Robin EH09 Service Manual

SERVICE MANUAL

Models

EH09, EH12-2 Rammer ENGINES

PUB-ES1330 Rev. 12/01

4-16 SECTIONAL VIEW OF ENGINE

EH09D

INTAKE VALVE

EXHAUST VALVE

MUFFLER

PISTON

PISTON RING

CYLINDER HEAD

PISTON PIN

IGNITION COIL

BLOWER HOUSING

RECOIL STARTER

P.T.O. SHAFT

MAIN BEARING COVER

ADAPTER (

FLANGE

)

FLYWHEEL

CRANKCASE

Fig. 4-15

-

12

-

ROCKER COVER

PUSH ROD

ROCKER ARM

SPARK PLUG

CONNECTING ROD

CARBURETOR

AIR CLEANER

TAPPET

CAMSHAFT

GOVERNOR LEVER

SPEED CONTROL

LEVER

OIL GAUGE

PLUG

Fig. 4-16

-

13

-

CRANKSHAFT

STIFFENER

EH12-2D

INTAKE VALVE

EXHAUST VALVE

PISTON

PISTON RING

P.T.O. SHAFT

CYLINDER HEAD

IGNITION COIL

BLOWER HOUSING

PISTON PIN

MAIN BEARING COVER

CRANKCASE

Fig. 4-17

-

14

-

RECOIL STARTER

FLYWHEEL

ROCKER COVER

PUSH ROD

ROCKER ARM

SPARK PLUG

MUFFLER

CONNECTING ROD

CARBURETOR

AIR CLEANER

TAPPET

GOVERNOR

LEVER

CAMSHAFT

OIL GAUGE

CRANKSHAFT

Fig. 4-18

-

15

-

SPEED CONTROL

LEVER

PLUG

5. DISASSEMBLY AND REASSEMBLY

5-1 PREPARATIONS AND SUGGESTIONS

1) When disassembling the engine, memorize the locations of individual parts so that they can be reassembled correctly. If you are uncertain of identifying some parts, it is suggested that tags be attached to them.

2) Have boxes ready to keep disassembled parts by group.

3) To prevent losing and misplacing, temporarily assemble each group of disassembled parts.

4) Carefully handle disassembled parts, and clean them with washing oil if necessary.

5) Use the correct tools in the correct way.

5-2 SPECIAL TOOLS (EH12-2D)

.oNlooTlooTesU

straptekraMrellupleehwylFleehwylfehtffognilluproF

FLYWHEEL PULLER

Fig. 5-1

-

16

-

5-3 DISASSEMBLY PROCEDURES

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2

EH09D

M8 NUT : 4 pcs.

OIL LEVEL GAUGE

M8 WASHER : 4 pcs.

reneffitSdnaretpadA

GASKET

.scp4:52x8M .scp2:03x8M ,rehsaw,tun8M

:rehsawgnirps

scp4

STEP 1

OIL DRAIN PLUG

GASKET

M8 SPRING WASHER : 4 pcs.

ADAPTER

STEP 2

M8 x 30 BOLT AND WASHER : 2 pcs.

STIFFENER

M8 x 25 BOLT AND WASHER : 4 pcs.

-

17

-

Fig. 5-2

petSevomerotstraPserudecorpdnaskrameRsrenetsaF

3retratslioceR

.scp3;21x6M

)D90HE(

.scp4;8x6M

)D2-21HE(

4gnisuohrewolB

EH09D

STEP 4

M6 x 8 FLANGE BOLT

BLOWER GUIDE CP

M4 TAPPING SCREW : 2 pcs.

STOP SWITCH

CLAMP

: 1 pce.

M6 x 12 FLANGE

BOLT : 1 pce.

M6 x 12 FLANGE BOLT : 1 pce.

M6 x 12 FLANGE BOLT : 2 pcs.

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.esacknarcmorfgnisuohrewolbevomer

STEP 3

M6 x 12 FLANGE BOLT: 1 pce.

.scp5;21x6M

)D90HE(

.scp2;8x6M

)D90HE(

.scp4;55x6M

)D2-21HE(

EH12-2D

STEP 4

CLAMP

M4 TAPPING SCREW : 2 pcs.

STOP SWITCH

M6 x 8 FLANGE BOLT: 1 pce.

BLOWER HOUSING CP

M6 x 8 FLANGE BOLT : 4 pcs.

STEP 3

M6 x 55 FLANGE BOLT : 4 pcs.

BLOWER HOUSING CP

Fig. 5-3

-

18

-

EH09D

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8roterubraC

9

ronrevogevomerdnatlobehtnesooL)1(

.ecp1;52x6M

.revel

ronrevogmorfgnirpsronrevogkoohnU)2(

.revel

ronrevogehthcihwnoelohehtkraM

.dekoohsignirps

gnikoohnuylluferacroterubracevomeR

ronrevogmorfgnirpsdordnadorronrevog

.revel

;tlobtovip6M

dnarevellortnocdeepS

etalpesab

.ecp1

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.scp2;tlob

M6 x 8 FLANGE BOLT : 2 pcs.

SPACER

SPEED CONTROL LEVER AY

STEP 9

BASE PLATE CP

M6 BOLT AND WASHER AY : 1 pce.

RETURN SPRING

ROD SPRING

GOVERNOR LEVER

FRICTION WASHER

INSULATOR

GOVERNOR ROD

GOVERNOR SPRING

M6 PIVOT BOLT

: 1 pce.

GASKET (INSULATOR

CARBURETOR

STEP 8

STEP 7

)

Fig. 5-6

-

21

-

EH12-2D

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7revelronrevoG

8

9

epip

GASKET

.rotcetorpehtevomeR)1(

.ecp1;61x8M

.ecp1;41x6M

ronrevogevomerdnatlobehtnesooL)2(

.ecp1;03x6M

.revel

ronrevogmorfgnirpsronrevogkoohnU)3(

.revel

ronrevogehthcihwnoelohehtkraM

.dekoohsignirps

ekatnidnaroterubraC

ronrevogmorfgnirpsdordnadorronrevog

gnikoohnuylluferacroterubracevomeR

.scp2;tun6M

.ecp1;04x6M

.revel

;tlobtovip6M

dnarevellortnocdeepS

tekcarberiw

.ecp1

egnalf41x6M

.scp1;tlob

M6 NUT : 2 pcs.

M6 x 40 BOLT AND WASHER : 1 pce.

STEP 8

INTAKE PIPE

INSULATOR

CARBURETOR

STEP 9

WIRE BRACKET

ROD SPRING

GOVERNOR

LEVER

STEP 7

M6 BOLT AND WASHER AY : 1 pce.

M6 x14 FLANGE BOLT : 1 pce.

Fig. 5-7

-

GOVERNOR ROD

GOVERNOR SPRING

NUT

22

-

GASKET (

INSULATOR

M6 PIVOT BOLT : 1 pce.

)

STEP 9

SPEED CONTROL LEVER

M6 x 12 FLANGE BOLT : 1 pce.

PROTECTOR

M8 x 16 BOLT AND WASHER AY : 1 pce.

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EH09D

)2(

EH12-2D

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).9-5.giF

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).01-5.giFeeS(

.rellupleehwylfehtgnisuleehwylfevomeR

).11-5.giFeeS(

.tfahsknarcmorfyekehtevomeR)3().21-5.giFeeS(

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)D2-21HE(SE6RB,SE6B:KGN

rehsaw

.scp2;52x6M

gnirps,tun21M

gnirps,tun41M

ALUMINUM BAR

Fig. 5-9 Fig. 5-10 Fig. 5-11

SPARK PLUG CAP

SPARK PLUG

STEP 12

IGNITION COIL CP

STEP 10

M6 x 25 BOLT AND WASHER AY : 2 pcs.

FLYWHEEL CP

M12 SPRING WASHER : 1 pce. (EH09D) M14 SPRING WASHER : 1 pce. (EH12-2D)

STARTING

PULLEY

M12 NUT : 1 pce. (EH09D) M14 NUT : 1 pce. (EH12-2D)

STEP 11

WOODRUFF KEY

Fig. 5-8

-

23

Fig. 5-12

-

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EH09D EH12-2D

M6 x 60 BOLT AND WASHER AY : 4 pcs.

M8 x 55 FLANGE BOLT : 4 pcs.

STEP 13 STEP 13

ROCKER COVER

M6 x 40 FLANGE BOLT : 4 pcs.

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.scp4;06x6M

)D90HE(

.scp4;04x6M

)D2-21HE(

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.scp4;55x8M

)D90HE(

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.scp4;56x8M

)D2-21HE(

ROCKER COVER

GASKET

CYLINDER HEAD CP

STEP 14

GASKET

PUSH ROD

M8 x 65 FLANGE BOLT : 4 pcs.

CYLINDER HEAD CP

Fig. 5-13

GASKET

SPACER (

BREATHER

GASKET

STEP 14

PUSH ROD

)

-

24

-

STEP 15

M6 x 30 BOLT AND WASHER AY : 9 pcs.

MAIN BEARING COVER CP

M8 x 16 FLANGE BOLT : 2 pcs.

SUPPORT (

MAIN BEARING COVER

STEP 15

MAIN BEARING COVER CP

M6 x 30 BOLT AND WASHER AY : 8 pcs.

)

-

25

-

GASKET (

BREATHER COVER

BRACKET (

MAIN BEARING

COVER

M6 x 16 FLANGE BOLT : 2 pcs.

M8 x 16 FLANGE BOLT : 1 pce.

)

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STEP 18

CRANKSHAFT

Fig. 5-19

Fig. 5-20

-

28

-

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STEP 19

BOLT (PIVOT) : 2 pcs.

ROCKER ARM

COLLET

Fig. 5-22

SPRING RETAINER

VALVE SPRING

EXHAUST VALVE

M6 NUT : 2 pcs.

GUIDE PLATE

INTAKE VALVE

Fig. 5-21

-

29

-

5-4 REASSEMBLY PROCEDURES

● PRECAUTIONS FOR REASSEMBLY

1) Clean parts thoroughly before reassembly.

Pay close attention to the cleanliness of piston, cylinder, crankshaft, connecting rod and bearings.

2) Scrape off all carbon deposits from cylinder head, piston top and piston ring grooves.

3) Check lip of oil seals. Replace oil seal if the lip is damaged. Apply oil to the lip before reassembly.

4) Replace all the gaskets with new ones.

5) Replace keys, pins, bolts, nuts, etc., if necessary.

6) Torque bolts and nuts to specification refer to the "TORQUE SPECIFICATIONS" (See page 76).

7) Apply oil to rotating and sliding portions.

8) Check and adjust clearances and end plays where specified in this manual.

5-4-1 CRANKSHAFT

(1) Install crankshaft in crankcase wrapping the

keyway with pol y viny l ta pe to av oi d dam age to oil seal.

(2) Install woodruff key for flywheel on crankshaft.

CRANKSHAFT

5-4-2 PISTON AND PISTON RINGS

(1) Install oil ring first, then second ring and top

ring. Spread ring only far enough to slip over pis-

ton and into correct groove. Use care not to distort ring.

Install second ring with punch ed mark bes ide the gap face upward. (See Fig. 5-26a, 26b)

POLYVINYL TAPE

Fig. 5-23

OPEN ENDS OF PISTON RING

Fig. 5-24

-

30

-

①

TOP

1

RING

EH09D EH12-2D

BARREL

MARK "RN"

② ③

2

3

Fig. 5-25

SECOND RING

OIL RING

MARK "R"

EH09D

EH12-2D

EH09D

EH12-2D

TAPER

TAPER UNDER CUT

CUTTER

CUTTER RING WITH COIL EXPANDER

RING

Model: EH09D Model: EH12-2D

Fig. 5-26a

5-4-3 PISTON AND CONNECTING ROD

(1) EH09D

The direction of piston on connecting rod is not specified.

EH12-2D

When installing the piston on the connecting rod, place the valve recess of the piston crown as shown in the illustration to the “MAG” side of the connecting rod.

(2) Apply oil to the small end of connecting rod,

piston and piston pin before assembling. Be sure to use clips on the both side of the

piston pin to secure piston pin in position.

"MA" MARK

Model: EH09D

Fig. 5-26b

"MAG" MARK

VALVE RECESS

Model: EH12-2D

Fig. 5-27

-

31

-

(3) Install piston and connecting rod assembly

into cylinder. Use a piston ring compressor to hold piston

rings. The “MA” mark (EH09D) ,“MAG” mark (EH12-

2D) of the connecting rod is to face the flywheel side of the engine when assembled.

Note:

PISTONRING COMPRESSOR

CONNECTING ROD

("MA"SIDEEH09D)

("MAG"SIDE EH12-2D)

(1) Apply enough oil to lubricate the pis-

ton rings, connecting rod bearings and cylinder bore before assembly.

(2) Set gaps of the piston rings 90 de-

grees apart from each other before assembly.

5-4-4 CONNECTING ROD

(1) Turn crankshaft to bottom dead center, lightly

tap top of the piston until large end of the rod meet crank pin.

(2) Install connecting rod cap to connecting rod.

Make sure to match the alignment marks on the rod caps.

CRANKCASE (FLYWHEEL SIDE)

Fig. 5-28

SECOND RING

OIL RING

TOP RING

Fig. 5-29

Torque connecting rod bolts to specification. M5 x 25 mm connecting rod bolt : 2 pcs. (EH09D) M6 x 34 mm connecting rod bolt : 2 pcs. (EH12-2D)

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D90HED2-21HE

N8.7-9.5 ・m

gk08-06( ・ )mc

tf7.5-3.4( ・ ).bl

N11-8.8 ・m

gk511-09( ・ )mc

tf3.8-5.6( ・ ).bl

(3) Check for free movement of connecting rod

by turning crankshaft slowly.

-

32

-

ALIGNMENT MARK

Model: EH09D Model: EH12-2D

ALIGNMENT MARK

Fig. 5-30

5-4-5 TAPPETS AND CAMSHAFT

G

(1) Oil the tappets and install them.

Push in fully to avoid damage during camshaft installation.

(2) Lubricate bearing surfaces of camshaft.

Align the timing mark on crankshaft gear with the timing mark on camshaft and install camshaft in the crankcase. (See Fig. 5-31a)

CAUTION : Incorrect valve timing will cause mal-

function of the engine.

5-4-6 ADJUST CRANKSHAFT END PLAY

TIMING MARK

CRANKSHAFT

EAR

CAMSHAFT

Fig. 5-31a

(1) Adjust end play to 0.2 mm (0.008") using the

proper spacer. The proper spacer may be determined in the

following manner.

1) Measure the height “A” (From the mating surface to the inner race of the ball bearing.)

2) Measure the depth “B” (From the mating surface to the crank gear.) B-A = SIDE CLEARANCE (mm) (SIDE CLEARANCE)-0.2 mm = THICKNESS OF CRANKSHAFT SHIM (mm)

B-A = SIDE CLEARANCE (in.) (SIDE CLEARANCE)-0.008 in.= THICKNESS OF CRANKSHAFT SHIM (in.) Following are available spacer shims.

TFAHSKNARC

).ni420.0(mm6.0=T

SMIHSRECAPS

Table. 5-1

).ni130.0(mm8.0=T ).ni930.0(mm0.1=T

Fig. 5-31b

-

33

-

(2) Lubricate the oil seal and bearing surfaces.

Coat the surface of the main bearing cover with sealant (Three bond 1216). Place spacer chosen in step (1) on crankshaft. Use an oil seal guide when installing the main bearing cover to avoid damaging the oil seal . Tap the cover into place with a soft hammer. Main bearing cover EH09D M6 x 30 mm bolt and washer : 9 pcs.

EH12-2D M6 x 30 mm bolt and washer : 8 pcs.

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D2-21HE,D90HE

N8.11-8.9 ・m

gk021-001( ・ )mc

tf7.8-2.7( ・ ).bl

EH09D

M6 x 30 BOLT AND WASHER AY : 9 pcs.

EH12-2D

SPACER

SEALANT (

Three bond 1216

MAIN BEARING COVER CP

SPACER

CRANKSHAFT

MAIN BEARING COVER CP

)

CAMSHAFT

CRANKCASE

SEALANT (

Three bond 1216

)

M6 x 30 BOLT AND WASHER AY : 8 pcs.

Fig. 5-32

-

34

-

CRANKSHAFT

CAMSHAFT

CRANKCASE

5-4-7 CYLINDER HEAD

(1) Clean carbon and gum deposits from the valves, seats, ports and guides. Inspect valves, valve seats

and valve guides. (2) Replace valves that are badly burned, pitted or warped. (3) When installing valves in cylinder head, oil the valve stems and insert them into valve guide.

Then place cylinder head on flat table, install valve spring and spring retainer.

(4) Valve guides should be replaced when valve stem clearance exceeds specifications (See “SERVICE

DATA”).

Draw valve guides out and press new guides in.

Refer to “SERVICE DATA” for clearance specifications.

After replacing valves and guides, lap valves in place until a uniform ring shows around the face of

the valve. Clean valves and wash cylinder head thoroughly.

(5) Install cylinder head onto cylinder with new head gasket.

Tighten four flange bolts evenly in three steps by the following tightening torque:

Cylinder head M8 x 55 mm bolt : 4 pcs. (EH09D)

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N0.5 ・m gk05( ・ )mc

tf6.3( ・ ).bl

N8.9 ・m

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tf2.7( ・ ).bl

Cylinder head M8 x 65 mm bolt : 4 pcs. (EH12-2D)

)D2-21HE(euqrotgninethgiT

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N0.5 ・m gk05( ・ )mc

tf6.3( ・ ).bl

N8.9 ・m

gk001( ・ )mc

tf2.7( ・ ).bl

N6.02-6.81 ・m

gk012-091( ・ )mc

tf2.51-7.31( ・ ).bl

N0.62-0.32 ・m

gk072-032( ・ )mc

tf0.03-0.71( ・ ).bl

-

35

-

5-4-8 ROCKER ARMS AND PUSH RODS

(1) Insert push rods into crankcase.

Put push rod tip in the hollow of tappet top.

Note: An oil return slot is located next to the tappet boss. If you do not put the push rod in the

tappet properly, the push rods will fall into the crankcase. Removal of the main bearing cover is necessary to get them out.

(2) Apply oil to rocker arms and assemble them to cylinder head using pivot bolt and nut.

M6 x 60 BOLT AND WASHER AY : 4 pcs.

BOLT (PIVOT) : 2 pcs.

ROCKER ARM

COLLET

ROCKER COVER

SPRING RETAINER

VALVE SPRING

M8 x 55 FLANGE BOLT : 4 pcs.

M6 NUT

: 2 pcs.

EXHAUST VALVE

GASKET

GUIDE PLATE

CYLINDER

HEAD CP

INTAKE VALVE

PUSH ROD

Fig. 5-33

-

36

-

5-4-9 VALVE CLEARANCE ADJUSTMENT

THICKNESS GAUGE

ROCKER ARM

BOLT (

PIVOT

)

NUT

Note: T emporally fit the flywheel in position for

easy operation.

(1) EH09D

Position the piston at the top dead center of

compression stroke by matching the alignment

mark of flywheel with the alignment mark of

crankcase.

EH12-2D

Position the piston at the top dead center of

compression stroke. The top dead center may

be obtained by placing the key slot on the

power take off shaft to 10 o’clock position. (See

Fig. 5-34b) (2) Loosen the nut under the rocker arm and turn

the bolt (pivot) to adjust the clearance between

rocker arm and valve stem end.

Tighten the nut on rocker arm.

Valve clearance : 0.07 - 0.13 mm

(0.0028 - 0.0051 in.)

ALIGNMENT MARKS

Model: EH09D

Fig. 5-34a

45°

Model: EH12-2D

Fig. 5-34b

FLYWHEEL

P.T.O

Note: Check and adjust valve clearance while

engine is cold. Check operation of valves by turning

crankshaft. Then recheck the valve clearance.

(3) Install rocker cover and gasket.

Rocker cover M6 x 25 mm bolt : 4 pcs.

Fig. 5-35

-

37

-

5-4-10 SPARK PLUG

Install spark plug to cylinder head.

Spark plug : NGK BM6A, BMR6A (EH09)

: NGK B6ES, BR6ES (EH12-2D)

)D90HE(euqrotgninethgiT

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N7.41-8.11 ・m

gk051-021( ・ )mc

tf9.01-7.8( ・ ).bl

N5.42-6.22 ・m

gk052-032( ・ )mc

tf1.81-6.61( ・ ).bl

5-4-11 FLYWHEEL MAGNETO

(1) Put the woodruff key in the keyway of crank-

shaft. Wipe off oil and grease thoroughly from the tapered portion of crankshaft and flywheel center hole.

(2) Install the flywheel to crankshaft.

Tighten the flywheel nut with the starter pulley.

euqrotgninethgiT

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N7.41-8.11 ・m

gk051-021( ・ )mc

tf9.01-7.8( ・ ).bl

)D2-21HE(euqrotgninethgiT

N5.62-6.22 ・m

gk072-032( ・ )mc

tf5.91-6.61( ・ ).bl

D90HED2-21HE

N1.94-2.44 ・m

gk005-054( ・ )mc

tf2.63-5.23( ・ ).bl

N0.36-0.95 ・m

gk056-006( ・ )mc

tf0.74-0.34( ・ ).bl

Fig. 5-36

-

38

-

5-4-12 IGNITION COIL

THICKNESS GAUGE

IGNITION COIL

Install ignition coil to crankcase. Pay attention the direction of ignition coil and the

location of code. Adjust air gap between ignition coil and flywheel

using a thickness gauge and tighten bolts. M6 x 25 mm bolt and washer : 2 pcs.

Air gap : 0.3 - 0.5 mm

(0.012 - 0.020 in.)

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gk011-09( ・ )mc

tf0.8-5.6( ・ ).bl

IGNITION COIL

Model: EH09D

Fig. 5-37a

THICKNESS GAUGE

5-4-13 INTAKE PIPE, INSULATOR (EH12-2D)

(1) Install the intake pipe to the cylinder head with

gasket.

M6 flange nut : 2pcs.

M6 x 40 mm bolt and washer : 1pce.

Tightening torque : 9.8 - 13.7 N・m

(100 - 140 kg・cm) (7.2 - 10.1 ft・lb.)

Then put the gasket and insulator on the intake pipe.

M6 NUT : 2 pcs.

GASKET

Model: EH12-2D

Fig. 5-37b

M6 x 40 BOLT AND WASHER AY: 1 pce.

INTAKE PIPE

Fig. 5-38

-

39

-

5-4-14 GOVERNOR, SPEED CONTROL SYSTEM AND CARBURETOR

EH09D

(1) Install governor lever to governor shaft, then tighten the locking bolt temporarily. (2) Install base plate to crankcase. (3) Install speed control lever, friction washer, pivot bolt, etc. to base plate as shown in illustration. (4) Hook governor spring to proper holes of governor lever and speed control lever. (See Fig. 5-40a) (5) Install insulator and gaskets for carburetor to cylinder head.

(6) Install carburetor to cylinder head hooking governor rod to governor lever and throttle lever of carbu-

retor. Hook rod spring over governor rod.

(7) Attach air cleaner base to carburetor. Tighten two flange nuts and a bolt. Connect breather pipe from

rocker cover to cleaner base.

M6 x 8 FLANGE BOLT : 2 pcs.

SPACER

SPEED CONTROL LEVER AY

BASE PLATE CP

GOVERNOR SHAFT

M6 BOLT AND WASHER AY : 1 pce.

RETURN SPRING

ROD SPRING

GOVERNOR LEVER

FRICTION WASHER

INSULATOR

GOVERNOR ROD

GOVERNOR SPRING

M6 PIVOT BOLT

: 1 pce.

GASKET (INSULATOR

CARBURETOR

)

Fig. 5-39a

-

40

-

EH12-2D

(1) Install governor lever to governor shaft, then tighten the locking bolt temporarily. (2) Install speed control lever, pivot bolt, etc. as shown in illustration. (3) Hook governor spring to proper holes of governor lever and speed control lever. (See Fig. 5-40b) (4) Install insulator and gaskets for carburetor to intake pipe.

(5) Install carburetor to intake pipe hooking governor rod to governor lever and throttle lever of carbure-

tor. Hook rod spring over governor rod.

(6) Attach air cleaner base to carburetor. Tighten two flange nuts and a bolt. Connect breather pipe from

rocker cover to cleaner base.

INSULATOR

CARBURETOR

ROD SPRING

WIRE BRACKET

GOVERNOR

LEVER

M6 BOLT AND WASHER AY : 1 pce.

M6 x14 FLANGE BOLT : 1 pce.

Fig. 5-39b

GOVERNOR ROD

GOVERNOR SPRING

NUT

GASKET (

INSULATOR

M6 PIVOT BOLT : 1 pce.

)

SPEED CONTROL LEVER

M6 x 12 FLANGE BOLT : 1 pce.

PROTECTOR

M8 x 16 BOLT AND WASHER AY : 1 pce.

-

41

-

5-4-15 AIR CLEANER

Install the air cleaner gasket and the cleaner base and tighten them with 2-M6 flange nuts.

Then install the element and the cleaner case.

5-4-16 ADJUST GOVERNOR SYSTEM

(1) Turn the speed control lever all the way toward the high speed position and fix it by tightening self lock

nut.

(2) Check that the governor lever is pulled by the governor spring and carburetor throttle valve is fully

open.

(3) Turn the governor shaft clockwise all the way using a screw driver, and tighten lock bolt to secure the

lever on the shaft.

(4) Loosen the self lock nut to allow the speed control lever to move freely.

GOVERNOR ROD SPRING

GOVERNOR ROD

GOVERNOR LEVER

GOVERNOR

GOVERNOR SHAFT

Model: EH09D

Fig. 5-40a

SPRING

Normal hooking

position

SPEED CONTROL

LEVER

GOVERNOR ROD SPRING

GOVERNOR ROD

GOVERNOR LEVER

Normal hooking

position

GOVERNOR

SPRING

SPEED CONTROL

LEVER

GOVERNOR SHAFT

Model: EH12-2D

Fig. 5-40b

-

42

-

5-4-17a CYLINDER BAFFLE, MUFFLER BRACKET and MUFFLER (EH09D)

(1) Temporarily install cylinder baffle, muffler

bracket and blower housing bracket 2 to the

cylinder head.

: M6 flange nut : 2 pcs.

Do not tighten the flange nut fully.

(2) Temporarily install muffler and gasket to cylin-

der head.

: M6 self lock nut : 2 pcs.

: M6 x 12 mm bolt and washer : 2 pcs.

(3) Finally, tighten the self lock nut etc. fully,

according to the following priority.

1 1

1 M6 self lock nut : 2 pcs.

1 1

2 2

2 M6 x 12 mm bolt and washer : 2 pcs.

2 2

3 3

3 M6 flange nut : 2 pcs.

3 3

M6 x 12 BOLT AND

2

WASHER AY : 2 pcs.

MUFFLER

MUFFLER CP

BRACKET CP

3

GASKET (

MUFFLER

euqrotgninethgiT

N8.01-8.8 ・m

gk011-09( ・ )mc

tf0.8-5.6( ・ ).bl

M6 FLANGE NUT : 2 pcs.

BLOWER HOUSING BRACKET CP 2

CYLINDER BAFFLE

)

M6 SELF LOCK

1

NUT : 2 pcs.

Fig. 5-41a

-

43

-

5-4-17b HEAD COVER, MUFFLER BRACKET and MUFFLER (EH12-2D)

(1) Temporarily install head cover and muffler

bracket to cylinder head. : M6 x 18 mm flange bolt : 2 pcs.

(2) Temporarily install muffler, gasket (muf fler) and

spacer (exhaust) to cylinder head. : M8 self lock nut : 2 pcs. : M8 x 16 mm bolt and washer : 4 pcs.

N5.62-5.22 ・m

(3) Finally, tighten the self lock nut etc. fully,

according to the following priority.

1 1

1 M8 self lock nut : 2 pcs.

1 1 2 2

2 M8 x 16 mm bolt and washer : 2 pcs.

2 2 3 3

3 M8 x 16 mm bolt and washer : 2 pcs.

3 3 4 4

4 M8 x 18 mm flange bolt : 2 pcs.

4 4

gk072-032( ・ )mc

tf5.91-5.61( ・ ).bl

N8.01-8.8 ・m

gk011-09( ・ )mc

tf0.8-5.6( ・ ).bl

)8M(euqrotgninethgiT

)6M(euqrotgninethgiT

M8 x 16 BOLT AND

2

WASHER AY : 2 pcs.

MUFFLER

M8 SELF LOCK

1

NUT : 2 pcs.

M8 WASHER : 2 pcs.

M8 x 16 BOLT AND

3

WASHER AY : 2 pcs.

M6 x 18 FLANGE

4

BOLT : 2 pcs.

Fig. 5-41b

GASKET (

MUFFLER

)

A

SPACER (

EXHAUST

A

)

MUFFLER BRACKET

HEAD COVER

-

44

-

5-4-18 BLOWER HOUSING AND RECOIL STARTER

(1) Attach blower housing to crankcase. Tighten

five flange bolts. M6 x 12 mm flange bolt : 5 pcs. Insert the high tension cord from the ignition

coil into the notch of the blower housing so as not to pinch the cord.

(2) Install recoil starter to blower housing.

M6 x 8 mm flange bolt : 4 pcs.

Note: Be careful of pulling direction of starter

rope.

5-4-19 STOP SWITCH

(1) Install stop switch to blower housing. (2) Connect wires referring to the wiring diagram.

-

End of the reassembly

-

CLAMP

STOP SWITCH STOP SWITCH WIRE

Model: EH12-2D

Fig. 5-42

-

45

-

5-5 BREAK-IN OPERATION

A new engine or an engine that has been completely overhauled by being fitted with a new piston, rings, valves and connecting rod should be thoroughly RUN-IN before being put back into service.

Good bearing surfaces and running clearances between the various parts can only be established by operating the engine under reduced speed and loads for a short period of time.

While the engine is being tested, check for oil leaks. Make final carburetor adjustment and regulate the engine operating speed.

petSdaoLdeepSenignEemiT

1petS daoLoNmpr005,2.nim01 2petS daoLoNmpr000,3.nim01 3petS daoLoNmpr006,3.nim01

4petS

5petS

D90HE)PH0.1(Wk7.0

mpr006,3.nim03

D2-21HE)PH4.1(Wk0.1

D90HE)PH9.1(Wk4.1

mpr006,3.nim06

D2-21HE)PH8.2(Wk1.2

Table. 5-2

6. MAGNETO

6-1 OPERATION AND FUNCTION

The ignition system of the EH09D and EH12-2D is a breakerless flywheel magneto with an automatic advancing system.

Being different from the breaker point type ignition system, this system is completely free from such troubles as starting-up failure due to dirty, burnt or corroded point surface.

The electronic automatic advancing ensures extremely easy starts and stable high performance at operating speed by advancing the ignition timing to the most suitable point.

6-2 BASIC THEORY

(1) Revolution of the flywheel generates electricity on the primary side of the ignition coil, and the base

current I Current I

1 flows to the power transistor.

1 turns the power transistor “ON” and the electric current I2 flows.

-

46

-

(2) At lower engine revolution, when the flywheel reached the ignition point the low speed ignition timing

control circuit operates to run the base current I current I

1 to bypass as current I4.

3 to turn the signal transistor A “ON” allowing the

At this moment the power transistor turns “OFF” and the current I

2 is abruptly shut off resulting in the

high voltage generated in the secondary coil which produces sparks at the spark plug.

(3) At higher engine revolution, the advancing control circuit operates at the ignition timing to run the

base current I At this moment the power transistor turns “OFF” and the current I

5 to turn the signal transistor B “ON” allowing the current I1 to bypass as current I6.

2 is abruptly shut off resulting in the

high voltage generated in the secondary coil which produces sparks at the spark plug. The operating timing of the advancing control circuit advances in accordance with the increase of

engine speed resulting in the advancing of ignition timing as shown in Fig. 6-1(b).

I1

Power Transistor

Primary Coil

Secondary Coil

Spark plug

I2

Signal Transistor B

Low Speed

Ignition

Timing

Control Circuit

Resister

I3

Signal Transistor A

Automatic

Advancing

Control

Circuit

I5

I4

I6

Fig. 6-1a

(

B.T.D.C.

IGNITION TIMING

23°

18°

15°

-

)

500 1000 2000 3000

47

-

ELECTRONIC ADVANCING FLYWHEEL

MAGNETO SYSTEM

STEP ADVANCING

ENGINE REVOLUTION

Fig. 6-1b

(

EH12-2D

(

EH09D

(r.p.m.)

)

6-3 WIRING DIAGRAM

● STANDARD

Fig. 6-2

-

48

-

7. AUTOMATIC DECOMPRESSION SYSTEM

EH09D and EH12-2D engines employ an automatic decompression system as a standard feature. This enables easy starting of the engine, with lighter recoil pull. The automatic decompression system releases the compression of the engine by lifting up the exhaust valve at cranking speeds. The following is the explanation of how the system works.

At the end of the compression process, the release lever lifts up the tappet which in turns opens up the exhaust valve slightly to release the compression. The release lever has a flyweight on its end and another end of the lever is a crescent cam. When the engine is cranked, the crescent cam projects above the cam profile and lifts up the tappet because the gravity force on the weight is larger than the centrifugal force on the weight.

TAPPET

FLYWEIGHT

CRESCENT CAM

RELEASE LEVER

EXHAUST CAM

ROTATION

EXHAUST CAM

CAMSHAFT

Fig. 7-1

When the cranking speed reaches a specified r.p.m., the crescent cam is retracted under the cam profile because the centrifugal force applied to the flyweight becomes larger than the force of gravity on the weight and thus it is shifted to the position shown in the illustration below.

FLYWEIGHT

TAPPET

RELEASE LEVER

CRESCENT CAM

EXHAUST CAM

ROTATION

EXHAUST CAM

CAMSHAFT

Fig. 7-2

-

49

-

8a. FLOAT TYPE CARBURETOR (EH09D)

8a-1 OPERATION AND CONSTRUCTION 8a-1-1 FLOAT SYSTEM

The float chamber is located below the carburetor body and, with a float and a needle valve, maintains a constant fuel level during engine operation.

The fuel flows from the fuel tank into the float chamber through the needle valve. When the fuel rises to a specific level, the float rises, and when its buoyancy and fuel pressure are balanced, the needle valve closes to shut off the fuel, thereby keeping the fuel at the predetermined level.

FLOAT

FUEL

NEEDLE VALVE

Fig. 8-1

BY-PASS

PILOT OUTLET

PILOT JET

PILOT AIR JET

MAIN NOZZLE

CHOKE

AIR INTAKE

FLOAT

MAIN AIR JET

MAIN JET

Fig. 8-2

-

50

-

8a-1-2 PILOT SYSTEM

The pilot system feeds the fuel to the engine during idling and low-speed operation. The fuel is fed through the main jet to the pilot jet, where it is metered, and mixed with the air metered by the pilot air jet. The fuel-air mixture is fed to the engine through the pilot outlet and the bypass. At idling speed, the fuel is mainly fed from the pilot outlet.

8a-1-3 MAIN SYSTEM

The main system feeds the fuel to the engine at medium and high-speed operation. The fuel is metered by the main jet and fed to the main nozzle. The air metered by the main air jet is mixed with the fuel through the bleed holes in the main nozzle, and the mixture is atomized out of the main bore. It is mixed again with the air taken through the air cleaner into an optimum fuel-air mixture, which is supplied to the engine.

8a-1-4 CHOKE

The choke is used for easy starting when the engine is cold. When the starter is operated with a closed choke, the negative pressure applied to the main nozzle increases and draws more fuel ; thus richening the mixture and making starting the engine easier.

8a-2 DISASSEMBLY AND REASSEMBLY

Apart from mechanical failures, most of carburetor troubles are caused by an incorrect mixing ratio, which may arise mainly due to a clogged up air or fuel passage in jets, or fuel level variations. In order to assure proper flow of air and fuel, the carburetor must be kept clean at all times. The carburetor disassembly and reassembly procedures are as follows.

8a-2-1 THROTTLE SYSTEM

(1) The spring

the throttle stop screw

(2) Remove the philips screw

ww

w, and pull out the throttle shaft

ww

*Be careful not to damage throttle valve rim.

rr

r can be taken out by removing

rr

tt

t.

tt

qq

q and throttle valve

qq

ee

e.

ee

1

12

15

17

11

3 4 5 62

789

13 16 19 18

14 10

Fig. 8-3

-

51

-

8a-2-2 CHOKE SYSTEM

(1) Remove the philips screws

(2) When reassembling the choke shaft, make sure that the cutout in the choke valve faces the pilot air

jet.

yy

y and choke valve

yy

uu

u, and pull out the choke shaft

uu

ii

i.

ii

8a-2-3 PILOT SYSTEM

(1) Remove the pilot jet (2) Reassembly

Tighten the pilot jet securely. Otherwise, the fuel may leak, causing engine malfunction.

oo

o, using correct tool to avoid damage to it.

oo

8a-2-4 MAIN SYSTEM

(1) Remove the bolt (2) Remove the main jet (3) Reassembly

a) Fasten the main jet securely to the body. Otherwise, the fuel may become too rich and cause

engine malfunction.

!0!0

!0 and take out float chamber body

!0!0

!3!3

!3 and guide holder from the body

!3!3

!1!1

!1.

!1!1

!2!2

!2 .

!2!2

b) The bolt

!1!1

!1.

!1!1

!0!0

!0 tightening torque is 90 kg-cm. Be sure to set the gasket

!0!0

!5!5

!5 and washer

!5!5

8a-2-5 FLOAT SYSTEM

(1) Pull out the float pin

needle valve needs to be replaced, replace it with rubber needle.

CAUTION : When cleaning the jets, use neither a drill nor a wire (because of possible damage of the

orifice which will adversely affect fuel flow). Be sure to use compressed air to blow them clean.

(2) When removing the needle valve and float, gently tap the reverse side of the float pin

more slender than the float pin and remove, since the float pin is pressed into the carburetor body.

!6!6

!6 and remove the float

!6!6

!7!7

!7 and then remove the clip

!7!7

!8!8

!8 and needle valve

!8!8

!4!4

!4 for chamber

!4!4

!9!9

!9. If the

!9!9

!6!6

!6 using a rod

!6!6

-

52

-

8b. FLOAT TYPE CARBURETOR (EH12-2D)

PILOT OUTLET

BY-PASS

PILOT AIR JET

CHOKE

AIR INTAKE

MAIN AIR JET

MAIN NOZZLE

FLOAT

NEEDLE VALVE

FUEL

PILOT JET

FLOAT

MAIN JET

8b-1 OPERATION AND CONSTRUCTION 8b-1-1 FLOAT SYSTEM

The float chamber is located below the carburetor body and, with a float and a needle valve, maintains a constant fuel level during engine operation.

The fuel flows from the fuel tank into the float chamber through the needle valve. When the fuel rises to a specific level, the float rises, and when its buoyancy and fuel pressure are balanced, the needle valve closes to shut off the fuel, thereby keeping the fuel at the predetermined level.

Fig. 8-4

Fig. 8-5

-

53

-

8b-1-2 PILOT SYSTEM

The pilot system feeds the fuel to the engine during idling and low-speed operation. The fuel is fed through the main jet to the pilot jet, where it is metered, and mixed with the air metered by the pilot air jet. The fuel-air mixture is fed to the engine through the pilot outlet and the bypass. At idling speed, the fuel is mainly fed from the pilot outlet.

8b-1-3 MAIN SYSTEM

The main system feeds the fuel to the engine at medium and high-speed operation. The fuel is metered by the main jet and fed to the main nozzle. The air metered by the main air jet is mixed with the fuel through the bleed holes in the main nozzle, and the mixture is atomized out of the main bore. It is mixed again with the air taken through the air cleaner into an optimum fuel-air mixture, which is supplied to the engine.

8b-1-4 CHOKE

The choke is used for easy starting when the engine is cold. When the starter is operated with a closed choke, the negative pressure applied to the main nozzle increases and draws more fuel ; thus richening the mixture and making starting the engine easier.

8b-2 DISASSEMBLY AND REASSEMBLY

Apart from mechanical failures, most of carburetor troubles are caused by an incorrect mixing ratio, which may arise mainly due to a clogged up air or fuel passage in jets, or fuel level variations. In order to assure proper flow of air and fuel, the carburetor must be kept clean at all times. The carburetor disassembly and reassembly procedures are as follows.

8b-2-1 THROTTLE SYSTEM

(1) Remove the philips screw

ww

w, and pull out the throttle shaft

ww

(2) The spring

the throttle stop screw

*Be careful not to damage throttle valve rim.

rr

r can be taken out by removing

rr

qq

q and throttle valve

qq

ee

e.

ee

tt

t.

tt

Fig. 8-6

-

54

-

(2) Setting the attachments off (Fig. 9-2)

-1 : Fix the case and loosen the set-screw.

-2 : Put off the set-screw, the ratchet guide, the friction spring and the ratchet in the same order from above.

(3) Setting the reel off (Fig. 9-2)

-1 : Push the reel lightly so that it will not float up. Move the reel clockwise and counterclockwise about a quarter circle for several times until it moves smoothly.

-2 : Pull up the reel gradually and slowly and put it off from the case.

-3 : In case the spring in the reel is close to pop up, redo the steps of (3)-1 and (3)-2 again.

SET SCREW RATCHET

GUIDE

FRICTION SPRING

RATCHET

REEL

STARTER CASE

WARNING : Do not drop or shake the reel and put it

on a level table because there is a spring set in the disassembled reel.

Disassembly is complete.

WARNING : Before starting the assembly, make sure to wear the protective glasses.

9-1-2 Assembly Steps

(1) Setting the reel into the case.

-1 : Paste grease on the case. (Fig. 9-3)

-2 : Adjust the position of the inner end of the spring, which is set in the reel. (Fig. 9-4)

Fig. 9-2

GREASE PASTING

-3 : Hold the reel so that the shaft/hook part and the inner-end of the spring are hooked together. Drop the reel gently from above into the case.

-4 : Move the reel slightly counterclockwise and make sure the spring is hooked.

-

63

SHAFT / HOOK PARTS

Fig. 9-3

THE POSITION THE END TOUCHES THE RIB OF THE BEARING

Fig. 9-4

-

(2) Setting the attachments

-1: Set the ratchet into the reel. (Fig. 9-5)

THE RATCHET IS KEPT AT CLOSE-POSITION

Fig. 9-5

-2: Holding the ratchet, set the ratchet-guide subassembly. (Fig. 9-6)

(3) Tightening the set-screw.

-1 : Push the ratchet-guide lightly by hand so that the ratchet guide won't move and tighten the set-screw.

SET SCREW

RATCHET GUIDE

FRICTION SPRING

RATCHET GUIDE SUB-ASSEMBLY

Fig. 9-6

ABOUT 200mm

FROM THE REEL

(4) Storing the spring-power.

-1 : Hold the case tight and using both hands, wind up the reel counterclockwise 6 times.

-2 : Set the reel to keep the position, whereby the rope hole of the reel and the rope guide make a direct line. (Fig. 9-7)

Fig. 9-7

WARNING : The spring power is at its most when the reel is being wound. Therefore, do not abruptly

put off your hand nor loosen the pressure of Your finger unintentionally.

-

64

-

(5) Setting the rope. (2 persons required)

-1 : Set the end of the rope through the rope guide and the rope hole of the reel and pull the end about 20 cm out of the reel. (Fig. 9-7)

-2 : Fasten the end of the rope.

-3 : Put the rope into the reel, whereby make sure that the rope will not float up. (Fig. 9-9)

-4 : Hold the rope firmly with one hand at the position about 50 cm from the rope guide and keep the rope slightly pulled so that the rope will not be wound in.

ABOUT 20mm

Fig. 9-8

-5 : Take your hand off the reel gently and release the rope slowly checking the winding power of the spring until the knob reaches the rope guide.

Fig. 9-9

Assembly is complete.

(6) Test the operation of the recoil starter to see if the rope recoils satisfactorily and the ratchets extend

and retract properly. Mount the recoil starter to the engine.

(7) If the spring escapes from the reel when disassembling the recoil, hook the outer end of the spring

onto the notch of the reel and rewind the spring into the housing.

(8) Lubricate the rotating parts, sliding parts and spring with heat resistant grease before reassembling

the recoil and prior to long term storage.

-

65

-

10. TROUBLESHOOTING

The following three conditions must be fulfilled for satisfactory engine start.

1. The cylinder filled with a proper fuel-air mixture.

2. Good compression in the cylinder.

3. Good spark, properly timed, to ignite the mixture. The engine cannot be started unless these three conditions are met. There are also other factors which

make engine start difficult, e. g., a heavy load on the engine when it is about to start at low speed, and a high back pressure due to a long exhaust pipe.

The most common causes of engine troubles are given below :

10-1 STARTING DIFFICULTIES 10-1-1 FUEL SYSTEM

(1) No gasoline in the fuel tank, or the fuel cock closed. (2) The carburetor is not choked sufficiently especially when the engine is cold. (3) Water, dust or gum in the gasoline interfering with the fuel flow to the carburetor. (4) Inferior grade gasoline or poor quality gasoline not vaporized enough to produce the correct fuel-air

mixture.

(5) The carburetor needle valve is held open by dirt or gum. This trouble can be detected as the fuel flows

out of the carburetor when the engine is idling. (Overflow) This trouble may be remedied by lightly tapping the float chamber with the grip of a screwdriver or the

like.

(6) If the carburetor overflows, excessive fuel runs into the cylinder when starting the engine, making the

fuel-air mixture too rich to burn. If this happens, remove the spark plug, and turn the starting pulley a few turns in order to let the rich fuel-air mixture out of the spark plug hole and into the atmosphere. Keep the choke valve open during this operation. Dry the spark plug well, screw it into place, and try to start again.

10-1-2 COMPRESSION SYSTEM

If starting difficulties and loss of power are not due to the fuel system or ignition system, the followings must be checked for possible lack of compression.

(1) Engine inside is completely dried up because of a long period of storage. (2) Loose or broken spark plug. This causes a hissing noise made by air/fuel mixture running out of

cylinder in compression stroke during cranking.

(3) Damaged head gasket or loose cylinder head. A similar hissing noise is produced during compres-

sion stroke.

-

66

-

(4) Incorrect Valve clearance

If the correct compression is not obtained even after remedying the above, disassemble the engine and check further as follows :

a) Valve stuck open due to carbon or gum on the valve stem. b) If the piston rings are stuck on the piston, remove the piston and connecting rod from the engine.

Clean or replace the parts.

10-1-3 IGNITION SYSTEM

Check the followings for lack of sparks. (1) Wires of the ignition coil, spark plug or contact breaker disconnected. (2) Ignition coil damaged and shorted. (3) Spark plug cable wet or soaked with oil. (4) Spark plug dirty or wet. (5) Spark plug electrode gap incorrect. (6) Spark plug electrodes are connected or bridged. (7) Incorrect spark timing. (8) Proper connection of all wires.

10-2 ENGINE MISFIRES

(1) Incorrect spark plug electrode gap. Adjust it to anywhere between 0.7 and 0.8 mm. (2) Ignition cable worn and leaking. (3) Sparks weak. (4) Ignition wire connections loose. (5) Water in gasoline. (6) Insufficient compression.

10-3 ENGINE STOPS

(1) Fuel tank empty. Water, dirt, gum, etc. in gasoline. (2) Vapor lock, i. e., gasoline evaporating in the fuel lines due to overheating of the engine. (3) Vapor lock in the fuel lines or carburetor due to the use of too volatile (winter) gas in the hot season. (4) Air vent hole in the fuel tank cap plugged. (5) Bearing parts seized due to lack of oil. (6) Magneto or ignition coil faulty.

-

67

-

10-4 ENGINE OVERHEATS

(1) Crankcase oil level low. Add oil immediately. (2) Spark timing incorrect. (3) Low grade gasoline is used, or engine is overloaded. (4) Cooling air circulation restricted. (5) Cooling air path misdirected causing loss of cooling efficiency. (6) Cylinder head cooling fins clogged up with dirt. (7) Engine operated in an enclosed space without sufficient cooling air. (8) Exhaust gas discharge restricted, or carbon deposits in the combustion chamber. (9) Engine running on low-octane gasoline detonates due to heavy load at low speed.

10-5 ENGINE KNOCKS

(1) Poor quality gasoline. (2) Engine operating under heavy load at low speed. (3) Carbon or lead deposits in the cylinder head. (4) Spark timing incorrect. (5) Loose connecting rod bearing due to wear. (6) Loose piston pin due to wear. (7) See causes of engine overheat.

10-6 ENGINE BACKFIRES THROUGH CARBURETOR

(1) Water or dirt in gasoline, or low-grade gasoline. (2) Intake valve stuck. (3) Valves overheated, or hot carbon particles in the combustion chamber. (4) Engine cold.

-

68

-

11. INSTALLATION

Engine life, ease of maintenance and inspection, frequency of checks and repairs, and operating cost all depend on the way in which the engine is installed. Review the following instructions carefully for installing the engine.

11-1 INSTALLING

When mounting the engine, carefully examine its position, the method of connecting it to a machine, the foundation, and the method of supporting the engine. When determining its mounting position, in particular, make sure that gasoline and oil can easily be supplied and checked, the spark plug can easily be checked, the air cleaner can easily be serviced, and that the oil can easily be discharged.

11-2 VENTILATION

Fresh air is necessary for cooling the engine and burning the fuel. In the case the engine is operated under a hood or in a small room, temperature rise in the engine room can cause vapor lock, oil deterioration, increased oil consumption, loss of power, piston seizure, shorter engine life, etc., making it impossible to operate the engine properly . It is necessary, therefore, to provide a duct or baffle to guide cooling air to the engine to prevent recirculation of the hot air used for engine cooling, and temperature rise of the machine. Keep the engine room temperature below 50°C even in the hottest period of the year.

11-3 EXHAUST GAS DISCHARGE

Exhaust gas is noxious. When operating the engine indoors, be sure to discharge the exhaust gas outdoors. If a long exhaust pipe is used in such a case, the internal resistance increases causing loss of engine power. Thus pipe inside diameter must be increased in proportion to exhaust pipe length. Exhaust pipe : Less than 3 m long, pipe inside diameter 30 mm ,

Less than 5 m long, pipe inside diameter 33 mm.

11-4 POWER TRANSMISSION TO DRIVEN MACHINES 11-4-1 BELT DRIVE

Take the following notes into consideration. * V-belts are preferable to flat belts. * The driving shaft of the engine must be parallel to the driven shaft of the machine. * The driving pulley of the engine must be in line with the driven pulley of the machine. * Install the engine pulley as close to the engine as possible. * If possible, span the belt horizontally. * Disengage the load when starting the engine. If no clutch is used, use a belt tension pulley or the like.

11-4-2 FLEXIBLE COUPLING

When using a flexible coupling, run out and misalignment between the driven shaft and engine shaft must be minimized. Run out and misalignment tolerance are specified by the coupling manufacturer.

-

69

-

12. SERVICE DATA

“STD” in the following table is the parts dimension from the brand new engine or the spare parts. Whereas, “Limit” shows the maximum allowance for the parts to be used on the engine. If the measurement exceeds beyond the “Limit”, the part needs to be replaced and/or repaired.

12-1 CLEARANCE DATA AND LIMITS

METI

DAEHREDNILYC

ssentalF*

htdiwtcatnoctaesevlaV*

.aidedisniediugevlaV*

Unit : mm (in.)

D90HE

DTStimiL

NAHTSSEL

50.0 )200.0(

.XE.NI

1.1-8.0 )3340.0-5130.0(

815.5-005.5 )2712.0-5612.0(

1.0 )400.0(

0.2 )970.0(

56.5 )4222.0(

Unit : mm (in.)

D2-21HE

METI

DTStimiL

DAEHREDNILYC

ssentalF*

NAHTSSEL

50.0 )200.0(

htdiwtcatnoctaesevlaV*

.XE.NI

0.1-7.0

)930.0-820.0(

.aidedisniediugevlaV*

815.5-005.5 )2712.0-5612.0(

1.0 )400.0(

0.2 )970.0(

56.5 )4222.0(

-

70

-

Unit : mm (in.)

D90HED2-21HE

METI

DTStimiLDTStimiL

REDNILYC

.aidedisnI*

DTS

ts1

gnirober

ts2

gnirober

910.15-0.15 )900.2-800.2(

962.15-052.15

)5810.2-7710.2(

915.15-005.15

)3820.2-6720.2(

derobereboT

ehtnehw

ecnereffid

.xamneewteb

.nimdna

retemaidfo

1.0otdehcaer

.)400.0(

ottiD

--------------------

910.06-000.06 )0363.2-2263.2(

962.06-052.06 )8273.2-0273.2(

915.06-005.06 )6283.2-9183.2(

derobereboT

ehtnehw

ecnereffid

.xamneewteb

.nimdna

retemaidfo

1.0otdehcaer

.)400.0(

ottiD

--------------------

.gniroberretfassenidnuoR*

NAHTSSEL

10.0 )400.0(

--------------------

NAHTSSEL

10.0 )400.0(

--------------------

.gniroberretfayticirdnilyC*

NAHTSSEL

510.0 )6000.0(

--------------------

NAHTSSEL

510.0 )6000.0(

--------------------

NOTSIP

tsurhtnitrikstA(ezisnotsiP*

)noitcerid

DTS

s/ots1

s/odn2

99.05-79.05 )5700.2-7600.2(

42.15-22.15 )3710.2-5610.2(

94.15-74.15 )2720.2-4620.2(

88.05 )1300.2(

31.15 )3210.2(

83.15 )8220.2(

89.95-69.95 )4163.2-6063.2(

32.06-12.06 )3173.2-5073.2(

84.06-64.06 )1183.2-3083.2(

78.95 )1753.2(

21.06 )9663.2(

73.06 )8673.2(

-

71

-

Unit : mm (in.)

D90HED2-21HE

METI

DTStimiLDTStimiL

NOTSIP

ecnaraelcedisevoorggniR*

poT

dn2

gnirliO

080.0-530.0 )1300.0-4100.0(

560.0-010.0 )6200.0-4000.0(

51.0 )600.0(

570.0-030.0 )0300.0-2100.0(

570.0-020.0 )0300.0-8000.0(

51.0 )600.0(

elohnipnotsiP*

900.11-199.01 )4334.0-7234.0(

530.11 )4434.0(

200.31-199.21 )9115.0-5115.0(

530.31 )2315.0(

.aidedistuonipnotsiP*

000.11-299.01 )1334.0-8234.0(

069.01 )5134.0(

000.31-299.21 )8115.0-5115.0(

069.21 )2015.0(

dnanotsipneewtebecnaraelC*

trikstarednilyc

.aera

940.0-010.0 )9100.0-4000.0(

pagdnegnirnotsiP*

poT dn2

gnirliO

poT

53.0-51.0 )410.0-600.0(

dn2

55.0-53.0 )220.0-410.0(

52.0-50.0 )010.0-200.0(

52.0 )010.0(

5.1 )1950.0(

470.0-510.0 )9200.0-6000.0(

4.0-2.0 )610.0-800.0(

52.0 )010.0(

5.1 )1950.0(

-

72

-

Unit : mm (in.)



D90HED2-21HE

METI

DTStimiLDTStimiL

DORGNITCENNOC

.aidedisnidnegiB*

310.02-000.02 )9787.0-4787.0(

dnegibneewtebecnaraelC*

nipknarcdna

1.02 )3197.0(

310.62-000.62 )1420.1-6320.1(

1.62 )6720.1(

360.0-730.0 )5200.0-5100.0(

2.0 )800.0(

640.0-020.0 )8100.0-8000.0(

2.0 )800.0(

.aidedisnidnellamS*

120.11-010.11 )9334.0-5334.0(

80.11 )2634.0(

120.31-010.31 )6215.0-2215.0(

80.31 )0515.0(

llamsneewtebecnaraelC*

nipnotsipdnadne

920.0-010.0 )1100.0-4000.0(

21.0 )7400.0(

920.0-010.0 )1100.0-4000.0(

21.0 )7400.0(

ecnaraelcedisdnegiB*

7.0-1.0 )820.0-400.0(

0.1 )040.0(

7.0-1.0 )820.0-400.0(

0.1 )040.0(

TFAHSKNARC

.aidedistuonipknarC*

369.91-059.91 )9587.0-4587.0(

58.91 )5187.0(

089.52-769.52 )8220.1-3220.1(

58.52 )7710.1(

.aidlanruoJ*

D1 D2

2D,1D

799.91-889.91 )3787.0-9687.0(

-

73

-

2D,1D

799.42-889.42 )1489.0-9389.0(

Unit : mm (in)

D90HED2-21HE

METI

DTStimiLDTStimiL

TFAHSMAC

).XEdna.NI(thgiehmaC*

5.81-3.81 )827.0-027.0(

51.81 )517.0(

8.92-6.92 )371.1-561.1(

54.92 )951.1(

.aidedistuolanruoJ*

epyt"D"

D

1

D

1

D

2

D

2

789.9-279.9 )2393.0-6293.0(

59.9 )7193.0(

489.61-379.61 )7866.0-2866.0(

489.41-379.41 )9985.0-5985.0(

59.61 )3766.0(

59.41 )6885.0(

EVLAV

.aidedistuometsevlaV*

.NI

.XE

554.5-044.5 )8412.0-2412.0(

444.5-624.5 )3412.0-6312.0(

53.5 )6012.0(

554.5-044.5 )8412.0-2412.0(

444.5-624.5 )3412.0-6312.0(

53.5 )6012.0(

metsevlavneewtebecnaraelC*

evlavdna.aid

.ediug

.NI

.XE

870.0-540.0 )1300.0-8100.0(

290.0-650.0 )6300.0-2200.0(

3.0 )210.0(

870.0-540.0 )1300.0-8100.0(

290.0-650.0 )6300.0-2200.0(

3.0 )210.0(

ecnaraelcevlaV*

.XE/.NI

)dloc(

-

74

31.0-70.0 )1500.0-8200.0(

-

Unit : mm (in)

D90HED2-21HE

METI

DTStimiLDTStimiL

TEPPAT

.aidedistuometS*

579.7-069.7 )0413.0-4313.0(

.aidedisniediuG*

510.8-000.8 )6513.0-0513.0(

ecnaraelcediugteppaT*

550.0-520.0 )2200.0-0100.0(

HTGNELEERFGNIRPSEVLAV

7.62 )50.1(

--------------------

5.03 )2.1(

--------------------

).XEdna.NI(ELGNATAESEVLAV

)a(elgnarettucevlaV*

)b(htdiwtcatnocevlaV*

bb

a

09:a °

-

1.1-8.0:b

75

0.2

)340.0-130.0(

)970.0(

-

09:a °

0.1-7.0:b )930.0-820.0(

0.2 )970.0(

12-2 TORQUE SPECIFICATIONS

SMETI

euqrotgninethgiT

N・・・・・mgK ・・・・・ mctf ・・・・・ .bl

daehrednilyC

stlob

dorgnitcennoC

stlobpac

)D90HE(6.02-6.81012-0912.51-7.31

)D2-21HE(0.62-0.32072-0320.03-0.71

)D90HE(8.7-9.508-067.5-3.4

)D2-21HE(0.11-8.8511-093.8-5.6

)D90HE(1.94-2.44005-0542.63-5.23

tunleehwylF

)D2-21HE(0.36-0.95056-0060.74-0.34

gniraebniaM

stlobrevoc

gulpkrapS

)D90HE(

gulpkrapS

)D2-21HE(

)D90HE(8.11-8.9021-0017.8-2.7

)D2-21HE(8.11-8.9021-0017.8-2.7

enoweN7.41-8.11051-0219.01-7.8

gninethgiteR5.42-6.22052-0321.81-6.61

enoweN7.41-8.11051-0219.01-7.8

gninethgiteR5.62-6.22072-0325.91-6.61

)D2-21HE(epipekatnI7.31-8.9041-0011.01-2.7

)D90HE(8.01-8.8011-090.8-5.6

tunrelffuM

)D2-21HE(5.62-5.22072-0325.91-5.61

12-3 OIL GRADE CHART

Comparison between oil viscosity and temparature

5W

10W

32

20W

#20

#30

10W-30

10W-40

0

10 50

20 68

30 86

Single grade

Specified

Lubricant

Quality

Multigrade

-

20

-

4

-

10

14

Use oil classified as SE or higher. Multi-grade oil tends to increase its consumption at high ambient temperature.

#40

40 °C

104 °F

-

76

-

13. MAINTENANCE AND STORAGE

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.

13-1 DAILY MAINTENANCE

SMETIECNANETNIAMSKRAMER

.enignemorfffahcdnatsudyawanaelC)1 .tsudotevitisnesyllaicepsesiegaknilronrevoG

,ynafI.metsysleufmorfegakaelleufkcehC)2

.strapyrassecenecalperrosrenetsafnethgiter

finethgiterdnaerawdrahesoolroftcepsnI)3

.yrassecen

.kramllufotddadnalevelliokcehC)4

.straprehtofoegakaerb

nitluserdnaffoemocyamstundnastlobesooL

13-2 INITIAL 20 HRS. MAINTENANCE

SMETIECNANETNIAMSKRAMER

.lioesacknarcecalpeR)1 .noitareponi-nurmorfegdulsevomeroT

13-3 EVERY 50 HRS. (10 DAYS) MAINTENANCE

SMETIECNANETNIAMSKRAMER

.lioesacknarcegnahC)1 .raewsnekciuqliodetanimatnoC

.renaelcrianaelC)2

.gulpkrapsnaelcdnakcehC)3 .repapyremehtiwhsiloproenilosagnihsaw,ytridfI

-

77

-

13-4 EVERY 100-200 HRS. (MONTHLY) MAINTENANCE

SMETIECNANETNIAMSKRAMER

.knatleufdnaretlifleufnaelC)1

.ffahcdnatridevomerdnametsysgnilooctcepsnI)2

13-5 EVERY 300 HRS. or YEARLY MAINTENANCE

SMETIECNANETNIAMSKRAMER

ecnaraelcevlavtsujdadnakcehC)1

13-6 EVERY 500

-

600 HRS. MAINTENANCE

SMETIECNANETNIAMSKRAMER

.daehrednilycmorfnobracevomeR)1

.roterubracnaelcdnaelbmessasiD)2

snifneewtebpunaelcdnagnisuohrewolbevomeR

.gnisuohdna

kcalsesuacrebmahcnoitsubmocnistisopednobraC

.rewopfo

13-7 EVERY 1000 HRS. (YEARLY) MAINTENANCE

SMETIECNANETNIAMSKRAMER

.enigneluahrevO)1

.raeyaecnosenilleufecalpeR)2 .egakaelleufybdesuacsdrazahdiovA

.straptcerrocdnanaelC

.strapyrassecenrehtodnasgnirnotsipecalpeR

13-8 ENGINE STORAGE

(1) Perform the above 13-1 and 13-2 maintenance jobs. (2) Drain fuel from the fuel tank and carburetor float chamber. (3) To prevent rust in the cylinder bore, apply oil through the spark plug hole and turn the crankshaft

several turns by hand. Reinstall the plug. (4) Turn the starting pulley by hand and leave it where the resistance is the heaviest. (5) Clean outside of the engine with oiled cloth. (6) Put a plastic cover or the like over the engine and store the engine in dry place.

-

78

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PRINTED IN THE USA

Robin EH09 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual