Robin EY08D User manual

ROBIN AMERICA, INC.
ROBIN TO WISCONSIN ROBIN
ENGINE MODEL CROSS REFERENCE LIST
ROBIN
EY08
EY15
EY15V
EY20
EY2OV
EY23
EY28
EY3
5
EY40 -
EY45V
EY2
1
EY44
EY18-3
EY25
EY27
EH11
EH12
EH15
EH17
EH21
EH25
EH30
EH30V
EH34
EH34V
EH43V
EC13V
DY23
DY27
DY30
DY3
5
DY41
WISCONSIN ROBIN
SIDE VALVE
W 1-080
W1-145
W1-145V
W1-185
W1-185V
W1-230
W 1-280
W 1-340
W 1-390
Wl-45OV
EY21W
EY44W
EY18-3W
EY25W
EY27W
OVERHEAD VALVE
WO1-115
wo1-120
WO1-150
WO1-170
wo1-210
WOl-250
WO 1-300
WO1-300V
WO1-340
WO
1 -340V
WO 1-43OV
TWO CYCLE
WT1-125V
DIESEL
WRD 1-230
WRD 1-270
-1-300
WRD1-350
WRD1-410
0
0
0

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 Maximum Output ........ 2
3 . FEATURES .................................................. 3
4 . GENERALDESCRIPTION of ENGINECONSTRUCTION ................... 4
4-1
4-2
4-3
4-4
4-5
4-6
4-7
4-8
4-9
4-10
4-11
4-12
4-13
4-14
Cylinder. Crankcase ........................................ 4
Main BearingCover ......................................... 4
Crankshaft .............................................. 4
Connecting Rod andPiston ................................... 5
Camshaft ............................................... 5
Valve Arrangement ......................................... 5
Cylinder Head ............................................ 6
Governor ............................................... 6
Cooling ................................................. 6
Lubrication .............................................. 6
Ignition
................................................ 7
Carburetor .............................................. 7
Air Cleaner .............................................. 7
Sectional View of Engine ..................................... 8
5 . DISASSEMBLY and REASSEMBLY .................................. 10
5- 1 PreparationandSuggestion .................................... 10
5-2 SpecialTools ............................................. 10
5-3 How To Disassemble ........................................ 12
5-4 How To Reassemble ........................................ 16
6 . MAGNETO ................................................... 24
6-1
Magneto ................................................ 24
6-2
Magneto Trouble Shooting .................................... 24
7 . GOVERNORADJUSTMENT ....................................... 25
8 . CARBURETOR ................................................ 26
8-1 Operation and Construction ................................... 26
8-2 DisassemblyandReassembly
.................................. 27

Section Title Page
9 . BREAK-INOPERATION Of REASSEMBLEDENGINE ..................... 28
10 . ROBINSOLIDSTATEIGNITIONENGINE(U.T.C.I.) ..................... 29
10-1 Features ................................................ 29
10-2
Basic Principle of U.T.C. I ..................................... 29
I1 . ROBINOIL SENSOR SYSTEM(FLOAT SYSTEM) ....................... 30
11-1 Features ................................................ 30
11 -2 Basic Principle ............................................ 30
11 -3 CheckingProcedures ........................................ 32
11 -4 Precautions .............................................. 33
11-5
Wiring ................................................. 33
12 . TROUBLESHOOTING ........................................... 34
12-
1 Starting Difficulties ......................................... 34
12-2
EngineMisfires ............................................ 35
12-4
EngineOverheat ........................................... 35
12-3
Enginestops ............................................. 35
12-5 Engine Knocks ............................................ 36
12-6
Engine Backfiresthrough Carburetor ............................. 36
13 . INSTALLATION ............................................... 37
13-1
Installing ................................................ 37
13-2
Ventilation .............................................. 37
13-3
Exhaust Gas Discharge ....................................... 37
13-4
Power Transmissionto Driven Machines ........................... 37
13-5 Wiring ................................................. 38
14 . CHECKS and CORRECTIONS ...................................... 39
15 . TABLE of CORRECTIONSTANDARDS ............................... 40
16 . MAINTENANCE and STORING ..................................... 45
16-1
Daily Checksand Maintenance ................................. 45
16-2
Every 20 Hours Checksand Maintenance .......................... 45
16-3
Every 50 Hours (IO days) Checksand Maintenance .................... 45
16-4 Every 100 . 200 Hours (Monthly)Checksand Maintenance .............. 45
16-5
Every 500 . 600 Hours (Semiannual)Checksand Maintenance ............ 46
16-6 Every 1000 Hours (Yearly) Checks andMaintenance ................... 46
16-7 Preparationfor LongAbeyance ................................. 46

1. SPEC1 FICATIOMS
Model EY08BNEY08D
Air-Cooled, 4-Cycle, Vertical, Single Cylinder Gasoline Engine
Bore x Stroke (in)
77.6 cc (4.74 cu. in)Piston Displacement(cu. in)
51 mm 'x 38 mm (2.01" x 1.50")
Compression Ratio 6.5
Continuous RatedOutput (HP/rpm) 1.0/3000
1.4/3600
1 .O? 1500
1.4/1800
Max. Output (HP/rpm)
0.72/16000.36/3200
Max. Torque (kg-m/rpm)
2.0/2
1 00
2.0/4200
Direction of Rotation 1 Counterclockwise Facingto P.T.O. Shaft Clockwise Facing to P.T.O. Shaft
Cooling System
I ForcedAir Cooling
~
Lubrication SplashingType
Lubricant Automobile OilClass
SC
~~
Carburetor Horizontal Draft, Float Type
~~
Fuel
320
at continuous rated output operationFuel Consumption Ratio (gr/Hp-h)
Non-leadedAutomobile Gasoline
Fuel Feed
I
Gravity Type
Fuel
Tank Capacity
I
Approx. 1.5 liter (0.40 U.S. gal.)
Reduction Ratio
I
-
1 /2
Speed Governor
8.5 kg (18.7 Ibs.)
8 kg (17.6 Ibs.)
DryWeight (Ibs.)
Recoil Starter
Starting System
-
LightingCapacity (V-W)
NGK-BM4A (S.T.D.)
Spark Plug
Flywheel MagnetoType (Solid
State Ignition) IgnitionSystem
Centrifugal Flyweight Type
Length (in)
326 mm (12.83")
Height
(in)
264 mm (10.39")
Width (in)
Dimensions
252 mrn (9.92")
-1 -

2. PERFORMANCE
2-1 MAXIMUM OUTPUT
The maximum output ofan engine is such standard poweras developed by the engine, after itsinitial break-in
period with all themoving parts properlyworn in,when operating with a fully open throttlevalve, Therefore,
a new engine may not develop the maximum output in the beginning because the moving parts are not in a
properly worn-in condition.
2-2 CONTINUOUSRATEDOUTPUT
The continuous rated output of an engine is such power as developed by that engine when running continu-
ously at an optimum speed, and mostfavorable from theviewpoint of engine life and fuel consumption ratio,
with the governor in operation. Itis suggested, therefore, that when designing a driving system
for any mech-
anism, with this engine
as prime mover, the continuous power requirement of that mechanism be kept below
the continuousrated output specified.
2-3 MAXIMUM TORQUE and FUELCONSUMPTION RATIO at MAXIMUM OUTPUT
These mean the maximum torque of the output shaft and fuel consumption ratio at the maxiumum output
of
an engine.
HP
L
W
0
a
3’
L
0
I
PERFORMANCE CURVE
MODEL EY08D
( ) for BN type
0.45
0.40
0.35
0.30
2.5
2.0
1.5
1 .o
0.5
2000 3000 4000
(1 000) (1 500) (2000)
Revolution
- r.p.m.
(0.9) kg-rn
-2-

3. FEATURES
1. Compact, lightweight, durable, powerful4cycle air cooled engine embodying ingeniousdesign techniques
and skilful workmanship.
2. Simpleconstruction,smartappearance,maximum easiness of start owing toautomatic decompression
device
3. Pointless Solid State ignition systemis newldy adopted for preventing poorigniting.
4. Reliable prime mover for varietyof purposes with smooth speed controlrby a governor under varying load
conditions.
5. Economical because fuel consumption is very low
-3-

4. GENERALDESCRIPTION of ENGINECONSTRUCTION
4-1 CYLINDER,CRANKCASE
Thecylinderand crankcaseare single piece alumi-
num die casting. The cylinder liner, made ofspecial
cast iron, is built into the alminumcasting. The
in-
takeandexhaustports arelocated onone side of
the cylinder, and are also insertedinto thecasting.
The crankcase is separable on the output shaft side,
where the main bearing cover
is attached to it.
(See Fig.
1 .)
Fig. 1
4-2 MAIN BEARING COVER
The main bearing cover made of aluminum die castingis built onto the output shaftside of the crankcase so
that theinside of theengine can readily be checkedbysimply removing the cover. Itis provided with a flange
and boss for directly mounting machines,
such as generators and pumps.
Two oil gauges also serving
as oil filler caps can be mounted. (See Fig. 2 and Fig. 3.)
Oi I
Ring for Centering
!ID Oil Gauge
Fig. 2
4-3 CRANKSHAFT
The crankshaft is forged ofcarbon steel,and the
crankpin
is induction-hardened.Ithas acrank gear
pressure-fitted on the output end.(See
Fig. 4.)
Fig. 3
~~
Induction Hardening
(Portion ofCrankpin)
\
CrankGear (Pressure-fit)
Fig. 4
-4-

The connecting rodis made of aluminum die casting,
whichitself serves as bearings at both the large and
small ends. The large end cap and the oil scraper are
moulded in a unit forsplashing the lubricatingoil.
The pistonis cast
of aluminum alloy, and hasgrooves
for receiving two compression rings and one
oil ring.
(See Fig.
5.)
4-4 CONNECTINGROD and PISTON
4-5 CAMSHAFT
In the EY08Dengine, the camshaftis integrally built
with a cam gear of special cast iron, and has intake
and exhaust cams. Also the camshaft has aluminum
plainbearings attached to both ends.
(No ball bear-
ing is used.) (See Fig.
6.)
In the EY08BN engine,the camshaft is forged of car-
bon steeland is providedwithaforce-fit cam gear.
@ It serves also as the driving shaft, beingdriven at half
the crankshaftspeed,anda ball bearing is used at
the P.T.O. shaft side.
4-6 VALVEARRANGEMENT
The intake valveis locatedupstream of the cooling
air with the result that the carburetor is intensively
cooled.(See Fig.
7.)
Top Ring
Second Ring
Oil Ring
Connecting
Rod
Oil Scraper
\I
L
Fig. 5
:
Fig. 6
Direction of
Cooling Wind
Fig. 7
-5-

4-7 CYLINDERHEAD
The cylinderhead is analuminumdie casting, and
forms aRicardotypecombustionchamber with
ample area for high combustion efficiency.
(See
Fig. 8.)
4-8 GOVERNOR
Thegovernor is acentrifugalflyweight type which
permitsconstantoperation-atthe selected speed
against load variations.Govrnor gear is installed on
the bearing cover without fail, and
it engages with
the cam gear after reassembling. (See Fig.
9.)
I
Fig. 8
Main Be
!mor Sleeve
Spacer
Q
-
Governor Gear Complete
Fig. 9
4-9 COOLING
The cooling fan serving also as a flywheel coolsthe cylinderand the cylinder head by forced air cooling. Cyl-
inder baffles
and head cover areprovided forguiding the cooling air.
4-10 LUBRICATION
Therotatingand sliding partsare being lubricated
by scooping
and splashing the oil in the crankcase
with the
oil scraper. (See Fig. 10.)
Fig. 10
-6-

4-11 IGNITION
The ignition system is a flywheel magnetotype with
ignition timing set at
25" before TDC. The magneto
is composed
of a flywheel and ignition coil. The fly-
wheel serving also as a fanis mounted directly on the
crankshaft,andtheignition coil in the crankcase.
(Forfurtherdetails,refertoSection
on the Mag-
neto.) (See
Fig. 11 .)
4-12 CARBURETOR
A horizontaldraftcarburetor is employed.Ithas
been carefully setafter thorough tests toassure satis-
factory start up, acceleration, fuel consumption, out-
put performance, etc.
For construction and order details, refer to theSec-
tiononCarburetorConstruction, Disassembly and
@ Reassembly.(SeeFig. 12.)
4-13AIRCLEANER
The air cleaner of the standard ty
:ngine is an 0 b-
longtype using a spongeelement. (A cyclonetype
semi-wet doubleelement air cleaner is optionally
available.) (See
Fig. 13.)
I IgnitionCoil
Fig. 1 1
Fig. 12
Air Cieaner for
Standard Type Cyclone Type
(Option)
Fig. 13
-7-

4-14 SECTIONAL VIEW of ENGINE
MODEL EY08D
-8-

Stop Button
Connecting Rod
Crankcase
MODEL EY08D
Air Cleaner
Carburetor
Intakeand
Exhaust Valve
Tappet
Camshaft
Governor Shaft
-9-

5. DISASSEMBLY and REASSEMBLY
5-1 PREPARATIONS and SUGGESTIONS
1) When disassembling the engine, remember well the locations of individual parts so that they can be reas-
sembed correctly.
If you are uncertain of identifying some parts, it is suggested that tags be attached to
them.
2) Have boxes ready to keep disassembed parts by group.
3) To prevent missing and misplacing, temporarily assemble each group ofdisassembed parts.
4) Carefully handle disassembed parts, and clean them with washing oil.
5) Use the correct tools in the correct way.
5-2 SPECIAL TOOLS
For yourreference, thefollowing showsspecial tools of Robin Engine forDisassembly, Measuring and Inspec-
tion Instruments.
Part No.
2099500407
2309500107
2079500307
2309500207
2059500107
Tool
Flywheel Puller
(with
bolt)
Valve Spring
Retainer
Valve Guide
Puller
Use
For pulling off
Flywheel
For mountingand
dismounting Valve
SpringRetainer
andRetainer
Lock
For pullingoff
Valve guide
Applicalbe
Model
EY08
EY10, 13, 14
EY
15,18, 20
EY23, 25, 27,
EY33
EY35,40,44
EC05.07, 10
EC17,25.37
EY08
EY10,13, 14
EY15, 18,20
EY23
EY25.27, 33
EY35,40,44
EY08
EY10
EY13,
14
Shape
-10-

Part No.
2069500107
2279500107
207 95001 07
“20248
Tool
Valve Guide
Puller
Timing Tester
Use
For pulling off
Valve guide
For adjusting
timing
Applicalbe
Model
EY18.23
EY 15,ZO
EY25, 27
EY10,
13, 14
EY 15,18,20
EY25,27,33
EY35,40,44
EC03,04,05
EC07,10,
17
EC25,37
Shape
- 11 -

5-3 HOW TO DISASSEMBLE
*Length of the boltindicates the length fromthe bolthead bottom surface to thethreaded end.
Order
5
I tern
Fuel tank
Recoil starter
Tank bracket
Head cover
Fan cover
Muffler cover
Muffler
Air cleaner
Procedures
(1) Close the fuel cock.
(2) Disconnect the fuel pipe between the fuel
strainer and carburetor at the carburetor
side.
(3) Remove the fuel tank from the tank bracket.
M6
x 14 mm bolt : 3 pcs.
(1) Remove the recoil starter.
M6
x 8 mmbolt : 3 pcs.
(1) Remove the tank bracket, thehead cover,
and the fancover from the crankcase and
the cylinder head.
M6
x 10 rnm bolt : 2 pcs.
M6
x 12 bolt : 1 pce.
M6 nut
: 2 pcs.
(1) Remove the muffler cover 1 from the
muffler.
M6
x 8 mm bolt : 2 pcs.
(2) Remove the muffler from the cylinder
portion
of the crankcase.
M6
x 28 mrn bolt
: 1 pce.
M6
x 50 mm bolt
: 1 pce.
(1) Remove the air cleaner cover and the
(2) Remove the air cleaner case from the
element.
carburetor.
M6 nut
: 2 pcs.
(3) Disconnect the breather pipe.
Remarks
Sems bolt
Fastened together
Remove the primary
wire of the stop but-
ton.
Air cleaner is fasten-
ed together with the
carburetor.
Governor Lever
Governor Spring
Lock Bolt
{--) ,Governor RodSpring
Governor
Rod
Lever
L
' High Speed Set Screw
Governor Shaft
Fig. 14
Tool
10 mm box spanner
IO mm boxspanner
10 m box spanner
Ir
10 mm spanner
10 mm box spanner
x 10 mm spanner
10 mm box spanner
- 12 -

Order Itern Procedures
I Remarks I Too I
6 Governor lever
and the relative
parts
Carburetor
Starting pulley
Flywheel
(1) Remove the governor Iever from the gover-
M6 x 25 mmbolt : 1 pce.
nor shaft.
(2) Remove the governorrod and rod spring
(3) Remove the carburetor from the
from the carburetor.
cylinder portion
of the crankcase.
Just loosen the bolt,
unnecessary to take
out the bolt.
10 mm box spanner
or
10 mm spanner
(1) Remove the startingpulley from the
fly-
Be careful not to
wheel. damage the blades
of
M12 nut : 1 pce. the flywheel with
a
Fit a box or socket wrenchover the fly-
wheel nut, and strike it hard witha ham- driver and a like.
wise with a hammer.
mer to remove the nut and spring washer. Strlke counterclock-
(See Fig.
15)
17 mm box spanner
or socket wrench
(1) Remove the flywheel from the crankshaft. Fit the flywheel
puller as shown
in
Fig. 16, turn the
center bolt clock-
wise and pull out
the flywheel.
Fig. 15
Fig. 16
Order
I tern
Procedures
~ ~~~~~~~~~~~ ~ ~~
9
(1) Remove the plug terminal from the spark
Ignition coil plug and remove the ignition coil from the
crankcase.
M6 x 25 mm bolt : 2 pcs.
10
(1) Remove the sparkplug from the cylinder
Spark plug he ad
Remarks
Sems bolt
7
10 mm box spanner
I
19mm box spanner
- 13 -

Order I Item
11 Cylinder head
I
l2 I
Intake and
exhaust valve
13
I Main bearing
cover
Procedures
(1) Remove the M6 bolts and remove the cylin-
M6 x 32 mm bolt : 5 pcs.
M6 x 40 mm bolt : 2 pcs.
(2) Remove the cylinder head gasket from the
der head from thecrankcase
crankcase.
(1) Remove the inner and outer tappet covers
M6 x 12 mm bolt : 2 pcs.
from the crankcase.
(2) Pull out theintake and exhaust valve.
(3) Remove the valve spring and the valve
spring retainer.
(1) From the crankcase remove the bolt fasten-
M6 x 25 mm bolt : 6 pcs.
(2) Remove the cover, lightly tapping the cover
ing the main bearing cover.
evenly with aplastic hammer.
\
(-) Driver
\
Fig. 17
Remarks
M6 x 40 mm bolt is
special bolt.
Put the notch on the
outer circumference
of thespring retainer
on this side.
Hook the medium
size
(-) driver at the
dent (lower side)
of
the spring retainer
and pull out the
valves,while pulling
the spring retainer
toward you.
(See Fig.
17.)
Sems bolt
Be careful not to
damage the oil seal.
(See Fig.
18.)
Tool
10 mm box spanner
The front is this
sidf
(-) driver
10mm
box spanner
Main/Bearing Cover
I PlasticHammer
Fig. 18
- 14 -

Procedures I Remarks I Too I
(1) Remove the camshaft from the crankcase. To prevent the tap-
pets from falling or
damaging, place the
crankcase
on the
side. (See Fig.
19 .)
15
Tappet
~~~ ~~~~ ~~~ ~~
I (1) Remove the tappets from the crankcase. Before removing put
a markof intake or
exhaust
on each
tappet.
Order
16
17
18
I tern
Connecting rod
and piston
Piston and
piston pin
Crankshaft
Camshaft
Procedures
(1) Scrape off carbon and other foreign deposits
from theupper parts of the cylinder and
piston, and then straighten out the bent
tabs of the lock washers
on the connect-
ing rod, and remove two pieces of the bolt.
(2) Remove the lock washer and the connecting
rod cap from thecrankshaft.
(3) Turn the crankshaft until the piston is raised
up to the hghestposition, push the connect-
ing rod
up, and remove the piston out of the
top
of the cylinder.
(1) Remove the twoclips, pull out thepiston
pin, and take thepiston off from the small
end of the connecting rod.
(2) Spread the open ends of the piston rings
and remove them from the piston.
(1) Remove the woodruff key (for the mag-
neto).
(2) Lightly hammer the magneto end of the
crankshaft, and pull it out of the crank-
case.
- 15 -
Remarks I Tool
8 mm box spanner
or
8 mm spanner
Pay attention to the
direction
of the con-
necting rod cap.
Be careful
not to
damage the inside of
the small end of the
connecting rod.
Be careful not to
break the rings by
spreading too much.
Be careful not to
damage the oil seal.

5-4 HOW TO REASSEMBLE
.Precaution in reassembling
Every and each part should becleaned thoroughly. Especially, pay utmost care and attentionto theclean-
liness of the piston, cylinder, crankshaft, connecting rod andbearings.
Scrape completely off carbons from the cylinder head and the upper part of the piston; especially the
carbon adhered in the groove of the pistonring should be carefully and completely taken out.
Carefully check the lip portion of every
oil seal. If faulty one is found, replace it without any hesitation.
Apply enough oil
to the lip portion of theoil seal when reassembling.
Replace all the gaskets with new ones.
Replace the key, pin, bolt, nuts, etc. with new one,if necessary.
Whenever tightening torque
is specified, conform to thespecified figures.
Apply oilto therevolutionary parts and friction surfaces, when reassembling.
Check and adjustthe clearances of various portions and thenreassemble.
When some main portions areassembled in the course of reassembling, turn
or move the gadgets by hand
and pay attention to the frictionalnoise and resistance.
*Sequence and precautionsin reassembling
5-4-1 GOVERNOR SHAFT
1) Insert thegovernor shaft into thecrankcase.
2) Place the clips on the governor shaft.
5-4-2 CRANKSHAFT
1) Inser the crankshaft into the crankcase as shown
. Note: Be careful not to damage the oil seal lip.
in Fig. 20.
2) Put woodruff key (for magneto) in place.
Shaft
Fig. 20
-16-