Robin EY14, EY23, EY18-3, EY25-2, EY27-2 Service Manual

ROBIN

ENGINE

ROBIN

MODEL CROSS

AMERICA,

TO

WISCONSIN

mc.

ROBIN

REFERENCE

LIST

ROBIN

EY08 EYl5

15V

EY

EY20

EY2OV EY23 EY28 EY35 EY40 EY45V

1

EY2 EY44 EY 18-3

EY25

EY27

-

WISCONSIN

W1-080 W1-145 W1-145V w1-185

W1-185V

Wl-230

W

1-280

W1-340

W1-390

W1-450V EY21W EY44W

18-3W

EY

EY25W

EY27W

ROBIN

EHl 1

EH12

EH15

EH17

EH21 EH25 EH30 EH3OV EH34 EH34V EH43V

EC13V

DY23

DY27

DY30 DY35

DY4

1

TWO

CYCLE

WOl-115 WOl-120 WO1-150 WO1-170 wo1-210 WO1-250

WO

1-300

WO

1

-300v

WO

1-340

WO

1 -340V

WO

1 -430V

WT1-125V

WRD

WRD WRD

WRD1-350

wRDl-410

1-230 1-270 1-300

CONTENTS

Section Title Page

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

1

.

SPECIFICATIONS

1

2

.

PERFORMANCE

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

2

2-1 Maximum Output

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

2

2-2 Continuous Rated Output

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

2

2-3

Maximum Torque and Fuel Consumption Ratio

at

Max . Output

.........

2

3

.

FEATURES

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

4

.

GENERAL DESCRIPTION

of

ENGINE CONSTRUCTION

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

4

4-1

Cylinder Crankcase

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

4

4-2 Main Bearing Cover

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

4

4-3 Crankshaft

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

4

4-5 Camshaft

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

4

4-7 Cylinder Head

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

5

4-8 Governor

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

5

4-9 Cooling

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

5

4-10

Lubrication

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

5

4-11 Ignition

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

5

4-13 Air Cleaner

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

5

4-14 Sectional View

of

Engine

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

6

4.4 Connecting Rod and Piston

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

4

4-6 Valve Arrangement

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

5

4-12 Carburetor

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

5

5.lNSTALLATlON

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

14

5-1 Installing

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

14

5-2 Ventilation

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

14

5-3 Exhaust Gas Evacuation

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

14

5-4

Fuel System

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

14

5-5 Power Transmission to Driven Machines

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

14

5-6

Wiring

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

15

6

.

DISASSEMBLY

and

REASSEMBLY

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

21

6-1 Preparation and Suggestions

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

21

6-2 Special Tools

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

21

6-3

Disassembly and Ressembly Procedures

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

22

7.MAGNETO

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

29

7-1 Magneto

7-2

Breaker Point Adjustment

7-3

Timing

74 Magneto Trouble Shooting

8

.

GOVERNOR ADJUSTMENT

9.

CARBURETOR

9-1

Operation and Construction

9-2

Disassembly

9-3 Adjustment

10

.

RUN-IN OPERATION

11

.

TROUBLE SHOOTtNG

11

-1 Starting Difficulties

11

-2

Engine Misses

11-3

Engine Stops

114

Engine Overheats

11-5

Engine Knocks

11-6 Engine Backfires Through Carburetor

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

Adjustment

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

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

and

Reassembly

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

of

REASSEMBLED ENGINE

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

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

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

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

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

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

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

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

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

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

29 29

30

31

32

33

34

36

37

38

38 39 39 39

40

12

.

CHECKS AND CORRECTIONS

13 . CORRECTION TABLE

14

.

MAINTENANCE

14-1 Daily Checks and maintenance (Every 8 Hours)

14-2

Every

14-3 Every

14-4

Every 14-5 Every 500 14-6 Every 1000 Hours (Yearly) Checks

14-7

Preparation for Long-Term Storage

20

50

100

and

Hours

. .

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

STORING

Checks and Maintenance

(10

Day)

200 Hours (Monthly) Checks 600 Hours (Semianual) Checks and Maintenance

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

Checks and Maintenance

and

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

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

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

and

Maintenance

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

...........

Maintenance

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

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

41

42

48

48 48 49 49

49

1.

SPEC1

FICATIONS

[

N

m

p

52

0

n

0"

V

t

1

c

t

I

i

-1

-

2.

PERFORMANCE

2-1

MAXIMUM OUTPUT

n

The Maximum output of an engine is initial run-in period with

all

the

open throttle valve. Therefore, it

the

output in

2-2

CONTINUOUS RATED OUTPUT

The continuous running

beginning, because moving parts are not in a properly worn-in condition.

rated

at

an optimum speed most favorable from the point of view of engine life and fuel

output of an engine

consumption ratio. Therefore, it follows that when designing

such

standard power

as

developed

by

that engine,

moving parts properly worn-in, when operating with the fully

follows

that

is

such

a

new engine may not develop this maximum

power as developed

a

by

driving system for any

mechanism, with a model EY14, EY18-3, EY23, EY25-2 and EY27-2 engine,

the

continuous power requirement of

that

mechanism must

be

kept below

the

output specified.

2-3

MAXIMUM TORQUE

The maximum torque of an engine is

is

driving an external load,

consumption ratio

is

running

at

the

PERFORMANCE CURVE

at

rnax. output.

and

FUEL CONSUMPTION RATIO

while

max. output

is

AT

MAX. OUTPUT

that

driving torque of the driving shaft

the

engine

that

fuel consumption ratio

is

developing

its

of

PERFORMANCE CURVE

MODEL EY18-38

max. output. The fuel

an engine while

after

that

engine when

as

a

prime

mover,

continuous

at

which the engine

that

engine

its

rated

-2-

PERFORMANCE

CURVE

MODEL

EY23

7

( )

for

B

type

1.5(3.0)

1.0

(2.0)

6

I

5

kg-m

HP

I4

3

I

g1HP.h

3

50

2

300

250

2000

3000

4000

(1

000)

(1

500)

(2000)

rpm

__c

PERFORMANCE CURVE

MODEL EY25-2

(

)

for

B

type

.h

PERFORMANCE CURVE

MODEL EY27-2

(

)

for

8

type

1.4(2.8)

1.3(2.6)

7

I

kg-m

6

5

HP

I4

3

I

g1HP.h

340

2

320

2500

3000

3500

4000

(1250)

(1500)

(1750)

(2000)

rpm

-

-3

-

FEATURES

A

compact, lightweight and durable 4-cycle air-cooled engine with high power output,

embodying ingenious design technique and advanced production skill.

n

Simple construction, smart appearance, easy

start.

Reliable power for wide. variety of purposes, with smooth speed controll by

a

governor,

under varying

load

conditions. Economical advantage through low fuel consumption. Great versatility in installation through

a

360°

belt

extension possibility and a two side

oil

fill and drain arrangement.

GENERAL DESCRIPTJON

of

ENGINE CONSTRUCTION

CYLINDER, CRANKCASE

The

cylinder and

the

crankcase

are

die-cast

as

a

compact aluminium mono-block piece.

The

cylinder liner and

the

valve

seats

are

made of special alloy

cast

iron and

are

imbedded in

the

aluminium casting

as

inserts. The intake and exhaust ports

are

located

at

one side

of

the

cylinder and

are

also

made

of

inserted pieces in

the

casting.

The crankcase

is

separable

at

the driving

shaft

side and this separable piece constitutes

the

main bearing cover.

4-2

MAIN BEARING COVER

As

the aluminium die-cast main bearing cover

is

built onto the crankcase on the driving shaft

side, the engine 'inside

are

reached

for inspection, easily by simply removing it. It

is

also

provided with

a

flange and

boss

for directly mounting operating machines such

as

generators

and pumps.

There

are

two

oil filters serving also

as

oil gauges provided

at

two locations.

(However, in

EY18-3

or

EY23

engine,

at

one location in

the

carburetor

side.)

4-3

CRANKSHAFT

The crankshaft is machined from

a

carbon

steel

forging with

an

induction hardened crank pin.

On

the

fan side,

the

breaker

cam is provided and on

the

driving side,

the

crankshaft

gear

is

force-fit.

44

CONNECTING ROD

and

PISTON

The connecting rod

is

machined from an aluminium alloy forging in which the

forged

alloy itself

serves

as

the

bearing metal

at

both

ends. On

the

large end, an oil scraper

for

splashing

the

lubricating

oil

is

provided.

The piston is machined from an aluminium alloy casting and

is

provided with two grooves

for

compression rings and one groove

for

the

oil ring.

4-5

CAMSHAFT

The camshaft is machined from

a

carbon

steel

forging with integral intake and exhaust cams

and

is

provided with a force-fit cam gear.

In

the

model B engine,

the

camshaft

serves

also

as

the

driving shaft, being driven

at

half

the

crankshaft speed.

In

the

EY14D, EY23D, EY25-2D

and

EY27-2D

engines,

the

camshaft is machined from a special alloy

cast

iron with an integral

camshaft

gear,

and is supported by aluminium bearing metals machined integral with

the

crankcase

at

both ends. (no

ball

bearing is used)

n

-4

-

4-6

VALVE ARRANGEMENT

The exhaust valve is positioned

in

the

upstream side of the cooling air with the result that the

exhaust valve

is

intensively cooled for engine life improvement.

-

4-7

CYLINDER

HEAD

A

Ricardo type combustion chamber

of

ample area is employed for good combustion efficiency.

The spark plug

is

mounted obliquely to facilitate fuel tank mounting.

4-8

GOVERNOR

The flyweight type governor effectively operates to maintain

the

selected speed at varying

load. The model

EY14, EY18-3

and

EY23

engine

is

equipped with a separate gearing for the governor

to

secure better performance.

4-9

COOLING

Cooling is accomplished

by

a

flow

of air circulated past the cylinder walls and head

fins

from a

combination fan-flywheel. The air

is

guided

by

a cylinder buffle

and

a head cover. The

EY14,

EY18-3,

EY23,

EY25-2

and

EY27-2

engines are equipped with curved vane fans made

in

two

modifications, each

for

direct drive and reduction drive engines.

4-10

LUBRICATION

Lubrication for rotating and sliding parts is accomplished

by

scooping and splashing the

oil

in

the crankcase

with

oil scraper attached to connecting rod.

4-11 IGNITION

The ignition system

is

of the flywheel magneto type

with

the ignition timing set

230

before T.D.C. The magneto comprises a flywheel, ignition coil and a breaker, of which the flywheel (serving also as a fan)

is

mounted on the crankshaft and the two other members are mounted

directly

in

the crankcase. (for details, refer

to

7.

MAGNETO

section)

The model

EY23

engine normally incorporates an electronic ignition system.

4-12 CARBURETOR

A

horizontal draft carburetor

is

employed. Its setting has been carefully determined after

through testing to achieve best starting, accelerating, fuel consumption, output and other

performances.

For

other details such as construction, refer to

9.

CARBURETOR

section.

4-13

AIR

CLEANER

The model

EY

14,

EY18-3

and

EY23

engines are equipped with an oval air cleaner incorporating

8

sponge element.

The cycl.one type air cleaner with a semi-wet double element is optional.

The

model

EY25-2,

EY27-2

engines are equipped

with

an

cyclone type semi-wet double element

air cleaner.

-5-

4-14

SECTIONAL

VIEW

of

ENGINE

4-14-1

MODEL

EY14

FI

Blower

ywheel

(Cooling

Housing

Starting

Pulley-

MODEL

EY14

ver

-6-

Fuel

Tank

MODEL

-7

EY14

-

4-14-2

MODEL

EY18-3

Cover

MODEL

EY18-3

-a-

/

/-

Tank

MODEL EY18-3

-9-

4-14-3

MODEL

EY23

Flywheel

Star

MODEL

EY23

7g

Cover

-

10

-

Con

/"

Tank

MODEL

-

EY23

11

Cam

Shaft

-

4-14-4

MODEL

EY25-2

and

EY27-2

MODEL

EY25-2

-

12

and

-

Cover

EY27-2

I

ti

I

\Cam

Shaft

MODEL

EY25-2

and

EY27-2

-

13

-

5.

INSTALLATION

The life, affected by contents must

5-1

When anchoring

ease

of

maintenance, frequency of

the

way

the

be

studied carefully.

INSTALLING

installing the engine,

or

supporting method must

check

and repair, and operating

engine is installed. When installing the engine, therefore, the following

its

position, coupling conditions with the operating machine and

be

carefully studied.

Especially, when deciding the installing position, consideration must routines such

maintenance of

5-2

VENTILATION

The

engine must

to

be

operated in a cover

re-circulation

the engine compartment

consumption, power reduction, seizure,

proper

below

5-3

Since gas

operation

50OC

EXHAUST GAS EVACUATION

the

must

influenced

as

filing and checking

air

cleaner and oil draining.

be

supplied with fresh air

or

in a small room, a proper means must

or

ducts and baffle plates

is

allowed

is

harmed. The temperature

of

gasoline

for

to

rise, vapor lock, oil deterioration, increase of

loss

and

oil,

checking of spark plug and breaker,

cooling and fuel combustion. When

guiding a cooling

of

engine life

of

the engine compartment must

air,

or

other troubles

even in summer with necessary ventilation arrangement.

exhaust

be

by

gas

from

evacuated

the

length

the

engine is toxic, when

to

outside. Since the output power

of

the

exhaust duct, its diameter must

the

engine

is

be

length.

cost

are

greatly

be

given

be

provided for cooling

to

facilitate

the

its

engine

air

because if the temperature in

oil

are

caused, and

be

maintained

operated indoors,

of

an engine

increased in proportion

the

exhaust

is

considerably

to

its

n

is

F-,

5-4

FUEL SYSTEM

When bottom surface lies within

When

the

When connecting

the

standard fuel tank is installed separate from

the

fuel tank is installed too low, fuel is not fed properly and if it is positioned

carburetor overflow

the

fuel pipe,

the

is

caused.

height

to

the

of

5

CL

50

cm from

the

eliminate air lock and vapor

engine, it must

fuel joint of the carburetor.

carefully examined for heat conductivity, diameter, bending, and standard I.D. of the fuel pipe is

5-5

5-5-1

Take

o

V-belts

o

The

o

The

POWER

BELT

the

driving shaft

driving pulley of

TRANSMISSION

DRIVE

following notes into condition:-

are preferred to

of

the

4

‘L

5

to

DRIVEN

flat

belts.

engine and

mm.

MACHINES

the

driven

the

shaft

of

the

driven pulley of

driven machine must

the

correctly.

o

The driving pulley must

o

As

far

as

possible,

o

When starting

the

engine,

the

be

mounted

belt

is spanned horizontally.

the

load must

as

near

be

the

engine

as

possible.

disconnected from

be

so

lock,

leakage

located

the

piping must

through fittings. The

be

that

too

high,

parallel.

its

be

driven machine must be aligned

the

engine.

o

If a clutch is

not

available, a tension pulley

or

-

other

14

-

means must

be

employed.

5-5-2

FLEXIBLE COUPLING

When

a

flexible coupling

is

engine driving shaft must

The

tolerances on

5-6

WIRING

5-6-1

The

dotted

1)

START

wiring

line

Point system

MODEL

is

are

EY14

the

runout and mis-alignment

by

RECOIL

indicated in

not wired in

Spark Plug

used,

be

STARTER,

the

runout and mis-alignment between

made

as

small

or

by ROPE

as

possible.

are

specified by

wiring diagram given below. Normally,

the

engine

at

the

\

'Ignition Coil

Lighting

factory.

~

Lighting

Coil

(Optional Equipment, available

Stoo Button

Switch

each

Lamp

the

driven

shaft

coupling maker.

the

portions indicated by

(6V-8V

',15W)

if

required)

and

the

MODEL

MODEL EY25-2, EY27-2

EY18-3

Contact Breaker

'

Lighting

,Condenser

la"

"-7

Coil

(Optional Equipment, available if

required)

ir

.ed

)

Fig.

-

5-6-

7

15

-

2)

Electronic ignition system

MODEL

Optional

Lamp

EY14:

Coil

CDI (Capacitor Discharge Ignition)

Stop

Button

Pulser

Coil

""".J

Fig.

58-2

system

BlackMlhite

MODEL

EY23

m7

STD:

"

L

TIC

Spark

(Transistor Ignition Circuit) system

Ignition Coil Connector

Plug

Fig.

i

5-6-3

Stop

Button

-

16

-

MODEL

EY23:

TIC

with

Lamp

Spark Plug

Lamp

Coil

System

/

Ignition Coil

Flywheel

Fig.

5-64

Stop Button

77!7

MODEL EY25-2, EY27-2:

Optional

Lamp

Coil

PIT

(Pulser

Ignition Pulser

etc.

\

Flywheel

Ignition Transistor)

Coil

Fig.

Spark Plug

I

5-6-5

system

1

Stop

Button

-

17

-

5-6-2

The wiring is

lines

CELL

is

normally not prepared

.

START

as

shown in the figure below. The section, in the figure, described with dotted

in

the

engine side.

,~

MODEL

EY18-3,

Plug

Spark

EY25-2, EY27-2:

Magneto Black

a

Point with

Starting Motor Magnetic Switch

Black

Cell

System

7777

EY18-3D,

-

8

BS

Wiring

JIS

CB Female

JIS

CA

JIS

LA106

Diagram

Terminal

Male Terminal

Board Terminal

-

18

-

MODEL

EY23,

EY25-2,

EY27-2:

PIT

with

Cell

System

Spark

plug

-

Flywheel

i

Magnetic

Switch

Starting

Motor

F&.

5-6-7

-19-

1)

Specifications

Parts

No.

Name

Manufacturer

Voltage

Output Weight

2147050110

(Model

EY18-3BS, 23BS,

2147050210

(Model

EY23DS, 25-2DS,

Starting

Motor

HITACHI

12v

0.6

kW

14

131.5

31.5

-

F&.

5-6-8

25-2BS, 27-2BS),

2

7-2DS)

2)

Operation

The battery

is

connected

to

the terminal

66

of

the magnetic switch.

The condition when

the

starting motor is

ON

is

as

shown in

the

figure below.

t

iM

“S

;.

Ijl

Starting

Motor

tM

Switch

4

Key

Switch

Fig.

5-6-9

This circuit consists

of

a

magnetic

switch

operating circuit and

a

starting motor operating

circuit.

When

the

key

switch

is

turned

ON,

the

-

circuit is closed, and electricity

flows

to

the

direction directed

by

an arrow,

thus the coil

of

the magnetic switch being excited

to

absorbe

the contact.

Then, power is supplied to

the

starting motor, and engine cranking

is

started.

so,

low

voltage

current

flows

in the

M

circuit, while

starter

current

for

a

large

current

flows

in

the

S

circuit.

M

*

Pinion

gear

engagement

When

the

starting motor

is

started,

the

wait assembled

with

the

helical

spline on

the

shaft

is

T-”.

moved

to

the

axial direction

by

centrifugal

force,

and push out the pinion gear

to

be

engaged in

the

ring gear.

-20

-

6.

DISASSEMBLY

and

REASSEMBLY

6-1

PREPARATION

and

SUGGESTIONS

0

1)

When

disassembling the engine, memorize the locations of individual parts

so

as to be able

to reassemble them correctly. Tag parts

if

there is a possibility

of

confusion.

'2)

Prepare several boxes

to

keep parts beginning to certain groups together.

3)

Group those parts related each other, tentatively assembling where they belong,

im-

mediately after removing,

in

order to prevent missing

and

misplacing.

4)

Handle the disassembled parts carefully and wash them

in

kerosene.

5)

Use

the correct

tools

in

the correct way.

6)

Standard tools required for disassembling and reassembling:

a)

Work

table

b)

Washing pan

c)

Disassembling tools

d)

Washing

oil

(kerosene

or

gasoline), Mobile oil

e)

Emery

paper, cloth

when the oil drain plug on the crankcase side wall

on

the carburetor side

is

unscrewed.

and flywheel to the specified

torque

values.

7)

Before starting

to

disassemble the engine, drain fuel and lubricant.

Oil

can be drained

8)

Tighten the screws

of

the cylinder head, main bearing cover, connecting rod, spark plug,

9)

Use new packings and gaskets

in

reassembly.

10)

Immedaitely before assembling parts, wash them

in

fresh gasoline

or

kerosene and blow

them dry.

0

11)

Apply Mobile oil

on

rotating and sliding parts.

12)

Take care not to contaminate the parts

by

dust during assembling.

13)

Tighten bolts, nuts and screws with proper torque according to the their sizes.

If

small

14)

After completely assembling the engine, turn it

by

hand and check

if

there

is

any

screws are tightened too tight, they may get broken.

abnormality

or

loose members.

6-2

SPECIAL

TOOLS

Flywheel Puller

Valve

Guide Puller

Valve

Seat Cutter

Spring Compressor

Fig.

6-2

-21

-

Description

Part

No.

QtY

Remarks

1

Flywheel Puller

Bolt

Spring

Compressor

I

Valve Guide Puller (Plate,

Shaft,

Nut)

Valve Seat Cutter

6-3

DISASSEMBLY

6-3-1 FUEL

1)

Disconnect fuel pipe between strainer and carburetor

2)

Remove fuel tank from

3)

Remove tank EY27-2: 10 mm flange nut, 4 pieces)

6-3-2 BLOWER HOUSING and HEAD COVER

1)

Remove blower housing from crankcase and head cover (cylinder baffle).

(EY14: 6 bolt, 6 pieces)

2)

Remove head cover (cylinder baffle) from cylinder head.

TANK

x

and

REASSEMBLY

and FUEL TANK BRACKET

bracket.

bracket

8

mm Flange bolt, 6 pieces/EY18-3,

from cylinder

209 95004 07

001

6608500

2079500307 Valve

I

205 95001 206 95001 07 EY 18-3, EY 23

207 95001 07 2079500207

07

PROCEDURES

(8

mm

nut,

head

1

3

1

I

1

I

1 1

1

4

pieces)

(EY14: 8 mm flange nut/EY18-3, EY23, EY25-2,

EY23,

EY14, EY18-3, EY23, EY25-2, EY27-2

I

EY

I

at

(EY14:

14

EY25-2, EY27-2 EY14, EY18-3, EY23, EY25-2, EY27-2

carburetor side.

3

pieces)

EY25-2, EY27-2: 6 x 12 mm Flange

I

-

6-3-3 AIR CLEANER

1)

Remove air cleaner cover and element.

2)

Loosen two bolts and remove air cleaner

2

pieces/EY18-3, EY23, EY25-2, EY27-2:

same

3)

Disconnect breather

4)

In

element thoroughly and apply mixture'of 4 excess oil before reinstalling it.

6-3-4 MUFFLER Remove muffler from cylinder part of crankcase. (EY14, EY18-3, EY23, EY25-2, EY27-2:

nut, 6-3-5 GOVERNOR LEVER and CARBURETOR

1)

Remove governor lever from governor

2)

Remove governor rod and

3) Remove carburetor from cylinder part

In

6-3-6 STARTING PULLEY and MAGNETO

1)

Remove starting pulley from flywheel.

bolt, 3 pieces)

time,

reassembly, wash element in kerosene shaking well until

2

pieces)

reassembly, refer

disconnect choke knob

pipe.

rod

spring from carburetor.

to

8.

GOVERNOR ADJUSTMENT section.

that

case

6

x

10 mm bolts,

is

connected

part

shaft.

of

(EY14:

(6

crankcase.

from carburetor. (EY14: 6 x 8 mm Flange bolt

'2

pieces) (EY25-2, EY27-2:

to

carburetor choke lever.)

dirt

is

sufficiently removed. Dry

kerosene and 1 part Mobile oil. Squeeze out

mm

bolt,

6 x 12

1

pieces)

(6mm

nut, 2 pieces)

mm bolt/EY25-2,

EY27-2:

8

x

at

8

12

the

mm

-

22

-

0

Remove flywheel

2)

a

Apply

socket wrench over the flywheel

nut and give the wrench

a

soft hammer. Remove nut and spring

washer. (EY14:

from

crankshaft.

a

sharp blow with

12

mm nut/EY18-3, EY23,

EY25-2, EY27-2: 14 mm nut)

to

Attached flywheel puller

flywheel

illustrated in Fig. 6-3-1, turn center clockwise until flywheel becomes enough

Remove spark plug cap from high tension

3)

cable

coil from crankcase.

and washer,

Take off the point cover and remove

4)

to

be

removed.

of ignition

2

pieces)

coil

and remove ignition

(6

x

25 mm screw

as

bolt

loose

I

Flywheel Puller Flywheel

Fig.

6-3-

7

contact breaker and condenser, from

crankcase (All models of the EY23 engine

are

electronicallv ignited.)

In reasseambling magneto, refer

5)

"

to

7-2 BREAKER POINT ADJUSTMENT, and 7-3 TIMING

ADJUSTMENT.

6-3-7 CYLINDER HEAD and SPARK PLUG

1)

Remove spark plug from cylinder head.

2)

Unscrew mounting nuts/bolts and remove cylinder head from crankcase. (EY14: 8 mm flange

10

bolt/EY18-3, EY23, EY25-2, EY27-2:

mm flange nut)

3) Remove cylinder head gasket and baffle (head cover) from crankcase.

4) In reassembly;

*

Clean carbon from combustion chamber and dirt from between the cooling fins

its

head. Check

*

Torque 8 mm flange bolt in EY14

3,

EY23 to 330 % 360 kg-cm (23.8% 25.9 ft-lb), and those in EY25-2, EY27-2

mounting face for distortion. Use new head gasket.

to

190 2.20 kg-cm (13.7.> 16.6 ft-lb),

10

rnm

of

nuts in EY18-

to

340 % 370 kg-

cm (24.6 -26.8 ft-lb).

*

Leave spark plug out temporarily, for

and

for

timing adjustments. When mounting spark plug, tighten

ease

in turning engine over for remainder

it

to

230

of

assembly

Q,

270 kg-cm

(16.6 %19.5 ft-lb) torque in models EY14, EY18-3, EY23, EY25-2 and EY27-2.

cylinder

6-3-8 INTAKE and EXHAUST VALVES

1)

Remove tappet cover and breather plate from crankcase.

2) Lift valve spring

by

means tool (valve spring compressor) and remove retainer locks and valves. same way both haust valve.

(See

for

intake valve and ex-

Fig.

6-3-2)

Then, remove valve springs and spring

retainers.

CAUTION:

DO

SURFACE THE COMPRESSOR

3)

In

reassembly;

*

Clean carbon and gum deposits from the

NOT DAMAGE GASKET

OF

TAPPET CHAMBER WITH

TOOL.

of

compressor

Proceed

in

the

I

Fig.

6-3-2

-

23

-

Replace valves if

or

warped.

Correct

cutter

the

tool

as

The finished

the

valve

seat

by

using

illustrated in Fig.

seat

width should

face

be

is

pitted

4S0

6-3-3.

1.2

seat

~1.5

mrn. Valve guides should

be

replaced when

valve stem clearance becomes excessive.

(See

Fig.

6-34)

Draw valve guides out using -valve guide

puller

tool

as

shown

in

Fig.

6-3-4

and

press new guides in, using the same puller

tool.

Assemble valve springs and spring tainers

after

adjusting tappet

t3"

1

clearance.

re-

Valve Seat Cutter

Fig.

6-3-3

A

-

VALVE FACE ANGLE

B

-

SEAT ANGLE

/

C

-

GUIDE INSIDE DIA.

D

-

VALVE

MAXIMUM ALLOWABLE CLEARANCE BETWEEN Cand

STEM

DIA.

(

D

):

EY14

INTAKE

EXHAUST

i

INTAKE

I

EXHAUST

VALVE

Guide

EY14 EY18-3, E23, EY25-2, EY27-2

45O 45"

+0.015

6

dia.

0

-0.025

6

dia.

-0.040

-0.075

6

dia.

-0.095

i

0.025L-

0.075L-

and

VALVE GUIDE CLEARANCE

Fig.

6-3-5

0.055L

0.1

1OL

I I

Fig.

6-3-4

7

.7

0.056L- 0.098L

4

45O

dia.

5O

N.036

N.016

-0.040

-0.062

L:

Loose

-

24

-

4)

Tappet Adjustment (See Fig.

6-3-6)

With tappet

in

its lowest position, hole

valve down and insert feeler gauge

between valve and tappet stem. The clearance

for

both intake and exhaust,

with engine cold, must be and

0.16

%

0.20

mm

for

EY14,

EY18-3,

EY23, EY25-2

and

EY27-2.

If

the clearance is less than it

should be, grind the end

of

valve stem a

very little at a time and remeasure.

If

the clearance

is

too large, sink valve

seat with seat cutter tool. After obtaining correct clearance, assemble valve springs and spring retainers,

and

secure them

in

place with the re-

tainer

locks.

Check

operation

of

valves

by

turning crankshaft over

by

hand and

remeasure tappet clearance.

6-3-9

MAIN BEARING COVER

Fig.

6-3-6

Remove mounting screws.

(EY14:

6

mm

bolt and washer

7

pieces/EY18-3,

EY23, EY25-2,

EY27-2:

8

mm

bolt 8 pieces)

Tap around outer surface

of

main bearing cover with a soft hammer to break it loose and

carefully remove it,

so

as not to damage oil seal.

In

reassembling

EY14,

EY18-3

and

EY23

main bearing cover, install governor gear and governor

sleeve inside it

first,

and make sure that governor shaft is already installed in crankcase.

In

this case,

in

order to prevent damage

of

governor gear (made

of

plastics) which has been installed inside main bearing cover, reassemble main bearing cover to crankcase, making sure that governor gear mesh

with

cam gear.

In

reassembling

EY25-2,

EY27-2

main bearing cover, mount governor yoke inside main bearing

cover before remounting it. (See Fig.

6-3-7)

If

oil seal must

be

replaced, force fit

a

new

oil seal

in

main bearing cover before mounting it.

In

reassembling main bearing cover, apply oil to bearing surfaces, gear train, tappets and oil

seal lips and form a light film

of

oil

on

main bearing cover face to hold gasket in place. Mount

an

oil

seal guide

on

to the crankshaft to prevent damage to the oil.seal lips. (Fig.

6-3-8)

Confirm that crankshaft end play is

0

~0.2

mm.

If

necessary, adjust it with adjusting collar.

(See

Fig.

6-3-9)

Fig.

6-3-7A

(EY14, EY18-3, EY231

(Model

Bl

Fig.

6-3-

7B

(E

Y25-2, E Y27-21

(Model

D)

-

25

-

Fig.

6-3-8

*

Correct fastening torque

Adjusting

Collar

for

main bearing cover mounting screws is: EY 14 80 %lo0 kg-cm (5.7% 7.2 EY18-3, EY23, EY25-2 and EY27-2

170 ~190

kg-cm

(12.2 Q 13.7

Fig.

ft-lb)

6-3-9

ft-lb)

CAUTION: Fig. 6-3-9 SHOWS ONE METHOD

PLAY.

THE DISTANCE BETWEEN THE MACHINED SURFACE

ADJUSTING COLLAR IS MEASURE’D. THE COMPRESSED THICKNESS

COVER

PACKING IS 0.25

mm

(EY14, EY18-3 and EY23) and 0.15

OF

MEASURING THE CRANKSHAFT END

OF

CRANKCASE AND

mm

(EY25-2, EY27-2)

OF

TAKE THIS THICKNESS INTO CALCULATION WHEN DETERMINING THE END PLAY.

6-3-10 CAMSHAFT and TAPPETS

1)

Remove In

this

on its side

2)

Withdraw tappets and

camshaft from crankcase.

ease,

as

to

prevent tappets from falling out and becoming damaged, turn crankcase over

shown in Fig. 6-3-10.

mark

them

for

identification with the hole

from

which they were

removed.

3)

In reassembly; *put tappets Do not forget

*

Timing If valve timing 6-3-1

1)

to

marks

mount thrust sleeve on camshaft. on camshaft gear and crankshaft gear must

is

off,

back

engine

in their corresponding

will

not function properly

hole

first and then mount

be

matched

or

may not

up.

run

at

all.

BEARING

camshaft.

(See

Fig.

-,

F3.

6-3-

70

I

Fig.

6-3-

1

-

26

-

6-3-11

1)

2)

3)

CONNECTING

Straighten Take off

oil

Scrape off

ROD

out

the

bent

scraper, rod

all

carbon deposits

and

tabs

lock

PISTON

of

rod lock washer and remove

washer and connecting

that

might interfere with removal

cylinder.

4)

Turn crankshaft until piston is

and

out

through top

5)

Remove piston from connecting rod by taking out

of

cylinder.

at

top, then

pin.

6)

Remove piston rings from piston by widening In

7)

reassembly;

push

connecting

the

open ends.

bolts

rod

cap..

two

clips and then removing

from connecting rod.

of

piston from upper end of

rod

and piston assembly

the

upward

piston

PISTON RINGS (See Fig.

a)

If an expander

tool

is not available, install rings by placing the open ends on first land far enough

to

of

piston, spread ring only

slip

over piston and carry it

6-3-12)

of

into correct groove. Be extremely careful not brake ring. Assemble rings in

oil

ring, second ring and top ring. (See

Fig.

6-3-13)

PISTON and CONNECTING

b)

to

distort and

the

ROD

order

Assemble piston and connecting rod inserting piston pin. Be sure

at

clips

both ends of piston pin.

to

When installing connecting rod, use piston ring compressor

Fig.

rod

6-3-14

so

that

and position

the

as

mark

illustrated in

the

connecting

on

it

faces

flywheel side. Prior

to

installing

the

connecting rod, oil the piston rings, large end bearing and cylinder wall amply. Stagger the piston ring gaps around To

the

piston.

.determine

the

clearance between

900

piston and cylinder, measure the diameter

of

the piston in the center

at

faces

Turn crankshaft

the bottom

to

of

the piston skirt.

bottom of stroke and

of

the

tap piston down until rod contacts crank pin.

Mount connecting rod cap matching marks on connecting rod.

*

Install

tabs

*

Check

a

new rod

positively.

for

free

lock

washer

movement

and

bend the

of

connecting

rod after assembling.

the

insert

apart

thrust

ring

of

by

a

the

/I

Fa.

6-3-

F

is.

6-3-

F

is.

6-3-

12

...

.......

!"&

.......

I

13

Second

Oil

Ring

Piston

Ring

Guide

Fig.

6-3-

14

-

27

-

The

correct

torque values

EY

14

EY18-3

EY

23

EY25-2

EY

27-2

90

%

170 % 200 200 % 25Okg-m (14.4 % 18.0 ft-lb)

connecting

are

as

115

kg-cm

rod

follows:

(6.5

cap fastening

%

kg-cm (12.3 % 14.4 ft-lb)

8.3

ft-lb)

Refer

to

chart

Fig.

6-3-15

for

clearance

between piston, cylinder and connecting

I

D

(crankshaft pin Dial

I I

W

(crankshaft

I

~~&~N$~>!~~~~R

I

PISTON RING GAP

PISTON RING SiDE CLEARANCE IN

GROOVES

CONNECTING

TO

CRANK PIN

CONNECTING PISTON PIN TO PISTON 10.009T-0.01 L )0.009T-O.01 L 10.009T-0.01 L 10.004T-0.015L L:

LOOSE,

ROD

T: TIGHT

Width)

TO

AT

PISToN

TOP RING

RING

OIL

SIDE

PISTON PIN

EY14

23.4

kO.1

10.037L-0.075L

1

0.20L-0.40L

0.05L-0.095L

0.04L-0.085L SECOND RING

0.01

L-0.055L

0.05L-0.076L

0.01 L-0.029L

rod.

EY

18-3 EY 23 EY25-2 EY27-2

25

+0.1

1

0.03L-0.069L I 0.03L-0.069L

1

o.o~L-o.~~L

0.04L-0.085L.

0.1L-0.3L 0.2L-0.7L

0.01L-0.029L

1

25

2.'

1

o.o~L-o.~~L

0.04L-0.085L

0.037L-0.063L 0.037L-0.063L

If

JWL

I

27

2.'

1

0.06L-0.99L ~0.072L-O.111L

I

o.o~L-o.~~L

0.04L-0.085L

0.1

L-0.3L 0.1 L-0.3L

0.021 L-0.04OL 0.01 L-O.C29L

1

27

2.'

1

o.o~L-o,~~L

0.05L-0.095L 0.05L-0.095L 0.05L-O.OQ5L 0.05L-0.095L

0.04L-0.085L

0.01 L-0.055L 0.01 L-0.055L 0.01 L-0.065L 0.01 L-O.055L

0.04L-0.066L 0.04L-0.066L

0.1

L-0.3L

0.021 L-0.040L

I

0.004T-0.015L

I

6-3-12

1)

2)

3)

*

CRANKSHAFT

Remove woodruff key Remove crankshaft from crankcase

tapping lightly

damage In

reassembly; Attach

of

the

crankshaft and mount crankshaft in

crankcase

If

an

oil

seal

crankshaft damage lips of

at

its end. Take

oil

seal.

as

shown in Fig.

guide

with

extreme

oil

seal.

is

(for

magneto).

care

oil

seal

guide on end

6-3-16.

not available,

care

so

as

Fig.

by

not

to

mount

not

to

-

6-3-

75

I

28

-

Crankshaft

Fig.

6-3-

16

7.

MAGNETO

7-1

MAGNETO

The spark for ignition

is

furnished by a magneto in models EY14,

EY18-3,

EY23, EY25-2 and

EY27-2. In these models, magnetos manufactured

by

KOKUSAN DENKI K.K.

are

used.

(The

model

EY23

is

based on noncontact ignition system.)

The

magneto consists

of

a

flywheel, ignition coil, and breaker assembly (including condenser),

of

which flywheel

is

mounted on crankshaft and ignition

coil

and

breaker

assembly

are

mounted in

crankcase directly.

7-2

BREAKER POINT ADJUSTMENT

The

breaker points, which

are

mounted in

the

crankcase inside the flywheel should

be

checked twice

a

season

or

whenever the

ignition

spark

becomes weak. If

there

is

evidence

of

pitting

or

pyramidding,

the

breaker points must

be

corrected, and then

it

becomes necessary

to

readjust

the

gap

to

its

proper clearance. (0.35 mm, 0.014 inch)

The

normal

breaker

point opening

is

0.35

mm

at

full

separation. Since

the

spark timing

of

23O

is

regulated by

the

point opening, use

a

timing

light

to

obtain an accurate

spark

advance.

To

adjust

breaker

point opening, remove

starting pulley, blower housing and flywheel from

the

engine and proceed

as

follows.

(See

Fig.

7-2)

1)

Remove

breaker

cover

from

contact

breaker.

2)

Turn crankshaft over until

breaker

arm

comes in contact with

the

high

point

of

the

breaker cam. (maximum point opening

of

0.35

mm)

3)

Loosen contact support plate

lock

screw,

just enough

so

that

bracket

can

be

moved.

4) Insert

a

0.35

mm feeler gauge between

the

points.

CAUTION: ADJUST BREAKER POINT GAP

WITHOUT OPENING

IT

MORE THAN

2

mm,

OTHERWISE RATED

HEEL-

PRESSING FORCE

MAY

NOT OBTAINED

DUE TO

THE

BENDING OF CONTACT

BREAKER ARM.

5) Insert

a

0.35

mm feeler gauge between

the points.

I

Fig.

7-2-A

(EY74, EY

18-31

Fig.

7-2-6

(E

Y25-2, E y27-21

6)

Apply a screw driver

to

adjusting

tab

and move

the

contact support plate just enough

so

that

7)

Tighten

lock

screw and

recheck

breaker

point

gap.

8)

Pull a strip

of

8

%lo

rnm wide white paper through

the

closed

points

to

remove oil and dust.

CAUTION: IN THIS CASE NEVER OPEN THE BREAKER POINT

GAP

MORE

THAN 2

mm.

9)

Mount flywheel, blower housing and starting pulley on engine after adjustment.

a

slight

drag

is

felt while sliding

the

feeler gauge

from

between

the

points.

-

29

-

7-3

TIMING

With

the

before

the

controlled by opening

However,

using a timing

For

timing adjustment, the following alignment

EY

14:

EY25-2 EY25-2 EY18-3:

ADJUSTMENT

Model

EY14, EY18-3, EY25-2

piston reaches TDC on

the

breaker point opening and

is

adjusted according

the

advance timing

light

as

shown

D

&

B

&

EY27-2

EY27-2 B

D

type: D mark

type: 3 mark

the

to

the

BREAKER

is

more accurately adjusted through

in

Fig.

7-3-1.

Projection

M

mark and

at

M

mark and

at

M

mark and

M

mark and relief line

M

mark and

and

compression

at

lower left crankcase

upper

slit

EY27-2

this

POINT

marks

upper left

slit

on flywheel circumference

engines,

stroke.

advance

are

is

ADJUSTMENT

provided.

crankcase

the

This spark advance

obtained when

(see

slit

on flywheel circumference

left

crankcase

slit

on flywheel circumference.

at

upper left crankcase

on flywheel circumference

spark

Fig.

is

timed

to

0.35

the

following procedures,

7-3-2)

the

mm

to

breaker

(0.014

occur

of

23O

point

inch).

23O

is

n

Flywheel

Fig.

7-3-1

For

timing adjustment, the following procedures using a timing light:

the

Disconnect

stop button

Remove blower housing

of

the

Connect one crankcase. (See Fig.

While

the

points

timing

7-3-1)

are

open, the

W

lead

from

engine.

light

wires and

leads

the

coil primary wire.

to

the coil primary wire and ground

remains on and when

the

extinguished.

(D

Turn flywheel slowly counter-clockwise

the

light extinguishes.

Then, turn flywheel very slowly clockwise

the

mark

moment

on

engines) and stop immediately flywheel

the

If

the

procedures

After

primary

is

in

the line with

timing

is

cowect.

timing mark lines are not in alignment, then re-adjust the point opening according

BREAKER

completing

lead

POINT

3)

through

to

the

ADJUSTMENT,

5).

the

timing adjustment, re-mount

stop button.

the

type engines)

(D

type engines)

the

light lights

the

crankcase. When the mark line is

by

removing

the

or

the

flywheel and repeat

blower housing and connect

Fig.

7-3-2

points are

clockwise

or

up.

!I3

counter+lockwise

Check if tine

the

other

closed,

the

lead

light

to

is

type engines) until

(B

type

slit

on

the

in

alignment,

to

the

checking

the

coil

/1

-30

-

7-4

MAGNETO TROUBLE SHOOTING

When the engine does

following

1)

Check ignition cable for possible corrosion, broken, worn insulator

2)

Check the sparking

3)

Check if the breaker points require cleaning,

tests wiU clarify if they are caused

corroded or pitted. (Condenser may have Refer to

4)

If

no

*

SPARK

Remove spark

"BREAKER POINT ADJUSTMENT".

spark takes place, replace ignition coil.

TESTING

plug

not

as

from

start

described later

or

starts

with

in

this

difficulty,

by

a defect

section.

or

to

be replaced.)

cylinder head and place it

or

in

the magneto.

adjusting

on

blower housing, with the ignition cable

connected to it.

Crank the engine several times

spark plug.

If

the

spark

is

by

starting pulley and observe the spark

strong, the ignition system can be eliminated as the source

trouble.

If

the spark is weak or there is

through

3)

above.

The

correct electrode gap

no

spark at

all,

repeat the checks according to the procedures

is

0.6

Q

0.7

mm

(0.024

when

or

its

operation is unstable, the

or

loose connection.

not.

%

If the points are badly

in

the spark gap

0.028

inch).

of

1)

-31

-

8.

GOVERNOR

ADJUSTMENT

In

the model

EY

14,

EY 18-3, EY23, EY25-2

and

EY27-2

engines, a centrifugal flyweight type

1’1

governor

is

used. The flyweight assembly is mounted

on

a

separate governor gear

in

EY14,

EY18-3

and

EY23

and on the camshaft gear

in

EY25-2

and

EY27-2,

and automatically regulate

the throttle valve

of

the carburetor

in

such a way that the engine speed is maintained constant

under varying loads.

1)

Connect carburetor throttle lever and governor lever with governor

rod

and mount governor

2)

Connect the governor lever and the rotation adjusting lever with a governor

spring,

and set

the rotation adjusting lever to the crankcase.

3)

Turn

control lever clockwise

(EY14,

EY18-3, EY23)

or counterclockwise

(EY25-2,.

EY

27-2)

until throttle valve

in

carburetor is opened

fully.

Lock

control lever in this

position.

4)

With a screw driver inserted

in

the groove of govenor shaft, turn it clockwise

(EY14,

EY18-

3,

EY23)

or

counter-clockwise

(EY25-2,

EY27-2)

fully

(until it will not turn any more) and

then lock governor lever to governor shaft by tightening clamp bolt.

lever

on

governor shaft.

Governor

Rod

\

Governor Spring

Fig.

8-1

-

32

-

9.

CARBURETOR

9-1

OPERATION

and

CONSTRUCTION

(See

Figs.

9-1-1

and

9-1-2)

9-1-1

FLOAT

SYSTEM

The float chamber located directly beneath the main carburetor structure serves to maintain

at

a

the fuel level incorporated in

it.

constant height by a joint action

Fuel from the fuel tank enters

while

cousing

the

fuel level

the

Throttle

Pilot

is

low

float to move up.

Valve

Outlet

but is

the

float chamber through the needle valve, which

closed

when

the

fuel

of

level

the

reaches

float

and the needle valve

is

kept open

a

predetermined level

I

F

is.

-33

9-

7

-2

-

9-1-2

The

through

jet

outlet

PILOT

SYSTEM

pilot system supplies fuel

the

main

jet

and

is

then regulated by

and

by-pass.

is

measured by

the

to

the

engine during idle and low

the

pilot screw

pilot jet

before

to

mix with

the

being supplied

speed

air

to

operation.

The

fuel taken

measured by the pilot air

the

engine through

the

,-

pilot

During

9-1-3

idle

operation, the engine

MAIN

SYSTEM

is

supplied with fuel mainly through the pilot outlet.

During medium and high-speed operation, fuel supply

system, in which fuel flow supplied through the main

where main nozzle the mixture

with intake

9-1-4

The

the

is

CHOKE

choke

fuel

is

mixed with air, the flow

metered

then discharged through the top of the main nozzle

air

to

become

SYSTEM

system aides starting in

engine is cranked with

so

that

more fuel

9-2

DISASSEMBLY

is

introduced into

and

Besides mechanical failures, most troubles most common

causes

of passages, and variations in carburetor,

without restriction.

the

air cleaner and carburetor must

(See

rate

is

controlled by the main

jet

where

the

flow

rate

air

is

admitted through the bleed holes

the

optimum air-fuel mixture

the

cold

season by enriching

the

choke

REASSEMBLY

closed,

the

vacuum applied

air flow

are

incorrect fuel-air mixtures

the

fuel level.

Fig.

9-2-A,

9-2-B

or

9-2-C.)

rate

of

to

In

to

the engine

jet.

is

controlled, and through the main nozzle,

which is controlled

as

to

be

supplied

the

to

the

is

controlled in the main

In

the main system, fuel

by

the main

to

mix with the fuel. The

air

atomized fuel where it mixes

to

the

engine.

air-fuel mixture. When

main nozzle is made higher

make a starting easy.

attributed

are

order to obtain

be

maintained clean

to

an incorrect mixing ratio.

clogged

jets,

the

restricted

full

performance

so

that

air

air and fuel

jet.

and fuel

In

of

is

the

The

the

flow

n\

9-2-1

1)

2)

9-2-2

1)

2)

9-2-3

1)

2)

3)

THROTTLE

Unscrew Philips Take

care

not

SYSTEM

head

screw

to

damage ends

(16)

and remove

of

throttle valve.

throttle

Remove throttle stop screw (20) to remove spring

CHOKE

Unscrew Philips screw

model

Remove them beforehand When assembling

PILOT

Remove pilot jet Unscrew pilot screw

SYSTEM

EY25-2,

SYSTEM

(lo),

remove

EY27-2 engines have

to

prevent them from being

choke

(23).

shaft,

Use

(22)

the

flat on

correct

and

remove spring

tool to prevent damage.

choke

valve

ball

(21).

Reassembly

a.

Tighten

b.

Replace pilot screw

pilot

jet firmly

if

to

prevent

fuel

leakage

tapered end is diformed.

valve

(19).

(11)

and

(24)

and

choke

lost.

valve must

and

a

possible

Do

not overtighten.

(17)

and throttle shaft

take

out

choke

be

toward

spring

(25)

the

poor

engine performance.

shaft

in

the

main

(18).

(12).

carburetor.

air

jet

side-

The

-

34

-

9-2-4

MAIN

SYSTEM

1)

Remove main jet holder

(9)

and dismount

2)

Remove main

jet

(8)

from main jet holder

'3)

Remove main nozzle

(2)

from carburetor

4)

Reassembly

float chamber-bowl

(6).

(9).

body.

a.

Tighten main jet securely to main jet holder.

If

not tightened securely an engine disorder may result through a too rich

fuel

mixture.

b.

Tighten main jet holder to

90

kg-cm

(6.5

ft.

lbs)

torque.

9-2-5

FLOAT SYSTEM

1)

Extract float

(5)

and remove float

(4)

2)

Reassembly

and needle valve

(14).

Whenever needle valve

is

replaced, re-

place valve seat as well, installing a

matching needle valve and seat assembly.

CAUTION: NEVER USE A DRILL OR A

METAL WIRE

TO

CLEAN JETS. THEY

ARE LIABLE

TO

DAMAGE

THE ORIFICE AND CAUSE AN ENGINE MALFUNCTION. BLOW AIR

TO

CLEAN THEM.

23

17

rn

18

12

11

7

10

13

Fig.

9-2-A

(EY74, EY18-31

7

8

9

Fig.

9-2-C

(E Y25-2,

EY27-21

Fig.

9-2-6

(E

Y23/

-35

-

9-3

ADJUSTMENTS

1)

Pilot screw is adjusted by'back screwing (counter-clockwise)

after

closing

it

fully once.

EY14

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

1

turn

EY 18-3

BV18 2

turn

BV21

...........

1

turn

EY23 BV21

...........

1-3/8

turn

EY25-2 BV24

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

1-5/8

turn

EY27-2 BV24

...........

1-1/2

turn

...........

CAUTION:

DO

NOT OVERTIGHTEN PILOT SCREW WHEN CLOSING IT FULLY.

2)

Turn

throttle

stop screw clockwise until

the

specified idling speed

of

1200

+loo

rpm

is

THE NEEDLE POINT MIGHT BE DAMAGED BY OVERTIGHTENING.

obtained. When

the

idling speed

is

higher

than

1200

+io'

rpm turn

it

counter-clockwise.

and engine

at

8

normal operating temperature.

3)

,

Make

final adjustments to

the

pilot

screw

and

throttle

stop

screw

with air cleaner mounted

-36

-

10.

RUN-IN OPERATION

of

REASSEMBLED

ENGINE

An overhauled engine must be carefully run-in

to

get

proper surface condition on newly

installed parts. Especially when

cylinder,

piston, piston rings

or

valves

are

replaced, a thorough run-in operation

is

indispensable.

The recommended run-in schedule is

as

follows:

r

I

1

LOAD

EY14 EY27-2 EY25-2

EY 23

EY18-3

SPEED

TIME

NO

LOAD

10

minutes

NO

LOAD

3,000

rpm

10

minutes 2,500 rpm

I

NO

LOAD

I

3,600

rpm

I

10

minutes

I

1.25 HP 60 minutes

3,600 rpm

5.5

HP

5

HP

4.5

PS

3.5

HP

2.5

HP

30

minutes 3,600 rpm 2.75 HP

2.5 HP

2.25

PS

1.75

HP

-

37

-

11.

TROUBLE

SHOOTING

For

a

satisfactory

starting

and running conditions of

a

gasoling

engine, the following three

requirements must be met:

1.

The cylinder filled with a proper fuel-air mixture.

2.

An appropriate compression

3.

Good

If

are

back

troubles

11-1

11-1-1

1)

'No

2)

Carburetor insufficiently choked, especially when engine is cold.

3)

Water, dirt

4)

Inferior

5)

Needle valve in carburetor held open by

continuous fuel drip

all

spark

three

also

at

correct time

requirements

other

factors

pressure, which contribute

are

given below.

STARTING

FUEL

DIFFICULTIES

SYSTEM

gasoline in fuel tank,

or

gum in gasoline hindering flow

or

poor

grade

from

gasoline not vaporizing satisfactorily

Sometimes, this trouble is remedied by lightly tapping handle

6)

Due to carburetor flooding, making When

pulley

or

the like.

the

mixture

this

happens, remove spark plug and turn

to

evacuate over-rich mixture through the plug

too

in

the cylinder.

to

ignite the mixture.

are

not met simultaneously, an engine can not be started.

such

as

or

heavy load

fuel

cock

to

at

starting and too long exhaust pipe causing

hard starting.

closed.

of

dirt

the carburetor during idling.

too

much fuel introduced in

rich

to

be

ignited.

The

most common

fuel

to

carburetor.

to

produce

or

gum.

This

condition

the

float chamber with

the

engine over several times with starting

hole.

Keep carburetor choke open

during this operation. Dry spark plug thoroughly and reinstall, and try

There

high

causes

correct

is

cylinder through cranking,

to

start

of engine

fuel mixture.

ascertained by

a

screw

driver

again.

c\

n

11-1-2

When the fuel system and the ignition system are eliminated and

1)

2)

3)

COMPRESSION

loss

of

power, the following

SYSTEM

are

to be checked

for

Cylinder dry after long interruption of operation. Loose

escaping mixture gas in compression

Damaged

or

broken spark plug. In

head

gasket

or

slack

this

case,

stroke.

cylinder

a

hissing noise is audible, during cranking, made by

head

tightening. A similar hissing noise

as

possible

lack

during compression stroke.

4)

Tappet clearance incorrect. (See

If

the

compression

dismantled and

1)

Valve

2)

Piston rings stuck

stuck

from engine and clean,

is

the

foliowing

open

not recovered after correcting the above faults,

due

to

carbon

in

piston

correct

must

due

"6-3-8,

be

checked.

or

gum

to

carbon accumulation. Remove pistor! and connecting

or

replace parts.

4)

Tappet Adjustment'!)

OR

valve stem.

-38

-

the

cause of starting difficulties

of compression.

is

produced

the

engine must

be

partly

rod

n

11-1-3

ELECTRIC

SYSTEM

When there is no spark, the following must be checked.

1)

Disconnected cable leading to ignition coil, spark plug or contact breaker.

2)

Broken ignition coil winding, causing short circuit.

3)

Wet

or

oil soaked spark. plug cable.

4)

Dirty

or

wet

spark plug.

5)

Incorrect spark plug electrode gap.

6)

Short connection

of

spark plug.electrodes.

7)

.Pitted

or

fused

breaker points.

8)

Sticking breaker

arm.

9)

Leaking

or

grounded condenser.

10)

Incorrect ignition timing.

11-2

ENGINE

MISSES

1)

Incorrect spark plug electrode gap.

2)

Worn and leaking ignition cable.

3)

Weak spark.

4)

Loose connections

in

ignition wire.

5)

Pitted

or

worn breaker points.

6)

Gasoline containing water.

7)

Poor compression.

11-3

ENGINE

STOPS

1)

Fuel tank empty. Gasoline contaminated

with

water, dirt

or

gum.

2)

Gasoline vaporized

in

fuel lines due to excessive heating around engine. (Vapor lock)

.3)

Vapor lock in

fuel

lines or carburetor due to the use of too volatile winter

gas

in the hot

4)

Air vent hole in fuel tank cap plugged.

5)

Seizure in rotating

or

sliding pairs

in

engine due to lack

of

oil.

6)

Ignition troubles.

season.

114

ENGINE OVERHEATS

1)

Crankcase oil supply

low.

Replenish immediately.

2)

Incorrect spark timing

3)

Low

grade gasoline

is

used.

Engine overloaded.

4)

Restricked cooling air circulation.

5)

Cooling air partly misdirected causing loss to cooling efficiency.

6)

Cylinder head cooling fins blocked with dirt.

-39

-

7)

Engine operated

in

closed space without fresh

supply

of

cooling air.

8)

Restricked exhaust gas outlet.

9)

Engine detonating due to low octane gasoline

with

heavy load at low speed.

Carbon deposit in combustion space.

11-5

ENGINE KNOCKS

1)

Gasoline

of

poor

quality

or

low octane rating.

2)

Engine operating under heavy-load at

low

speed.

3)

Carbon

or

lead deposits

in

cylinder head.

4)

Incorrect spark timing.

5)

Lose

or

burnt out connecting rod be.aring.

6)

Worn

or

loose piston pin.

7)

Engine overheated.

11-6

ENGINE BACKFIRES THROUGH CARBURETOR

1)

Water

or

dirt in gasoline

or

poor grade

of

gasoline.

2)

Sticky intake valve.

3)

Overheated valves,

or

hot

carbon particles in engine.

4)

Engine cold.

-

40

-

12.

CHECKS

and

CORRECTIONS

After'dismantling and cleaning the engine parts,

check

them, and

if

necessary, correct them,

according

to

the correction table.

The

correction

table

applies whenever

the

engines

are

repaired. Its contents should

be

thoroughly understood by those

who

undertake the repairing. Its specifications must be abided

by to effect correct maintenance. Below,

terms

employed

in

the correction table

are

explained.

1)

CORRECTION

All operations performed on the engine parts

for

the purpose

of

improving

or

recovering

the

engine performance, consisting

of

repair, readjustment, and replacement.

2)

STANDARD SIZE

Design dimension

of

the part without the tolerance.

3)

CORRECTION TOLERANCE

Tolerance on the re-finished part dimension

or

on the readjustment dimension.

4)

CORRECTION LIMIT

Limit on

the

part and adjustment, beyond which any dimensional and functional change, due to

wear, burn and other causes

will

adversely affect

the

normal engine performance.

5)

USE LIMIT

Limit, beyond which the part

is

no longer usable, due to defects in function

or

strength.

NOTE:

All

dimensions in

the

"13.

CORRECTION TABLE"

are

given in millimeter, except where

otherwise specified.

-41

-

13.

CORRECTION TABLE

7

CORRECTION

METHOD

t

ITEM

Flatness

of

cylinder

head

ENGINE

MODEL

CORRECT1

STANDARD

TOLERANCE

SIZE

N

LIMIT

USE

"IT

REMARKS

TOOL

surface ,late, 'eeler

0.1

5

Correct EY25-2 EY27-2

M.018

EY 18-3 EY23 EY25-2 EY27-2

EY14 EY23

EY18-3

EY27-2

EY25-2

65

dia.

68

dia. 72 dia. 74 dia.

4.0.01

9

0

0.01

Bore

0.1

5

1.15

Roundness

Boring

EY14 EY18-3 EY23 0.01 5 EY25-2 EY27-2

EY14 EY 23

EY18-3 EY25-2

EY27-2

1.2-

1.5

EY14

N.015 6

dia.

EY18-3 EY23 EY25-2 EY27-2

7 dia. +0.036-+0.016

S.T.D.

61.963 dia.

EY14

C 62.463

dia.

B

62.213dia.

Cylindricity

Valve seat contact

width

Correct

2.5

0.1 5

0.15

9t

middle

>onion

Valve guide

I.D.

Replace

0.2

I

S.T.D.

64.980

dia.

EY18-3

I

B

64.230

dia.

~~ ~~

1

C 65.480 dia.

I

O.D.

at

skirt,

in

thrust

direction

(over

size)

EY23

S.T.D.

67.970 dia.

B

68.220dia.

C

68.470

dia.

-0.02

Micrometer

Vernier calipers

"0.1

Replace

-0.1

0.15

0.035

EY25-2

1

B

72.19dia.

I

S.T.3.71.94

dia.

C

72.44 dia.

S.T.D. 73.928

dia.

EY27-2

1

0

74.178dia.

EY25-2

y:p

l::

1

EY23 2nd

2.0

+O

.02

5

0

Width

of

ring

groove

0.15

Replace

EY18-3 Oil

+0.035

0

I

oil

2.8

I

Top

2.0

EY27-2 2nd

2.0

I

Oil 4.0

EY14 EY18-3

,

14 dia.

P.,"

+0.002

Cylinde gauge

Piston pin hole 0.035

Replace

--.-"I

-0.009

EY25-2 EY27-7

16dia.

I

-

"

-

I

EY14

I

0.037L-0.075L

Max. cylinder dia. and piston dia.

at

skirt in thrust direction

EY18-3

EY23

I

0.030L-0.069L

Cylinde Micro-

meter

gauge, Clearance between

piston and cylinde

0.025

Replace

EY25-2

0.072L-0.111

L

EY27-2

0

06

L-

0.099

L

-42

-

Clearance between EY27-2

piston ring and

ring groove

Fit between piston EY23

&

piston

Ring gap

Ring width

Piston

O.D.

I

Fl

1

I

lame end

I.D.

1.D.

I

Large end

Clearance between

rod

and cr& kpin

EY25-2 2nd

EY14

EY18-3 EY23

EY 14 EY 18-3 0.009T-0.010L

EY25-2 EY27-2

EY18-3 EY25-2 EY2722

EY25-2 EY27-2

EY14 EY 18-3

EY23 EY25-2

EY27-2 EY14 0.05L-0.076L

E??!-3

EY25-2

EY27-2

I

Top

Oil

2:

TOP

Oil

2nd

2

.a

14 dia.

I

16 dia

I I I

I

,

24 dia.

26 dia. +0.013

28

dia.

I

-~

0.050L-0.095L

0.040 L- 0.085 L

0.01OL-0.055L

0.050L-0.095L

0.04OL-0.085L

0.01OL-0.065L

0.004T- 0.01 5 L

0.20-0.40

rl

0.05-0.25

-0.05h -0.07

-0.04-

4.01--0.03 Top 2.5

-0.05-

-0.04-

-0.01-4.03

I

-0.060

-0.07

-0.06

0

4.008

-0.005

-0.01

~~

3

1

0

0.04L-0.066L

'

0.15L

0.06L

-0.1

-0.04

0.1

1

1.5

USE

I

L,MIT

-0.1

REMARKS

0.15

0.06L

1.5 Replace

o*2

1

TOOL

Feeler

ww

Cylinder gauge

Micrometer

Feeler gauge

Micrometer

Cylinder gauge

Micrometer

CORRECTION

METHOD

Replace

Small end

Clearance between 0.01 L-0.029L small

and piston

clearance

Parallelism between large end and

small end bores

Distance between large end and

small

end

I.D.

1.0.

bores

EY25-2 EY27-2

EY 18-3

EY14

'

EYf8-3

E

Y23 EY25-2 EY27-2

EY25-2 EY27-2

14 dia. i-o.021-+0.01

16 dia. M.027-+0.016

I

0.021 L-0.WOL L- 0.7

L

0.1

0.05

-0.1

-43

Cylinder gauge

Cylinder wage

Micrometer

Feeler

gauge

Test bar

&

Dial

indicatol

Replace

Replace 0.1

Remachine or Replace

Remachine

or

Replace

0.12

0.1

0.08

2

0.15

1

-

ITEM

Crankpin

Crankpin O.D. EY 23

roundness EY25-2

Crankpin O.D. EY23 cylindricity

Crankpin O.D. parallelism

O.D.

ENGINE STANDARD CORRECTION

1

MODEL

4

EY -1 EY 18-3

EY25-2

zi

I

EY14 EY18-3

EY27-2 EY14

I

EY18-3 EY25-2

I

EY*7-2

I

EY14 EY 18-3

EY25-2

1

EY23

I

EY27-2

1

SIZE

24 dia. -0.050-0.063 26 dia. -0.037-0.050

28

dia.

TOLERANCE

-0.040.-

0.053

I

LIMIT

0.15 0.15 EY27-2

1

I

below

0.005

I I I I

below 0.005

I

below

1

I

0.008

I

USE

LIMIT

?

EMAR KS

CORRECTION

I

METHOO

Micro- Remachine meter or Replace

Micrometer

Dial indicato

4

Crankshaft journal O.D.

Cam lobe height

Journal

O.D.

Squareness

-0.003-

EY25-2 EY27-2 Mag.

EY14 EY 18-3

EY25-2

1

EY23

EY14D EY 18-38 Drive

EY23B Mag.s. 17dia. "0.016--0.027

-1

EY18-3D Drive EY23D !Mag.

EY25-2B j Drive EY27-28 iMaq.

EY25-20 Drive EY27-2D Mag.

I

EY14

1

EY18-3

I

EY14 EY18-3

I

EY23

'

EY25-2 EY27-2

1

Drive

s.

3o

dia

s.

I

24.95

1

30.8

s.

22 dia. "0.003-"0.012

Drive Mag.

s.

15dia.

{:;e:'

I

I I

I

!Intake

1

15 dia. --0.016~--0.027

s.

25 dia. "0.003~-0.012

s.

l7

dia.

s.

30

dia.

s.

20 dia.

s.

15 dia.

s.

15

dia.

32

-

Exhaust

dia.

-0.003--0.012

-0.009-0

I

4.016-"0.027

-0.016~-0.027

1

-0.003--0.012

I I I

~o~032~~o~043

I

j

20.025,b -0.040

0.075~-0.095

4.01

fl.1

2

-0.05 -0.05

I

1

-0.25

'

]

0.05

I

'

0.05

I

j

-1-5

I

,

I

-0.25

I

0.05

I

1

I

i

l.o

I

1

i

~ ~~~

:or total ength

Micro-

meter

Micro-

meter

calipers

Square Replace

Replace

,-

Clearance between stem and guide

I

EY18-3

EY23 Intake EY25-2 Exhaust EY27-2

ilntake

/Exhaus7

I

0.025L-O.C)55L

0.075L-0.110L

1

0.056L-0.098L

-44

j

.

0.3

-

0.3

4t

middle

~

Cylinder Replace

ENGINE MODEL

I

CORRECTION

REMARKS

TOOL

CORRECTION

METHOD

STANDARD

SIZE LIMIT

USE

ITEM

TOLERANCE

0.10L-0.14L

0.16L-0.2OL

LIMIT

below

above

0.0:

0.25

EY14 EY 18-3

EY 23

Tappet clearance

Correct

E Y 25-2 EY27-2

EY14

2.5 0.04L-0.12L

EY18-3 FY23 Clearance between

groove and retainer

0.5

-2

.o

Correct

Replace

EY25-2 EY27-2

2.5

0.04L-0.15L

EY14

Venier calipers

Stem

end

length

4.0 -2

.o

EY27-2 EY 14

EY18-3 EY 23

38.12

46

0

-

+Q.06

Venier calipers

Total length

-0.5

Replace

E Y 25-2 EY27-2

50.9

20.05

EY14

Cylinder gauge

&

Micrometer

0.013L-0.037L

0.025L-0.062L

Clearance between

stem

and guide

EY18-3 EY23

EY27-2 EY

14

EY 23

EY 25-2

EY 18-3

0.2 0.2

Replace

Metering needle unscrew

Fixed EY25-2 EY27-2

f1f4

EY 14 EY18-3

EY 23

1

BV18 2 BV21

1

BV21 1-3B

Pilot screw unscrew

E Y 25-2 EY27-2

1-518

1-1/2 EY14

EY18-3

NGK

34HS

Spark plug

NG

K

BP4HS

EY14 EY 18-3

Adjust or Replace

Spark gap

EY23

-

EY25-2 EY27-2

0.6-

0.7

1

EY 14 EY 183

2

5O

Timing tester

Spark timing EY23

EY27-2

EY25-2

23' before T.D.C.

Adjust

0.4

EY14 EY 18-3

EY25-2 EY27-2

kO.1

20.05

Contact breaker spanner

Point opening

50.1

Adjust

0.35

-

45

-

ITEM

Max.

Output

Continuous Rated output

MODEL

EY14D EY183D

EY23D EY25-2D EY27-2D EY14D EY18-3D EY23D EY25-2D EY27-2D

HPIrpm

3.5l4.000

5.0/4,000

6.014,OOO

7.014,000

7.514.000

2.513.600

3.513.600

4.513.600

5.013.600

5.513.600

CORRECTION LIMIT

Below 110%

of

rated output

REMARKS

,”.

ITEM

Fuel Consumption

ITEM

Lubricant Consumption

ITEM

Special Lubricant Quality

MODEL

EY14 EY 18-3

EY25-2 EY27-2

MODEL

EY14 EY 18-3 EY23 50 15 EY25-2

”-

EY27-2

MODEL

EY14

’

EYl8-3

E

Y23 EY25-2 EY27-2

,

literlhr

.o

1

1.5

1.9 EY23

2.2

2.3

ahr

15

28 30

liter

0.50

0.70

0.65

0.85

REMARKS

USE

LIMIT

cc/hr

REMARKS

50

50 15

-

60

REMARKS

or

Use the class SC

Below

-1OOC (14’F) SAE 1OW-30

-1OOC (14OF) -2OoC I68OF) SAE 2OoC

/6S0F)

nigher grade Engine Oil

-4OOC (104OF)

SA€

#20

#30

ITEM

Oil Change First

I

EY14

MODEL

I

1

FREQUENCY

Time:

Change

oil

Second Time and Thereafter: Change

after 20 hours operation.

-46

-

oil

OF

every

OIL

50

CHANGING

hours

operation.

I

ITEM

I

MODEL I kg/ud/rpm

I

CORRECTION LIMIT

I

TOOL

EY 14 4.61420 EY 18-3 5.91360

Cylinder Pressure EY23 6.7

1380

70%

of

normal value EY25-2 5.51420 EY27-2 5.51420

Pressure gauge

ITEM MODEL

TOOL REMARKS

EY 14D EY183D EY23D EY25-2D

1,200- 1,300

EY27-2D

Min.

accelerating

revolution

Tachometer

EY14B EY23B

EY 18-38 EY25-2B

EY27-2B

600-

650

ITEM MODEL

1

kg-crn

I

ft-ib

1

TOOL

I

REMARKS

Cylinder head clamp

nuts

EY14 190- 230 13.7- 16.6

EY18-3

EY23

1

330-360

I

23.8-25.9

I

Torquewrench

I

EY25-2 EY27-2

340-370

I

24.6-26.7

I

EY14

I

90-115

1

6.5-8.3

I

EY

18-3

EY23

170- 200

I

12.3-14.4

1

Torque wrench

Connecting rod

2

bolts

P

I-

I

EY27-2

1

200-250

1

14.4- 18.0

1

F

:Lz-

nuts

EY14

I

450-500

I

32.6-36.1

I

EY18-3 EY23

EY 27-2

EY25-2

43.5-47.0

Torque wrench

600-

650

EY14

I

80-100

I

5.8-7.2

I

Main bearing cover

bolts

EYl8-3

1

170- 190

12.3- 13.7

Torque wrench

EY25-2

EY14

I

250-290

I

I I

230-270

Spark plug

I

EY25-2 EY27-2

260- 300 18.8-21.7

-47

-

14.

MAINTENANCE

and

STORING

The following maintenance jobs apply when the engine is operated correctly under normal

conditions.

The

indicated maintenance intervals are by no means guarantees

for

maintenance

free operations during these intervals.

For

example, if

the

engine is operated in extremely dusty conditions, the

air

cleaner should be

cleaned every day, instead of every

50

hours.

n

14-1

DAILY CHECKS

and

MAINTENANCE (EVERY

8

HOURS)

Checks and maintenance

Reasons for requiring them

Remove dust from whatever parts which

ceptible

to

dust.

accumulated dust.

The

governor linkage is especially sus-

Check

external fuel

leakage.

If

any, re-

tighten

or

replace.

Not

only wasteful but

also

dangerous

Check

screw tightening. If any

loose

one

vibration accidents.

is

found, re-tighten.

Loose screws and nuts

will

result in

as

necessary.

I

ficient oil, it

will

fail.

If

the

engine

is

operated without suf-

Check oil level in crankcase and

add

up

14-2 EVERY

20

HOURS CHECKS and MAINTENANCE

Checks and maintenance

Reasons for requiring

them

-\

Change crankcase oil.

To

remove run-in wear particles.

14-3

EVERY

50

HOURS

(10

DAY) CHECKS and MAINTENANCE

Checks and maintenance

!

I

Reasons for requiring them

Change crankcase oil.

Contaminated

oil

accelerates

wear.

Clean air cleaner

Clogged air cleaner harms engine opera-

tion.

-

Check spark plug.

If

contaminated,

wash

made difficult.

in

gasoline or polish with emery paper.

Output power is reduced and starting

is

,

14-4 EVERY

100

-

200

HOURS (MONTHLY) CHECKS and MAINTENANCE

I

Checks and maintenance

i

I

Reasons for requiring them

””

Clean

fuel

filter and

fuel

tank. =engine will

be

out

of

wder.

Clean contact breaker points.

The engine output drops.

_”

”

-

48

-

14-5

EVERY

500

-600

HOURS (SEMIANUAL) CHECKS

and

MAINTENANCE

Remove cylinder deposit.

Disassemble and clean carburetor.

14-6 ~ EVERY

Perform overhauls, clean

replace parts.

Change piston rings

Replace fuel pipe once

14-7

1)

PREPARATION

Perform

the

Checks

1000

Checks

above

and maintenance

head

and remove carbon

HOURS (YEARLY) CHECKS

and maintenance

correct

a

year.

for

LONG-TERM STORAGE

13-1

and

13-2

or

maintenance

Reasons

The

engine will

and

MAINTENANCE

Reasons

The engine output

of

order.

To

prevent-

fuel

leakage.

jobs.

for

requiring them

be

out of order.

for

requiring them

drops

from

danger caused by the

and become out

>

2)

Drain fuel from

3)

To

prevent rust in

the

fuel tank and carburetor

the

cylinder bore, apply oil through

crankshaft several turns by hand. Re-install

4)

Turn

the

starting pulley by hand and leave it where

5)

Clean

6)

Put a vinyl

the

engine outside with oiled cloth.

or

other cover over

the

engine and

float

the

store

chamber.

plug.

the

resistance

the

spark plug

is

the

hole

heaviest.

engine in dry place.

and turn

the

-49

-

Industrial

Engines