Robin EH17-2, EH25-2 Service Manual

CONTENTS

Section Title

1

.

2

.

3

.

4

.

5

.

6

.

7

.

8

.

Page

4-1 4-2 4-3

4-4

4-5 4-6 4-7 4-8 4-9 4-1

0

4-1

1

4-1

2

4-1 3 4-1 4 4-1

5

4-1 6 4-1 7

I.

SPECIFICATIONS

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

Model

EH12-2B

EH

12-2

EHl2-2D EH12-2BS

EH12-2DS

TY

Pe

X

Bore Piston Displacement

Max.

Nem (kaf*m)/rDm

I

Direction Cooling system Valve Arrangement

Lubrication Lubricant Capacity of Lubricant

I

Carburetor

Stroke

Torque

of

Rotation

~~ ~ ~~~~~ ~~ ~

Air-Cooled, 4-Cycle, Single-Cylinder, Horizontal

x

43 rnm (2.36 x 1.57 in.)

60

cm3

(7.38 cu.in.)

As

Viewd From

Splash Type

L

(0.16

U.S.

I

52)

15 (1

Counterclockwise

~~ ~

Automobile

/1300

Oil

SAE

121

Forced Air Cooling

Overhead Valve

#20, #30 or 1 OW-30 ; Class SE, SF

0.6

Horizontal Draft, Float Type

P.T.O.

gal.)

Shaft, Gasoline Engine

7.5 (0.76) /2600 Shaft Side

or

higher

I

Fuel

I

Fuel Feed System Fuel Tank Capacity

I

Spark Plug Charging Capacity

I

Speed Reduction Governor System

Dry

Weight

Length

I

310 g/KW*h (230 gr/HP*h) At Continuous Rated Output

~~~~~~~ ~~

I

-

Recoil Starter Starting System

2:l Cam Shaft Drive

15.5 kg (34.2Ib.)

299 mm (1 1.77 in.)

Recoil and Electric

Starter

I

18.0 kg (39.7 Ib.)

I

299 mm (1 1.77 in.) I 297 mm (1 1.69 in.) I 297 mm(ll.69 in.)

Automobile Gasoline

~ ~~~

Gravity Type

U.S.

3.6 L (0.95

Flywheel Magneto (Solid State) Ignition System

NGK BGES

12V - 1.3A

Centrifugal Flyweight System

gal.)

-

Recoil

I

15.0 kg (33.1 Ib.)

330mrn (12.99in.) 366 mm (14.41 in.)

Starter

12V

Starter

Recoil and Electric

I

17.5 kg (38.6Ib.)

341 mm (13.43in.) 366 mm (14.41 in.)

-

1.3A

-1-

Model

EH17-2B

EH17-2BS

EH17-2

EH17-2D

EH17-2DS

TY

Pe

X

Bore

Compression Ratio 8.5

Output

Kw

Max.

Nom

Direction of Rotation

I

Cooling system

I

Valve Arrangement

I

Lubrication Lubricant

Capacity of Lubricant

Stroke

(HP)/rpm

Torque

(kgf*m)/rpm

Continuous Max.

~ ~~ ~~ ~

Air-Cooled, 4-Cycle, Single-Cylinder, Horizontal

~~ ~~

(3.5)

2.6

I I

I

Automobile Oil

~~ ~~~~ ~ ~

67

/

1500 2.9 (4.0) / 1800

4.4 (6.0) /2000

21.4 (2.1 8) Counterclockwise

/

1300

~~~~~~~ ~

SAE

#20, #30

Horizontal Draft, Float Type Carburetor

x

49

mrn

172 cm3 (10.50 cu.in.)

As

Viewd From P.T.O. Shaft Side

Forced

~~

Overhead Valve

Splash Type

L

0.65

(0.17

P.T.O.

(2.64

X

1.93 in.)

2.6

Air

Cooling

~_____

or

1OW-30 ; Class

U.S.

gal.)

Shaft, Gasoline Engine

.

(3.5)

/3000 2.9 (4.0) /3600

4.4 (6.0) /4000

1

0.7

(1

-09) / 2600

_____

~ ~

SE,

SF

or higher

Fuel Fuel Consumption Rate Fuel Feed System Fuel Tank Capacity

Spark

Charging Capacity

I

Starting System Speed Reduction

Plug

Dry

Weight

Dimensions

Length

Width

Height 380mm (14.96in.)

310g/KW-h (230 gr/HP*h) At Continuous Rated Output

-

2:l

Cam Shaft Drive

16.5 kg (36.4 Ib.)

mm

(1 1.85 in.) (12.99in.)

301

Automobile Gasoline

Gravity Type

3.6 L (0.95

Flywheel Magneto (Solid State)

12V - 1.3A

NGK

US.

B6HS

gal.)

-

Centrifugal Flyweight System Governor System

19.0

kg (41.9

mrn

341

rnrn

380rnm (14.96in.) 380mm (14.96in.)

Ib.)

(1

1.85 in.)

(13.43in.) 330

16.0 kg (35.3

299

mm

rnm

330

Ib.)

(1 1.77 in.) 301 (12.99in.)

18.5 kg

299 mm(ll.77in.)

341 380rnm (14.96in.:

12V

rnm

-

1.3A

(40.8

Ib.)

(13.43in.:

-2-

Model

EH25-2

6

EH25-26s

EH25-2

~~~~~~ ~~ ~

EH25-2D

EH25-2DS

TY

Pe

x

Bore Piston Displacement Compression Ratio

output

Kw

Max.

Nom (kgf*m)/rpm Direction

Cooling system

Valve Arrangement

Lubrication

Capacity of Lubricant Carburetor

Fuel

Stroke

(HP)hm

Torque

of

Rotation

Continuous Max.

Air-Cooled, 4-Cycle, Single-Cylinder, Horizontal P.T.O. Shaft, Gasoline Engine

75 X 57

mm

(2.95

251

cm3 (15.31 cu.in;)

X

2.24 in.)

8.5

(5.5)

/3000 4.7 (6.4) /3600

(8.5)

SE,

SF

/4000

/

2600

or

higher Lubricant

6.3

16.6 (1.69)

I

4.0

(5.5)

I1

500

4.7 (6.4) / 1800

(8.5)

6.3

33.1 (3.38)

Automobile Oil SAE #20, #30 or

/2000

/

1300

Counterclockwise As Viewd From P.T.O. Shaft Side

Horizontal Draft, Float Type

4.0

Forced Air Cooling

Overhead Valve

Splash Type

1

OW-30 ; Class

1

.O

L

(0.26

U.S.

gal.)

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

Automobile Gasoline Fuel Consumption Fuel Feed System Fuel Tank Capacity Ignition System Spark Plug Charging Capacity

Starting System Recoil Starter Speed Reduction

Governor System Dry Weight

Dimensions

Rate

I

Length

Width

Height

31

-

I

2:l Cam Shaft Drive

I

24.0 kg (52.9

333mm (13.11 in.) 380mm (14.96in.)

440mm

Ib.)

(17.32in.)

0

g/KW*h (230 gr

6.0

Flywheel Magneto (Solid State)

12V - 1.3A

Recoil and Electric

Starter

Centrifugal Flyweight System

28.0 kg (61.7 Ib.) 333mm (13.11 in.) 380mm

440mm

(14.96in.) (17.32in.)

/

HP-h)

At Continuous Rated Output

Gravity Type

L

(1

59

U.S.

NGK

B6HS

I

Recoil

23.0

gal.)

kg

-

Starter

(50.7

Ib.)

~~~ ~~

-

12V

1

Starter

Recoil and Electric

1.3A

-

27.0 kg (59.5

332mm(l3.07in.) 332mm (13.07in.)

380mrn (14.96in.) 380mm (14.96in.)

440mm

(17.32in.) 440mm (17.32in.)

Ib.)

-3-

2-1

MAXIMUM OUTPUT

The maximum output is the output of an engine with its throttle valve fully opened under the condition that all the moving parts are properly

A

new engine may not produce full maximum output while its moving parts are still not broken-in.

2-2

CONTINUOUS

RATED

OUTPUT

worn

in after the initial break-in period.

The continuous rated output is the output

favorable from the view point

is

When the engine

installed

of

engine’s life and fuel consumption.

on

a certain equipment,

of

an engine at optimum governed speed which is most

it

is

recommended that the continuous output

required from the engine be kept below this continuous rated output.

2-3

MAXIMUM

The maximum torque

TORQUE

is

the torque at the output shaft when the engine is producing maximum output at

certain revolution.

-4-

2-4

PERFORMANCE CURVES

8

0

EHlPD,

B

HP

4

3

kW

2

for

B

type

+

3

l2

n

+

3

0

1

0

1

2000

(1

000)

REVOLUTION

3000

(1

500)

-

r.p.m.

4000

(2000)

-5-

0

EH17D,

6

for

B

tvDe

N.m

kgfam

(1

000)

REVOLUTION

3000

(1

500)

-

-6-

4000

(2000)

r.p.m.

EH25D,

B

kW

HP

-6

8

7

I

t:

$4

I-

&

5

4

r

"

I

I I

"

I

MAXIMUM

I

MAXIMUM

I

"-

I

TORQUE

I

HORSEPOWER

RECOMMENDED

1

AL\

I I

'(NET)

I

16.5

15.5

14.5

N.m

(33)

(31)

(29)

c

kgf-m

1.7

(3.4)

1.6

(3.2)

1.5

(3.0)

1.4 (2.8)

2

1

0

2000

(1

000)

I

i

REVOLUTION

3000

(1

500)

-

-7-

'

r.p.m.

4000

(2000)

3.

FEATURES

1.

The overhead valve design offers

a

compactness, light weight and ideal combustion characteristics

resulting in more power from Iess fuel and prolonged engine life.

2.

An

optimum lubrication and better tilted operation thanks to upright cylinder design.

3.

A crossflow arrangement

of

intake and exhaust ports ensures stable performance under high ambient

temperature.

4.

The automatic decompressiom system lightens conventional

5.

An easy operation thanks to integrated engine control system. Improved throttle mechanism

6.

Combustion and mechanical noises have been analyzed acoustically and improved for better tonal

SV

engines.

is

adopted for easy starting.

the

recoil pull force by

40%

quality and lower engine noise.

7.

Optimally designed reciprocating parts reduce the vibration level of the engine. equips single through-balancer shaft as an option.

4.

GENERAL DESCRIPTION

4-1

CYLINDER

AND

CRANKCASE

OF

ENGINE COMPONENTS

comparing to the

EH25-2

engine

,

The cylinder and crankcase

is

single piece aluminum diecasting. The cylinder liner, made of special cast iron,

is

molded into the aluminum casting.

The crankcase has a mounting surface. on the output

shaft side, where the main bearing cover is attached.

4-2

MAIN

The main bearing cover which

BEARING

is

mounted on the output shaft side of the

COVER

is

an aluminum diecasting,

crankcase. Remove the main bearing cover to inspect the inside

of

the engine. The pilots and bosses are machined on the cover for direct mounting of the engine onto such machines

as

generators and pumps.

Oil gauge (fillers) are on both sides of the cover for easy maintenance.

Fig.

/"-

\

4-1

/"

-8-

OIL GAUGE

Fig.

4-2

OIL

GAUGE

4-3

CRANKSHAFT

The crankshaft is forged carbon steel, and

W

pin is induction-hardened.

the

crank

B

TYPE

The output end of the shaft has a crankshaft gear, and balancer gear for

EH25-2

which are pressed into

position.

D

TYPE

Fig.

4-3

44

CONNECTING

ROD

AND

PISTON

The connecting rod is an aluminum alloy diecasting,

and

its

large and smalI ends function as bearings. The piston two compression rings and one

is

an aluminum alloy casting, and carries

oil

ring.

4-5

PISTON RINGS

The piston rings are made The profile of the top ring second ring has a tapered The

oil

ring consists

of

special cast iron.

is

barrel face and the

face.

of

a cutter ring and a

coil

expander for better sealing and less oil consumption.

-9-

I

fig.

4-4

TOP

RING

fig.

SECOND

OIL

4-5

RING

4-6

CAMSHAFT

The camshaft

for

the D-type engine is made

of

special cast iron and camshaft gears are casted to-

gether

in

one piece. Both sides of the shaft fit into the plane bearings on the crankcase and main bearing cover. The camshaft for the B-type engine is made of forged carbon steel and also functions as PTO shaft. The cam gear bearings are employed

is

press fitted on the shaft and the ball

on

both sides for supporting

the shaft.

4-7

VALVE ARRANGEMENT

The intake valve is located

on

flywheel side

of

the

cylinder head. The hard alloy valve seats axe molded in the cylinder head and stellite is fused to the exhaust valve face. The cylinder baffle leads cooling air to the exhaust valve area for the optimum cooling.

B

Fig.

TYPE

4-6

n

D

lYPE

INTAKE

/

4-8

CYLINDER HEAD

The cylinder head is an aluminum die casting which

utilizes wedge

type

combustion chamber

for

the

highest combustion efficiency.

-

10

Fig.

4-7

Fig.

4-8

-

4-9

GOVERNOR SYSTEM

The governor

is

a centrifugal flyweight type which ensures constant operation at the selected speed against load variations. The governor gear with governor weights is installed

on the main bearing cover.

4-10

COOLING SYSTEM

The large fins on the flywheel provide sufficient cooling air capacity

for

the inlet and exhaust area and cylinder. The cylinder baffle helps the cooling air flow efficiently.

4-1

1

LUBRICATION

All the rotating and sliding parts are splashlubricated by the oil scraper on the connecting rod.

/

GOVERNOR

GEAR

Fig.

4-9

4-1

2

-IGNITION SYSTEM

The ignition system is a transistor controlled magneto ignition system which cosists of a flywheel and an ignition coil with a built in transistor. This system has an ignition timing advance for easy starting.

-

11

-

I

OIL

SCRAPER

Fig.

4-10

4-1

7

4-13

The engines are equipped with a horizontal draft carburetor that has a float controlled fuel system and a The carburetors are calibrated carefully for easy starting, good acceleration, low fuel consumption and sufficient output.

CARBURETOR

fixed

main jet.

4-14

The air cleaner is a element type is available.

AIR

CLEANER

single

CLEANER CASE

Single

4-15

Unbalanced inertia force which rotates at the same speed with the crankshaft to effectively reduce vibration.

BALANCER

(Option

urethane foam element system.

element type

Fig.

4-

1

3-

I

for

EH25-2)

is

balanced by the balancer

As

an option, heavy duty type with

Double element type

Fig.

4-

13-2

BALANCER

a

CLEANER COVER

I

double

-

12-

Fig.

4-14

4-16

DECOMPRESSION

An

automatic decompression mechanism which

SYSTEM

opens exhaust valve before the piston reaches compression top

is

assembled on the camshaft for easy

starting.

AUTOMATIC

DECOMPRESSOR

Fig.

4-14

SYSTEM

-

13-

4-1

7

SECTIONAL

VIEW

OF

ENGINE

FUEL

TANK

FLYWHEEL

-

14-

MAIN

BEARING

COVER

a

ROCKER

ARM

PUSH ROD

-

15

-

5.

DISASSEMBLY

5-1

PREPARATIONS AND SUGGESTIONS

1)

When disassembling the engine, memorize the locations

reassembed correctly. If yor are uncertain

AND

REASSEMBLY

of

identifying some parts, it

of

attached to them.

2)

Have boxes ready to keep disassembed parts by group.

3)

To

prevent losing and misplacing, temporarily assemble each group

4)

Carefully handle disassembed parts, and clean them with washing oil

5)

Use

the correct tools in the correct way.

5-2

SPECIAL

Tool

TOOLS

No.

Tool

individual parts

is

of

disassembed parts.

if

necessary.

Use

so

that they can be

suggested that tags be

209

Market

-

95004-

parts

07

Flywheel

Flywheel puller

FLYWHEEL PULLER

puller with

bolt

For For

pulling

off

FLYWHEEL

the flywheel the flywheel

PULLER

EH25-2

EH12-2,

EH17-2

/"-

Fig.

-

16

5-1

-

5-3

DISASSEMBLY PROCEDURES

Step

1

Part

to

remove

(1)

Remove

(2)

To

gauge.

oil

drain

plug

and drain oil. Oil drain

discharge oil quickly, remove oil

Remarks Procedures

Be careful gasket.

not

to

lose the

14mm

Tool

box

I

wrench

Fig. 5-2

-

17

-

GASKET

I

DRAIN

PLUG

Step

2

Part

Fuel

to

remove

tank

Procedures

1

(1)

Close

fuel

valve.

(2) Disconnect fuel hose between fuel strainer

and carburetor.

(3)

Remove fuel M6X14mm bolt M8X20mm bolt

tank

from cylinder

*.--

0-

head.

4pcs. (EH12-2,17-2) 4pcs. (EH25-2)

~ ~ ~~ ~~

Wipe

Remarks

off

spilt

thoroughly.

fuel

1

Omm

socket

Tool

(1

2mm)

wrench

I

(EH12-2,

(EH25-2)

FUEL

HOSE

17-2)

-

-*

Fig.

18

5-3

-

Step

I

Part

to

remove

I

Procedures

I

Remarks

I

Tool

Recoil starter

housing

I

5

Oil sensor (Option)

I

(1)

Remove recoil M6

X

8mm

(1)

Remove blower housing

M6X

i2mm

(1)

Remove oil sensor probe. to damage stick and sensor since these are sensitive and

result.

from

blower housing.

flange

bolt

-

4pcs.

from

crankcase.

flange bolt 4pcs.

Be

an

erratic operation

careful not

may

BLOWER

1

Omm

lOmm

HOUSING

box

wrench

Fig.

-

19

5-4

-

)art

to remove

Procedures

Remarks

Tool

Muffler cover, Muffler and Exhaust pipe cover

(1) Remove muffler cover

cover.

M6X

lOmm flange

(2) Remove

cylinder head. M8 nut 2pcs. M6 (EHl2-2,17-2)

M8X

muffler

X

12mm

flange bolt

16mm flange

and

bolt

from crankcase and

bolt

exhaust pipe

0..

Spcs.

-

1

PC.

-

1 pc.

(EH25-2)

I

Be careful muffler gasket.

not

to

8mm, lOmm

lose

12mm socket wrench

and

M8

NUT

:

2

pcs.

MUFFLER

c

COVER

Fig.

-

20.-

5-5

Procedures

Remarks

Tool

Control

box

and Electric (Option)

(1)

Disconnect wires. blue light blue black

(2)

Remove black wires from electric starter.

(3)

Remove control

(4)

Loosen

1

(diode rectifier

***

1

two

)

1

(diode rectifier

(magnetic switch)

box.

bolts

and

remove electric

)

starter.

M8

bolt 2pcs.

Fastened together with fuel

tank.

12mm socket wrench

to

-

21

-