Robin America EH63 User manual

SERVICE
MANUAL
EH63, 64, 65 and EH72
ENGINES
Models
PUB-ES2158
Rev. 08/09

© Copyright 2009 Robin America, Inc.
Robin America, Inc.
905 Telser Road • Lake Zurich, IL 60047 • Phone: [phone] • Fax: [phone]
e-mail: [email protected] • www.subarupower.com

CONTENTS
Section Title Page
1. SPECIFICATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2. PERFORMANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
3. FEATURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. GENERAL DESCRIPTION OF ENGINE COMPONENTS . . . . . . . . . . . . . . . . . . . 8
5. DISASSEMBLY AND REASSEMBLY
5-1 PREPARATIONS AND SUGGESTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5-2 SPECIAL TOOLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
5-3 DISASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5-4 REASSEMBLY PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
5-5 BREAK-IN OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
6. LUBRICATION SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
7. FUEL SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
8. ELECTRIC SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
9. TROUBLESHOOTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
10. INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
11. SERVICE DATA
11-1 STANDARD DIMENSIONS AND SERVICE LIMITS . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
11-2 TIGHTENING TORQUE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
12. MAINTENANCE AND STORAGE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

– 1 –
1. SPECIFICATIONS
EH63DMODEL
Type Air-Cooled, 4-Stroke, V-Twin Cylinder, Horizontal P.T.O. shaft, OHV Gasoline Engine
Bore x stroke mm (in.)
mm (in.)
L (U.S. gal.)
V - A
kg (lb.)
Counterclockwise as viewed from P.T.O. shaft side
Displacement cm3(cu. in.)
Compression Ratio
Continuous Output kW (HP) / r.p.m.
2 - 80 x 65 (3.15 x 2.56) 2 - 84 x 65 (3.31 x 2.56)
653 (39.9) 720 (43.9)
8.3
EH64D EH65D EH72D
10.8 (14.5) / 3600 11.9 (16.0) / 3600 12.7 (17.0) / 3600 13.4 (18.0) / 3600
Maximum Output
Direction of Rotation
Forced Air Cooling Cooling System
Overhead Valve (OHV) Valve Arrangements
Full pressure type (Trochoid Pump) Full pressure type
with oil Cooler
Lubrication
Automotive Engine Oil SAE #20, #30 or 10W-30; Class SE or higher Lubricant
1.55 (0.41) Capacity of Lubricant
Down Draft, Float Type Down Draft, Float Type
(With Accel Pump)
Carburetor
Automotive Unleaded Gasoline Fuel
Diaphragm Pump (Pulse type) Fuel Feed System
Flywheel Magneto (Solid State) Ignition System
NGK-BP6ES Spark Plug
Charging Capacity
Electric Starter Starting System
Centrifugal Flyweight Type Governor System
Double Element Type Air Cleaner
46 (101.3)44 (97.0)
12 - 15 (STD)
12 - 30 (Option)
Dry Weight
317 x 477 x 475 (12.5 x 18.8 x 18.7) Overall Length×Width×Height
*Specifications are subject to change without notice.
kW (HP) / r.p.m.
13.4 (18.0) / 3600 15.3 (20.5) / 3600 16.4 (22.0) / 3600 18.6 (25.0) / 3600
Maximum Torque N•m / r.p.m.
(kgf•m / r.p.m.)
(ft•lb. / r.p.m.)
43.3 / 2000
(4.41 / 2000)
(31.90 / 2000)
44.3 / 2200
(4.52 / 2200)
(32.69 / 2200)
45.6 / 2500
(4.65 / 2500)
(33.63 / 2500)
53.6 / 2500
(5.5 / 2500)
(39.78 / 2500)

– 2 –
2. PERFORMANCE
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 worn in after the initial break-in period.
A new engine may not produce full maximum output while its moving parts are still not broken-in.
NOTE :
Power curves shown in the following charts are made in conformity to SAE internal combustion engine
standard test code J1349
2-2 CONTINUOUS RATED OUTPUT
The continuous rated output is the output of an engine at optimum governed speed which is most favorable
from the view point of engine's life and fuel consumption.
When the engine is installed on a certain equipment, it is recommended that the continuous output required
from the engine be kept below this continuous rated output.
2-3 MAXIMUM TORQUE
The maximum torque is the torque at the output shaft when the engine is producing maximum output at
certain revolution.

– 3 –
2-4 PERFORMANCE CURVES
EH63D
2000 2400 2800 3200 3600
5
(6.7)
10
(13.4)
15
(20.1)
REVOLUTION r.p.m
HORSEPOWER
kW
(HP)
TORQUE
N-m
(kgf-m)
45 (4.59)
35 (3.57)
CONTINUOUS
RATED HP
RECOMMENDED
HORSEPOWER RANGE
MAXIMUM TORQUE
MAXIMUM HORSEPOWER

– 4 –
EH64D
2000 2400 2800 3200 3600
5
(6.7)
10
(13.4)
15
(20.1)
REVOLUTION r.p.m
HORSEPOWER
kW
(HP)
TORQUE
N-m
(kgf-m)
45 (4.59)
35 (3.57)
CONTINUOUS
RATED HP
RECOMMENDED
HORSEPOWER RANGE
MAXIMUM TORQUE
MAXIMUM HORSEPOWER

– 5 –
EH65D
2000 2400 2800 3200 3600
5
(6.7)
10
(13.4)
15
(20.1)
REVOLUTION r.p.m
HORSEPOWER
kW
(HP)
TORQUE
N-m
(kgf-m)
45 (4.59)
35 (3.57)
CONTINUOUS
RATED HP
RECOMMENDED
HORSEPOWER RANGE
MAXIMUM TORQUE
MAXIMUM HORSEPOWER

– 6 –
EH72D
2000 2400 2800 3200 3600
10
(13.4)
5
(6.7)
15
(20.1)
20
(26.8)
REVOLUTION r.p.m
HORSEPOWER
kW
(HP)
TORQUE
N-m
(kgf-m)
55 (5.61)
45 (4.59)
CONTINUOUS
RATED HP
RECOMMENDED
HORSEPOWER RANGE
MAXIMUM TORQUE
MAXIMUM HORSEPOWER

– 7 –
3. FEATURES
Highly rigid structure
●High-carbon steel, forged crank shaft
●Light-weight , tough alminum forged connectiong rod
●Ball-bearing
●Special cast iron cylinder liner
Long-lasting structure
●Forced pressure lubrication of crankshaft by directly connected trochoid pump
●Standard equipped oil cooler ensures a good lubrication environment
●Ball bearing installed in the throttle bearing of the carbureter
Reliability
●Unusually high dust proofing by a double compartment air cleaner and inner vent type carbureter
●Carbureter equipped with acceleration pump, and receives excellent throttle response.
●A fine distribution suction pipe and effective combustion chamber shape provide greater cubustion
stability and reduced gas emissions
Compact
●Center height 133.3mm and 25HP
●90°V2 cylinder built in crankcase

– 8 –
4. GENERAL DESCRIPTION OF ENGINE COMPONENTS
ROBIN EH63D/64D/65D/72D engine is air-cooled, 4-stroke, twin-cylinder, OHV arrangement gasoline engine.
The twin-cylinder is located in the angle of 90 degree; #1 cylinder is in the RH side and #2 cylinder in LH side
as viewed from flywheel (cooling fan) side.
4-1 CYLINDER AND CRANKCASE
The twin-cylinder and crankcase is single piece
aluminum die-casting.
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 BEARING COVER
The main bearing cover is an aluminum die-casting,
which is mounted on the output shaft side of the
crankcase.
Pilots and bosses are machined on the cover for
direct mounting of the engine onto such machines as
generators and pumps.
It is easy to inspect inside of the engine, after
removing the main bearing cover.
4-3 CRANKSHAFT
The crankshaft is forged carbon steel, and the crank
pin is induction-hardened.
The output end of the shaft has a crankshaft gear
pressed into position.
Engine oil passages are provided onto the journal
and pin portions of crankshaft for lubrication.

– 9 –
4-4 CONNECTING ROD AND PISTON
The connecting rod is forged aluminum alloy, and its
large and small ends function as bearings.
The piston is an aluminum alloy casting, and carries
two compression rings and one oil ring.
4-5 PISTON RINGS
The piston rings are made of special cast iron.
The profile of the top ring is barrel face and the second ring has a tapered face.
The oil ring is designed for better sealing and less oil consumption, in combination with 3 pieces.
4-6 CAMSHAFT
The camshaft is made of special cast iron and
camshaft gears are casted together in one piece.
Each 2 cam robs are provided for intake and
exhaust valves correspondingly.
Both sides of the shaft fit into the plane bearings on
the crankcase and main bearing cover.
TOP
RING
SECOND
RING
OIL
RING
1
2
3
BARREL
TAPER
COMBINATION
RING
1
2
3

– 10 –
4-7 CYLINDER HEAD
The cylinder head is an aluminum die-casting which
utilizes semi-spherical type combustion chamber for
the high combustion efficiency.
4-8 VALVE ARRANGEMENT
The intake valve is located on flywheel side of the
cylinder head.
The cooling fins and passages design lead cooling
air to the exhaust valve area for the optimum
cooling.
Hard alloy valve seats are molded in the cylinder
head.
INTAKE VALVEEXHAUST VALVE
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
inside of main bearing cover and driven by the
crankshaft.
GOVERNOR
GEAR

– 11 –
4-10 COOLING SYSTEM
The large fins on the flywheel provide sufficient
cooling air capacity for cylinder and cylinder head.
The cylinder baffle helps the cooling air flow
efficiently.
4-11 LUBRICATION SYSTEM
The engine is furnished with full pressure lubrication
system.
The trochoid type oil pump is driven by crankshaft
and delivers pressurized engine oil through the full-
flow type oil filter to the journal and pin portions of
crankshaft and camshaft.
4-12 IGNITION SYSTEM
The ignition system is a transistor controlled
magneto ignition system which consists of a flywheel
and an ignition coil with a built-in transistor installed
onto the crankcase.
FLYWHEEL
IGNITION COIL
CHARGE COIL
CABLE, EXTENDED
REGULATOR
CHARGE COIL
REGULATOR
4-13 CHARGING SYSTEM
Multipolar charging coil is provided inside of flywheel. Charging capacity is 12V-15A or 12V-30A.
(12V-15A) (12V-30A)

– 12 –
4-14 CARBURETOR
The engine is equipped with a down draft carburetor
that has a float controlled fuel system and a fixed
main jet.
The carburetors are calibrated carefully for the sure
starting, low fuel consumption and sufficient output.
Fuel cut solenoid valve is provided to prevent engine
running on when the key switch is turned to off.
Accelerator-pump is provided for obtaining quick and
good throttle response. (EH72D)
4-15 AIR CLEANER
The air-cleaner is a heavy-duty type with a dual
element system ; primary side is urethane foam
(half-wet) and secondary side is dry type.
ACCELERATOR-PUMP
FUEL CUT
SOLENOID VALVE
URETHANE FOAM
ELEMENT
WING NUT
CLEANER COVER
4-16 FUEL PUMP
The engine is equipped with a diaphragm type fuel
pump which is operated by the crankcase inside
vacuum pressure.
FUEL PUMP

– 13 –
4-17 SECTIONAL VIEW OF ENGINE
CARBURETOR
OIL PUMP
IGNITION COIL
FLYWHEEL
INTAKE MANIFOLD
OIL PUMP FILTER
MAIN BEARING COVER
P.T.O.SHAFT

– 14 –
AIR CLEANER
GOVERNOR LEVER
ROCKER ARM
CRANKCASE CRANKSHAFT CONNECTING ROD
PISTON PIN
PISTON
OIL FILTER
OIL COOLER
(EH72D)
PISTON RING
CAMSHAFT
PUSH ROD
INTAKE AND
EXHAUST VALVES
TAPPET
ELECTRIC STARTER
SPARK PLUG

– 15 –
5. DISASSEMBLY AND REASSEMBLY
5-1 PREPARATIONS AND SUGGESTIONS
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.
Have boxes ready to keep disassembled parts by group.
To prevent losing and misplacing, temporarily assemble each group of disassembled parts.
Carefully handle disassembled parts, and clean them with washing oil if necessary.
Use the correct tools in the correct way.
When disconnecting electric wirings, be sure to hold and disconnect the connector housing.
5-2 SPECIAL TOOLS
No Special Tool is needed for disassembling and reassembling the engine.
For pulling off the flywheel, universal type puller being popular in the market place as shown in the illustration
is needed.
FLYWHEEL PULLER
Tool No. Tool Use
228-95001-17 Flywheel puller with bolt EH63,64,65,72 / DY30,35,41,42

– 16 –
5-3 DISASSEMBLY PROCEDURES
Step Parts to remove Remarks and procedures Fasteners
1Engine oil drain Drain engine oil by removing plugs located
on both side of crankcase.
M14 x 12 Drain plug : 2 pcs.
2Muffler cover M6 x 14 Flange bolt : 4 pcs.
M6 x 8 Flange bolt : 2 pcs.
3Muffler M8 SUS Flange nut : 4pcs.
4Muffler bracket M8 x 20 bolt and
washer : 2pcs.
A
A
STEP 4
STEP 3
STEP 2
MUFFLER
BLACKET
MUFFLER
COVER
M6 FLANGE
BOLT
M6 FLANGE
BOLT
M8 BOLT & WASHER
M6 FLANGE BOLT
GASKET
MUFFLER
M8 SUS FLANGE NUT
STEP 1
GASKET
OIL DRAIN PLUG
(ON BOTH SIDE)
OIL FILLER CAP
OIL LEVEL GAUGE

– 17 –
BREATHER PIPE
WING NUT
STEP 5
CLEANER
COVER
CLEANER
ELEMENT
STEP 6
CLEANER BASE
HOSE CLAMP
M6 FLANGE BOLT
BREATHER PIPE
HOSE CLAMP
Step Parts to remove Remarks and procedures Fasteners
5Air cleaner cover and elements Remove cleaner cover and cleaner element.
6Air cleaner base Remove breather pipe from #1 cylinder head.
M6 x 12 Flange bolt : 3 pcs.