utilize the reel notch, and rewind it until the rotation stops in the arrowhead direction, braking the reel rotation with a thumb.

STARTER

at the time

:

Box

TO

DISASSEMBLE

box

for

79

so

that the reel should not

of

lubrication, perform disassembly and reassembly in the

spanner (spanner), Cutting pliers (pliers) and Screw driver

“D”

spanner.

30

to

(D

from

40

cm. Firmly

Type)

the

of

rotation to achieve proper service

STARTER

ROPE

type

engines.

of

/q

STARTER

FIG.

NKOB

79

work.

(3)

When removing, take out the parts

of

in the order

80.

1.

“U”

type snap ring

2.

Thrust washer

3.

Friction spring cover

4.

Return spring

5.

Friction spring

6.

Ratchet

I

Meantime, snap ring, nip the shaft with cutting

pliers and push

for

the numbering in Fig.

removing the

it

out.

“U”

type

2

FIG.

80

-

51

-

(4)

Take out the reel from starter case as shown in Fig.

81.

In this case, slowly take out it turning the reel lightly toward left and right

so

that the spring is removed from

the reel hook section.

If the

reel

is suddenly taken out, there is a fear that the spring jumps out in the very dangerous,

form

as

it

is

hooked, which

so

be careful1 of it. (If the spring jumped out, house it in the starter case as instructed in Fig. Finally, release and take out the starter rope tied to both the reel side and the starting knob side. Thus, the disassembly

work

ends.

is

86.)

REEL

STARTER CASE SPRING

FIG.

81

INO.

2

I

7-

1-2

HOW

(1)

First, have the starter rope pass

TO

REASSEMBLE

(D

through the starting knob, and tie the

82

rope as shown in Fig.

No.

Then, have the opposite side of the rope pass through the starter case and

it

the reel, and tie

82

No.2.

Then surely house the end

as shown in Fig.

in the reel. (In the Fig.82 both the ropes are tied quite lightly, as you see in figures

No.1

and

No.2.

note this is just for the purpose easy understanding. Therefore, when actually tying, tie the rope as tightely

as possible.

(2)

Confirm that the spring is surely set

in the starter case housing section, and have the spring to form inner end will the starter shaft and that

be

about 3mm

so

it

surely the reel hook. Meantime, with the pliers about 10 cm long spring from the inner end can easily be formed.

Type)

1.

Please

that

from

hooks

of

its

STAR1

OUTER END

'ER

SHAFT

FIG.

OF

11

82

SPRING

INNER END

REEL

/

OF

HOOK

/

SPRING

-

52

FIG.

83

-

Before putting the reel in the starter case, wind the starter rope in the arrowhead direction as shown in Fig.

84,

and at

2.5

windings take out the rope from the reel notch. Set the reel hook to the inner end of the spring,

and put the reel in the starter case.

(At

this time, confirm that the reel

hook

is duly set to the spring.) Then, hold the starter rope as shown in Fig.

84,

and turn the reel

4

times in the arrowhead direction. When wound up, firmly press the reel not to allow reverse turn, and pull the starting knob. Then, pull out from the starter case the starter rope utilized for winding, and slowly return the starting knob.

When reassembling the parts, follow up in the reverse order to Fig.

80.

When putting the friction plate in the hole for it, set the return spring a little upward as shown in Fig.

85

so

that

the friction plate can easily be put

in the hole for it. Next, turn the friction plate in the arrowhead direction till the position where its notch matches with the ratchet. Push firmly the friction plate to

the reel side, and put the thrust

washer and then clamp it with a

“U”

type snap ring.

(Use pliers to set the snap ring

securely.)

*

FIG.

84

CH

FIG.

85

.This is the end

of

the disassembly and reassembly procedures.

Test the reassembled recoil starter by the following checking procedures in the next page.

-

53

-

7-

1

-

3

CHECKING PROCEDURES AFTER REASSEMBLY

(1)

Pull the starting knob

a)

If

the starting knob is felt heavy to pull or cannot be pulled, check whether all the

2

or 3 times, and pull out the starter rope a little.

(D

Type)

parts are installed correctly.

b)

If

the ratchet does not function, check whether the spring is hooked properly.

(2)

Pull the starting knob, and pull out the starter rope all the way long.

a)

If

the starter rope remains left in the reel

all, immoderate strain

b)

times

If

as

per instruction in Fig.79.

the return power of the starter rope is weak

is

imposed on the spring.

or

the starter rope does not return at

So

rewind the starter rope

or

the starter rope cannot be fully

rewind, inject a few drops of mobile oil in the frictional portions. If it does not

1

or

2

recover yet, wind the rope

(In this case, refer

confirm whether

c)

If

the sound is heard that the spring

or

not immoderate strain

to

the instructions explained in the paragraph a) above and

times.

is

imposed on the spring.)

falling off, and the starter rope cannot be

wound in relay, reassemble once again from the biginning.

1

or

2

7-

1-4

USEFUL

(1

)

IN

CASE

DISASSEMBLING

REMINDERS

THE

SPRING

JUMPS OUT WHEN

With thin wire make a ring smaller than the case for spring, and hook the outer end of spring

on

the part

of the ring as shown in Fig. 86. Store

it

in the spring housing section the reel, and carefully remove the ring, pressing the spring with fingers as not to come out. The ring can easily be removed

tip

of the screwdriver

Refer to Fig.83 for

squeezing

not

it with the

or

the like.

to

by

the direction of the spring.

(2)

LUBRICATE RECOIL

COMPONENTS

Lubricate the rotating parts, frictional parts and spring with heat resistant grease, disassembly

or

mobile

or

oil

at the time

at

the end of season

for use.

of

so

mistake

of

FIG.

86

,

-

54

-

7-2

7

-

2

-

ELECTRIC

1

SPECIFICATIONS

STARTING

MOTOR

(OPTIONAL

PART)

Part

Name

Maker

Output

Weight

Starting

Nihon

Denso

0.6

kW

3.0

kg

Motor

K.

DRIVE

PIS1

DRIVE LEVER

STOP

MAGNET

DRIVE

COLLER

SPRING

BOLT

SWITCH

\

BRUSH

FRAME

7-2-2

WIRING

DIAGRAM

LIGHT

BLUE LIGHT

BLUE

FIG.

87

KEY

r----

SWITCH

RED

IC

I

Connect positive

switch

treminal.

(+)

battery terminal to 8 rnm magnetic

FIG.

88

-

55

I

L------J

BATTERY

12V-24AH

~

-

8.

PRECAUTIONS

EQUIPMENT

FOR

MOUNTING

THE

ENGINE

ON

THE

The installation of an engine to the equipment effects greatly to the ease

8-

1

INSTALLATION

When designing the equipment, pay a sufficient attention to the mounting position, coupling methode with the equipment, base and supports.

8

-

2

VENTILATION

Engine requires a sufficient amount of clean and fresh air for. combustion of fuel and cooling. If the engine is covered with an enclosure, the engine may overheats unless outside of the engine room.

High surrounding temperature also causes the deterioration of engine oil, increased oil consumption, lower output, and piston seizure resulting in the shorter engine life. Therefore, it is necessary to provide a duct or a baffle to the engine to prevent recirculation

A

prudential attention have to be paid to keep the engine room temperature below

(122"

F).

or

reflection

of

a

sufficient amount of fresh air

hot cooling air.

or

the engine is operated in a small room,

is

of

maintenance.

supplied from the

50°C

8-3

EXHAUST

Exhaust

engine indoors

If

an exhaust pipe extension is used to discharge exhaust gas, be careful of the inner

diameter of the pipe to prevent power loss.

Recommendation of exhaust pipe extension

8-4

If

the fuel tank is separately mounted on the equipment from the engine, be sure to

set the bottom

If

the tank When piping the engine, be carefuI the joints and make the fuel pipe as short as possible being trapped.

gas

Less than 3 m long : inner diameter Less than

FUEL

GAS

is

noxious. Be sure to discharge exhaust gas outdoors when operating the

or

in a poorly ventilated area such

:

35

mm.

5

m

long : inner diameter

SYSTEM

of

fuel tank not less than

is

mounted too low, the fuel may not be supplied properly to the engine.

of

38

mm.

50

mm higher than the fuel injection pump.

heat conduction, pipe size, bends, and leaks from

as

in a cave, tunnel, etc.

to

prevent air and vapor from

/

-

56

-

8-5

POWER TRANSMISSION TO

DRIVEN

MACHINES

8-5-

1

BELT

DRIVE

Take the following notes into consideration.

(1)

V-belts are preferable to flat belts.

(2)

The driving shaft of the engine must be parallel

(3)

The driving pulley

of

the engine must be in line with the driven pulley

to

the driven shaft of the equipment.

of

the

equipment.

(4)

Install the driving pulley as close to the engine as possible.

(5)

Span the belt horizontally

(6)

Disengage the load

If

8-

the clutch

5-

2

FLEXIBLE

is

COUPLING

at

not adaptable, use a belt tensioner

if

possible.

starting the engine.

or

the like

to

disengage load.

When using a flexible coupling, minimize the runout and misalignment between the engine shaft and the driven shaft. The allowance are specified by the coupling maker.

-

57

-

9.

CHECKS

After disassembling and cleaning the engine, check and repair, if necessary, according to the correction table. The correction table applies whenever the engines are repaired.

It is important for the servicemen to Correct maintenance is recornrnendk The meanings

(1 1 CORRECTION

Repair, adjustment

(2

1

CORRECTION LIMIT

The limit on wear, damage normal engine performance cannot be expected without repairing such parts.

(3)

USE

The limit beyond which parts can strength.

(4)

STANDARD DIMENSIONS

The design dimensions of new parts minus tolerance.

(5)

Tolerance

LIMIT

CORRECTION TOLERANCE

AND

of

the terms used in the correction table are as follows

on

the dimensions

CORRECTIONS

be

familiar with the contents

by

observing the correction standards specified.

or

replacement of any engine parts.

or

functional deterioration of engine parts beyond which

no

longer

of

engine parts refinished

be

used

in respect of performance

or

of

adjusted.

this table.

:

or

9-1

Engine

SERVICE DATA

CYLINDER

@

Flatness

@Valve seat contact width

HEAD

(@)

eValve

guide

inside

ITEM

dia.

Unit

:

mm

(in)

STD

DY23

Limit

DY27

I/

I

0.05

(0.002)

1.6

(0.063)

5.5-5.518 5.65

0.05

(0.002)

2.2

(0.087)

I

(0.21 65-0.21 72) (0.2224)

-

58

-

Unit

:

rnm

(in)

ITEM

CYLINDER

@Inside

dia.

PISTON OPiston size (At skirt,

thrust direction)

I

Ring groove side

clearance

in

I

1st

2nd

1

STD

o/s

DY23

70.000-70.01 9 70.25

(2.7559-2.7567) (2.7657)

69.961 -69.981

(2.7544-2.7552)

70.21 1-70.231

(2.7642-2.7650)

o/s

70.461 -70.481

(2.7741 -2.7748)

0.05-0.09

(0.0020-0.0035)

69.871

(2.7508)

70.1 21

(2.7607)

70.371

(2.7705)

0.1 5

(0.0059)

DI

STD

75.000-75.01

(2.9528-2.9535)

74.961 -74.981

(2.9512-2.9520)

75.21 1-75.231

(2.961 1-2.961 9)

75.461 -75.481

(2.9709-2.9717)

0.05-0.09

(0.0020-0.0035)

9

27

Limit

75.25

(2.9626)

74.07

1

(2.9477

75.1 21

(2.9575)

75.371

(2.9674)

0.1 5

(0.0059)

Piston

OPiston

@Clearance between piston

and cylinder at skirt area.

0

Piston ring end gap

hole

f

outside dia.

f

0.01 5-0.055

(0.0006-0.0022)

18.001

(0.7087-0.7090) (0.7098)

r

1-

18.000- 18.006 17.980

(0.7087-0.7089) (0.7079)

0.01 9-0.058 0.1 5

(0.0007-0.0022) (0.0059)

I

To

P

0.3-0.5 1

(0.0039)

-

18.008 18.03

0.1

.o

0.015-0.055

(0.0006-0.0022)

18.001 -18.008

(0.7087-0.7090)

18.000-1 8.006

(0.7087-0.7089)

0.019-0.058

(0.0007-0.0022)

0.1 -0.3

0.1

(0.0039)

18.03

(0.7098)

17.980

(0.7079)

0.2

(0.0079)

0.8

2nd

Oil

(0.01 18-0.01 97) (0.0394)

1

0.25-0.45

(0.0098-0.0177) (0.0394)

-

59

-

.o

(0.0039-0.01 18)

0.25-0.45

(0.0098-0.01 77)

(0.031

5)

1

.o

(0.0394)

Unit

:

mm

(in)

CONNECTING

.Big end inside dia.

(Metal is fitted)

.Clearance between

big

end and crankpin

Small end inside dia.

OClearance between small end

and piston

ROD

ITEM

STD

33.050-33.090

(1.301 2- 1.3028)

0.023-0.081

(0.0009-0.0032)

18.01

3-

18.034

(0.7092-0.7100)

0.007-0.034

DY23/DY27

Limit

33.2

(1.3071

0.1

(0.0039)

18.05

(0.71

06)

0.08

)

0

Big

end side clearance

CRANKSHAFT

0

Crankpin outside dia.

0

Journal dia.

I

A

8

(0.0003-0.0013)

0.10-0.30

(0.0039-0.01 18)

33.01 1-33.027

(1.2996-1.3003)

32.984-33.000

(1.2986-1.2992)

(0.0031

0.5

(0.01 97)

32.85

(1.2933)

32.85

(1.2933)

)

OClealance between

journal and main bearing

I

-

60

-

0.014-0.oa6

(0.0006-0.0034)

0.1 2

(0.0047)

Unit

:

rnm

(in)

CAMSHAFT

0

Cam

height

0

.Journal outside dia.

"D'

type

ITEM

IN.

EX.

cams

Injection

pump

cam

Flywheel

side

R1

PTO

side

R2

STD

32.1 3-32.23

(1

2650- 1.2689)

29.95-30.05

(1.1791-1.1831)

24.934-24.947

(0.981 7-0.9822)

14.973- 14.984

(0.5895-0.5899)

DY23/DY27

Limit

31.98

(1.2591

29.85

(1.1

752)

24.90

(0.9803)

14.90

(0.5866)

VALVE

.Valve stem outside dia.

.Clearance between valve

stem dia. and valve guide

0

Valve clearance

IN.

EX.

IN.

EX.

5.422-5.437

(0.21 35-0.2141

5.402-5.417

(0.21 27-0.21 33)

0.063-0.096

(0.0025-0.0038)

0.083-0.1 16

(0.0033-0.0046)

5.35

)

(0.21 06)

5.35

(0.21

06)

0.3

(0.01

18)

0.3

(0.01

18)

IN./

(cold)

EX.

-61

0.07-0.1

Adjustable

(U.OO28-U.OU39)

-

Unit : mm

(in)

TAPPET

0

Stem outside dia.

0

Guide inside dia.

0

Tappet

guide

clearance

ITEM

Q

r

(0.3134-0.3140)

(0.31 50-0.31 56)

DY23/DY27

STD

7.960-7.975

8.000-8.01

0.025-0.055

(0.001 0-0.0022)

5

Limit

7.93

(0.3122)

8.08

(0.31

8)

0.1

5

(0.0059)

,

ROCKER ARM

0

Rocker shaft outside dia.

0

Rocker arm

@Rocker arm shaft clearance

VALVE

SPRING FREE LENGTH

hole

dia.

11.937-1 1.984

(0.4714-0.4718)

12.000-12.01

(0.4724-0.4731

0.01 6-0.045

(0.0006-0.0018)

11.92

(0.4693)

8

)

12.07

(0.4752)

0.1

5

(0.0059)

-

62

.O

32.5

(1.2795)

31

(1.2205

1

-

Unit

:

mrn

(in)

ITEM

INJECTION

From injection pump flange surface

e

Static injection timing

NOZZLE

0

Injection starting pressure Nozzle dia./ Number

ENGINE COMPRESSION

(at

400

VALVE .Valve cutter angle (a) .Valve contact width

PUMP

r.

P.

m.

SEAT

of

by

hand)

ANGLE (IN. EX.)

(b)

nozzle

to

cam base

I

DY23

DY27

STD

65.95-66.05

(2.5965-2.6004)

21

-23

ETDC

195

kg

/

cmz

(2773

Ibj

in2)

0.22

(0.009)

18

(256.0

17- 17.5 kg/

(241.6-248.9 Ib/

/4PCS.

kg/cm2

Ib/

in2)

cmz

DY23/DY27

I

in2)

Limit

Adjustable

13

kg/ cmz

(1

84.9

Ib/

12

kg/

(1

70.7

Ib/

in2)

cmz

in2)

b

:

2.2

mm

(0.0866

Description

a

TABLE

OF

TIGHTENING

b

:

1.6

mrn

(0.0630

TORQUE

in)

I

Tightening Torque

Bolts for joining main bearing cover 170-1 90 kg- cm (1 2.3-1 3.7 ft Ib)

Nuts

for

joining cylinder head

Bolts for joining connecting rod cap Flywheel nut

DY23 DY 27

300-330 kg- cm (21.7-23.9 ft Ib)

ft

=

Ib)

Ib) Ib)

330-350 kg-cm (23.9-25.3 ft 180-200 kg-cm (13.0-14.5 ft 600-650 kg- cm (43.4-47.0

in)

Oil

drain plug

Nuts for joining injection nozzle

-

63

-

200-230

50-60

kg-

cm

(14.5-1

6.6

ft

0

kg- cm (3.6-4.3 ft * Ib)

Ib)

IO.

MAINTENANCE AND

STORI

The following maintenance schedule applies to the engines operated correctly under normal conditions.

The indicated maintenance schedule does not necessarily guarantee maintenanceoperations during the intervals.

For

example, if the engine is operated in extremely dusty condition, the air cleaner should

of

be cleaned every day instead

10-

1

DAILY

Checks and maintenance works

Remove dust, dirt, debris, grass and any foreign obstacles from cylinder, cylinder head, carburetor and governor system.

Check fuel leakage. the loose joint and/or replace leaking part.

CHECKS

If

leakage is found, tighten

AND

MAINTENANCE

every

50

hours.

Reasons for requiring the maintenance work

(1)

Engine overheats.

(2)

Engine does not operate properly.

of

Danger

fire.

,

free

Check bolts and Tighten the loose bolt and/or nut

Check oil level and fill up as necessary.

10-

2

INITIAL

Checks and maintenance

Change engine oil.

nuts

25

for looseness.

HOURS

CHECK

works

if

AND

Engine malfunctions causing damages

any.

engine and/or the equipment.

Insufficient oil causes engine seizure.

MAINTENANCE

Reasons

To

I

for

requiring the maintenance work

remove break- in dregs.

to

the

,

I

-

64

-

2.

10-3

EVERY

100

HOURS

(MONTHLY)

CHECKS AND MAINTENANCE

Checks and maintenance works

Change engine

Clean oil filter.

Clean air cleaner.

Check battery electrolyte level.

Discharge water from fuel filter.

10-

4

EVERY

oil.

500

HOURS

CHECKS AND

Reasons for requiring the maintenance work

Contaminated oil accelerates wear.

oil

Insufficient

Clogged operation.

Insufficient electrolyte lowers battery performance and shorten battery life.

Water in the fuel causes poor engine

operation, bad starting and corrosion injection

MAINTENANCE

air

pump

causes engine failure.

cleaner causes poor engine

in

and nozzle.

the

Checks and maintenance works

Check

I

Remove carbon deposit from cylinder head.

10-

and

5

EVERY

adjust valve clearance.

clean injection nozzle.

1000

HOURS (YEARLY)

I

Checks and maintenance works

I

Replace piston rings.

Replace fuel lines.

Reasons

I

Improper valve clearance output.

Poor operation

Poor operation of the engine.

CHECKS

I

Reasons

I

Poor performance

To

for

requiring the maintenance

of

the

engine.

AND MAINTENANCE

for

requiring the maintenance

of

the engine.

prevent from fuel leaking.

causes

poor

work

engine

I

work

1

Replace fuel filter

Check valve seats Grind valve seats

both

if

intake and exhaust.

necessary.

Poor operation

-

65

-

of

the engine.

of

the engine.

Check

Overhaul the

IO

-

7'

PREPAWATIO

(1)

Perform the above maintenance works 10 Also perform 10

(2)

Drain fuel

(3)

To

protect cylinder bore from rusting, pour a small amount

through the auxiliary fuel inlet into the cylinder and pull the recoil starter slowly

2

to 3 times.

and maintenance works

engine.

S

from

FOR

-

5

and 10

the tank.

(Do

not start the engine.)

LON6

-

6

Reasons

To

engine

STORAGE

as necessary.

recover

life.

-

1

through 10

for requiring the maintenance work

the engine power

-

4.

(4-5

and

extend

cc) of engine

oil

Bo

not

pour too

1

top.

(4)

Pull the recoil starter slowly and stop it at the compression point.

(5)

Clean the engine outside with

(6)

Put a cover over the engine and store it in

much

oil

or

the

oil

rernaines in

a

oily cloth.

the

combustion chamber

a

dry and well ventilated area.

of

the

piston

,

-

66

-

Industrial

Engines

Robin DY23, DY27 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual