ROBIN AMERICA, INC. ROBIN TO W1SCONSJ.
CONTENTS Section Title 1.SPECIFICATIONS. ..................................................................................... 2.PERFORMANCE ........................................................................................ 1 3 3 2-2 3 2-3 ~~~i~~~ T~~~~~............................................................................... 3 2 - 4 performancecurves ........................................................................... 4 3.FEATURES .....................................................
1. SPECIFICATIONS EH30 Model EH30B EH30D EH30BS Air-Cooled.4-Cycle.Single-Cylinder,Horizontal Type I EH30DS P.T.O. Shaft, Gasoline Engine 78 X 61 m m (3.07 X 2.40 in.) Bore X Stroke 291 cc (1 7.76 cu.in.1 PistonDisplacement 8.3 CompressionRatio -~ output Cont i nuous 7.0/1800 HP/rpm 7.0/3600 HP/rpm Max. 9.0/1800 HP/rpm 9.0/3600 I Max. Torque 3-9/1250 kg Counterclockwise As ViewdFrom Direction of Rotation ~ kg m/rpm P.T.O. Shaft Side ForcedAirCooling Coolingsystem ~ 1.
EH34 Model EH348 1 EH34BS ~~~~~ Air-Cooled, 4- Cycle, Single- Cylinder, Horizontal Type Bore X Stroke EH340S EH34D P.T.O. Shaft, GasolineEngine 84 X 61 m m (3.31 X 2.40 in.) PistonDisplacement 338cc (20.63 cu.in.) CompressionRatio 8.3 Cont niw u s 8.0/1800 Max. 1 1.0/1800 output Max. Torque HP/rpm 4.82/1250 kg Direction of Rotation 8.0/3600 1 1.0/3600 HP/rpm m/rpm 2.41/2500 kg m/rpm Cooling ForcedAir ValveArrangement HP/rpm P.T.O.
2. PERFORMANCE 2 - 1 MAXIMUM OUTPUT The maximum outputistheoutput of anenginewithitsthrottlevalvefully opened under the condition that allthe moving partsareproperly worn in aftertheinitialbreakin period. A new engine may not producefullmaximum output while itsmovingpartsarestillnot broken -in.
2 - 4 PERFORMANCE CURVES OEHBOD, B Kg - m 9 8 7 6 CONTINUOUS RATED OUTPUT 5 4 RECOMMENDABLE \ 3 2 1 0 2400 2800 3200 3600 2000 (1 000) (1 200) (1 400) ( 1 600) (1 800) REVLOUTION- r. p. m.
*EH34D, B Kg - m w 3 0 HP A CONTINUOUS RATED OUTPUT RECOMMENDABLE HORSEPOWER RANGE 52B w cn 0 I 2000 2400 2800 3200 3600 (1 000) (1 200) (1 400) (1 600) (1 800) r. REVLOUTION- 5 - p. m.
3. FEATURES 1. The overhead valve design offers a compactness, light weight and ideal combustion charastristics resulting in more power from lessfuel and prolongedengine life. 2. Thevibrationfreedesignwiththetwinbalancersystemandlighterreciprocatingparts. 3. Such parts asthelargecapacitymuffler,dual element air cleaner,helical type balancergear of resinlaminated withextralongteethandthe blower housingand mufflercovermade "DAMPING SHEET" reduce noise to aminimum. 4.
4- 3 CRANKSHAFT Thecrankshaft is forgedcarbonsteel,andthe crank pin is induction-hardened. The output end of the shaft has a crankshaft gear and balancer gearthatarepressedinto position. (See Fig. 3.) B TYPE / D TYPE Fig. 3 4-4 CONNECTING ROD AND PISTON The connectingrod is forgedaluminum alloy, and small ends function as and its large bearings. The piston is an aluminum alloy casting,andcarriestwo compression ringsand one oil ring.(See Fig. 4.) Fig.
4- 6 CAMSHAFT Thecamshaft for the D- typeengineismade of specialcastironandcamshaftgearsare castedtogetherin one piece. Both sides of the shaft fit into the plane bearings on thecrankcaseandmainbearing cover. B- typeengineismade of Thecamshaftfor forged carbon steel and alsofunctionsas PTO shaft. ball Cam gear is pressfittedontheshaftand bearingsareemployedonthebothsidesfor supportingtheshaft. (See Fig. 6.1 I B TYPE Fig.
4- 9 GOVERNOR SYSTEM Thegovernor is acentrifugalflyweight type which ensures constant operation at the selected speedagainstloadvariations. is Thegovernorgearwithgovernorweights installedinthecrankcase and drivenbythe balancershaft. (See Fig. 9.1 Fig. 9 4- 10 COOLING SYSTEM Thelargefins on theflywheelprovidesufficientcoolingaircapacity areaandcylinder. Thecylinderbafflehelpsthecoolingairflowefficiently.
4- 12 IGNITION SYSTEM Theignitionsystem is atransistorcontrolled magneto ignition system which cosists of a flywheeland an ignition coil withabuiltin transistormountedonthecrankcase. This system has an ignitiontimingadvancefor easystarting. (See Fig. 11.) I Fig. 1 1 4- 13 CARBURETOR Theenginesareequippedwithahorizontal draft carburetor that has a float controlledfuel systemandafixedmain jet.
4- 15 BALANCERS Unbalanced inertia force is balanced by the two balancers which rotate at the samespeedwith thecrankshaft to effectivelyreducevibration. (See Fig. 14.) BALANCER 1 Fig. 14 4- 16 DECOMPRESSION SYSTEM An automaticdecompressionmechanismwhich AUTOMATIC DECOMPRESSOR SYSTEM opensexhaustvalvebeforethepistonreaches compression top is assembled on thecamshaft for easystarting. (See Fig. 15) Fig.
4- 17 SECTIONAL VIEW OF ENGINE FUEL 1 /FUEL ' FAN) FLYWHEEL (COOLING TANK MAIN BEARING COVER - 12 -
PLUG COVER ROCKER ARMS DRAIN PLUG \BALANCER - 13 - SHAFT 2
5. DISASSEMBLY AND REASSEMBLY 5 - 1 PREPARATIONS AND SUGGESTIONS 1) When disassemblingtheengine, memorize the locations of individualparts so thattheycan be reassembedcorrectly. If yor areuncertain of identifying some parts,itissuggestedthat tags be attached to them. 2) Have boxesreadytokeepdisassembed parts by group. 3) T o preventlosingandmisplacing,temporarilyassembleeach group of disassembed parts. 4) Carefullyhandledisassembedparts,andcleanthem with washing oil if necessary.
5 - 3 DISASSEMBLY PROCEDURES Step Part t o remove 1 Oil drain Procedures Remarks Tool (1) Remove oil drain plug and drain oil. (2) To discharge oil quickly, remove oil Be careful not to lose 14mm box wrench gauge. Fig. 17 - 15 - the gasket.
I Step Part to remove 2 Air cleaner Procedures Tool Remarks (1) Remove air cleaner cover. Be careful not to lose (2) Loosen twowing b o l t s and remove element. (3) Loosen screwon swivel and pull out choke knob. (4) Remove two flange nuts and a bolt and remove cleaner base. M6 flange nut 2pcs. M6 X 12mm bolt and washer * lpce. washer and gasket for wing bolt. .-.- Pull off breather pipe lonun box wrench from cleaner base. M6 FLANGENUT : 2pcs.
Procedures Step 3 Control panel and bracket (1) Unclamp wires from breather cover. (2) Disconnectwires from connectors. (3) Loosen two bolt andremove control panel. M5 X l O m m bolt and washer 2pcs. (4) Loosen. flange bolt and remove bracket. M6 x 8mm frange bolt * Ipse. 8mm box wrench -*.. ' 4 Carburetor Tool Remarks lorn box wrench - 0 . (1) Close fuel valve. (2) Disconnectfuel pipe from fuel strainer.
1 Step ]part to remove1 5 ~ ~ Speed contral lever and governor lever I Procedures (1) Unhook governor spring from governor lever. (2) Remove clip, wing nut, stop plate, friction plate, and speed control lever. (3) Loosen the bolt and remove governor lever. I Remarks I Tool Note governor spring hole on governor lever. ROD SPRING GOVERNOR LEVER I GOVERNOR SPRING 'ER Fig.
~~ Step F'art to rernovc I Procedures I Remarks main Be very careful not to damage stick and sensor unit in any way. Oil sensor bracket (Option) Removeoil Muffler (11 Loosen two flange nuts and a bolt. (2) Remove muffler and muffler cover from stud bolts. M8 flange nut 2pcs. M8 X 16mm bolt and washer lpce. Be careful not to lose muffler gasket. 6 Oil sensor (Option) Unclamp (1) sensor cord bearing cover. (2) Remove oil sensor unit. 7 8 from Tool I sensor bracket.
~ Electric starter (Option) I Procedures 'art to remove( Tool Remarks ~~~ ~~ (1) Remove black wire from electric starter. (2) Loosen two bolts and remove electric starter. M8 x 30mm bolt 2pcs. M8 washer 2pcs. M8 spring washer 2pcs. .*.- Reattach terminal nut to starter to keep it from missing. .......... 12mm socket wrench - Diode rectifier Magnetic switch (1) Disconnectwires. -........... green/white * * 2 white 1 (2) Remove diode rectifier and bracket from crankcase.
Step Part t o remove 12 Fuel tank Procedures Tool Remarks Loosen four flange nuts from bottom of fuel tank and remove fuel tank. M8 flange nut 4pcs. - 0 . - Wipe off thoroughly. spilt fuel 12mm socket wrench FUEL TANK FUEL STRAINER Fig.
Tool emarks Step Procedures Part to remove 13 Recoil starter 14 Remove Blower housing Remove recoil from blower housing. M6 X 8mm flange bolt 4pcs. lOmm box wrench blower housing from crankcase. M6 x 8mm flange bolt 4pcs. 1 O m m box wrench -- .-.- BLOWER HOUSING \ /1 Fig.
Ignition coil 15 Remarks Procedures Step Part t o remove Tool (1) Remove spark plugcap from spark Plug(2) Remove ignition coil from crankcase. M6 x 30mm bolt and washer * 2pcs. lOmm box wrench 1 . - ~ I ~~~ ~~ ~ Fuel tank Bracket Remove the fuel tankbracket M10 x 25mm bolt and washer Cylinder baffle Remove the cylinder baffle from cylinder. M6 x 8mm flange bolt lpce. I ~~ ~ ~~ ~~ ~~~~ ~ 14mm box wrench ..a- 4pcs. lOmm box wrench I I I SPARK PLUGCAP M10 FLANGE BOLT : 4pcs.
Step 18 'art t o remove Flywheel 19 (1) Remove nut from crankshaft. M16 nut lpce. (See Fig. 26.) (2) Remove thestarting pulley. M8 x 1 2 m bolt - * - - 3pcs. (3) Remove flywheel using flywheel puller. (See Fig. 28.1 (4) Remove thekeyfrom crankshaft. (SeeFig. 29.) Charge coil Tool Remarks Procedures Flywheel can easily be removed by striking the head of thecenter bolt of the flywheel puller with a hammer. 24mm socket wrench 12mm socket wrench Be careful not to lose the key.
I 1 Procedures eJ to Step \Part Remarks I Exhaust manifold Remove exhaust manifold and gasket from cylinder head. M8 flange nut 2pcs. 12mm box wrench Intake manifold Remove intake manifold and gasket from cylinder head. M8 x 28mm bolt and washer * * 2pcs. 12mm box wrench ---- -- Remove spark plug from cylinder head. I I Tool I I ,SPARK PLUG M8 FLANGE NUT : ZPCS. Fig.
'art to remove Cylinder head Procedures Remarks (1) Remove rocker cover from cylinder head. M6 x 12mm flange bolt 4pcs. (2) Loosen adjusting bolts on rocker arms. (3) Pull out rocker shaft from theintake side of the cylinder head. (See FIg. 31.) Tool 10mm box wrench .... Mark rocker arms and push rods so they be in their reinstalled original positions. (4) Remove the push rods from cylinder. (5) Remove cylinder head and gasket. M10 X 75mm flange bolt 4pcs. ..*.
r I Procedures Remarks (1) Pressdown spring retainer and slide it to releasefrom the groove of valve stem,thenremove spring retainer and valve spring.(See Fig. 32.) (2) Remove intake and exhaust valves fromcylinderhead. Put marks on valves, springs and retainers so they be reinstalled in their original positions. Clean carbon and gum deposit from the valves, valve seats, ports and guides. Inspect valves, valve seats and guides. Be careful of stem seal on intake valve.
Step Part to remove , 2 6 h4ai.n bearing cover Procedures Remarks (1) Remove bolts fastening main bearing , Be careful not to damage the oil seal. cover on crankcase. M8 x 4Omm bolt and washer *--*7pcs. (2) Remove main bearing cover from Use a soft hammer and crankcase. (See Fig. 35.) evenly tap around ~ outer surface of cover. I Fig. 35 MAIN BEARING COVER GASKET ‘ M8 BOLT AND WASHER : 7pcs. Fig.
27 Remarks Procedures Step Part to remove Camshaft and tappets (1) Remove camshaft from crankcase. (2) Remone tappets from crankcase. Balancer (I) Position piston at top dead center and removebalancer 1 and balancer 2. ~ c 1 28 ( I ) To prevent tappets from getting dynages , put crankcase cylinder side down. (See Fig. 37.) (2) Put marks on tappets to distinguish intake from exhaust. Fig. 37 Fig.
IStep I Procedures l ~ a r to t remove1 Remarks I ~~ 29 CoMfXthg rod and piston I I 30 I Piston and pistonpin (1) Remove connecting rod bolts and COMfXting rod cap. (2) Turn crankshaft until piston is at top dead center, push out connecting rod and piston assembly through top of cylinder. Scrape off all carbon might deposits that interfere with removal of piston from upper end of cylinder. (1) Remove clips Be careful not to give damages to piston and COMecting rod. Be careful not .
Procedures Step Part t o remove 31 Crankshaft Remarks lightly on flywheel end of crankshaft to move from crankcase. (See Fig. 40.) Tool (1) Tap t Fig. 40 f i g .
5- 4 REASSEMBLY PROCEDURES 0 PRECAUTIONSFORREASSEMBLY 1) Clean partsthroughly 2) 3) 4) 5) 6) 7) 8) beforereassembly. Paymost attentionto cleanliness of piston,cylinder,crankshaft,connectingrodandbearings. Scrape off allcarbondeposits from cylinderhead,pistontopandpistonring grooves. Check lip of oil seals. Replace oil seal if thelip is damaged. Apply oil tothelip beforereassembly. Replace allthegasketswith new ones. Replace keys,pins,bolts,nuts, etc., if necessary.
I ' "N" MARK .TOP RING .SECONDRING 'OIL RING fig. 44 Fig. 45 5 - 4 - 3 PISTON AND CONNECTING ROD When installingpiston on connecting rod on D type engine,match themark "DF"on thepiston DF"on connecting rod. with the mark On B type engine, match the mark "BF" on the piston with the mark " @ BF"on connecting rod. (See Fig. 46.) Oil small end of connecting rod before installing pistonandpiston pin. Use clips on the bothside of the piston pin to securepistonpininposition. "OF" A Fig.
(2) Installpistonandconnectingrodassembly into cylinder. Use a piston ring compressor to hold piston rings. The "DF"mark of theconnectingrod for "D"type engine or the "BF"mark for "B" type engine is to face flywheel side when assembled. (See Fig. 47.) PISTONRING COMPRESSOR CON,NECTlNG ROD \ -[NOTES] "-F 0 (1) Apply enough oil to piston rings, connecting rod bearings and cylinder bore before assembly. (2) Set gaps of the pistonrings 90 degrees apartfrom oneanother before assembly. (See Fig. 48.
5-4-5 BALANCER SHAFT Installbalancer shaft 1 (leftside)andbalancer shaft 2 (right side) to crankcase aligning matching marks of balancer gear and crank gear as shown in Fig. 50. Matching mark for balancershaft 1 is one dot andthat for balancershaft 2 is two dots. Align thesamemarks on balancer gearsand crankgear. (1) When installing balancer shaft 2, besure that governor gears mesh properly to drive gears on balancer shaft.
5 - 4 - 7 ADJUSTCRANKSHAFT AND END PLAY CAMSHAFT (1) Measure endplay of crankshaftandcamshaft. Adjustendplay tothe specified values using theproperspacer. CRANKSHAFT SPACER * Type D Type D Type B 0-0.2 mm 0-0.2 rnm T = 0.6 mm T = 0.8mm T = 1.O mm T = 0.6 mm T = 0.8 m m T = 0.6 mm T = 1:0 mrn T = 0.8 mrn SIDE CLEARANCE ADJUSTING CAMSHAFT Take the thickness the sideclearance. of GASKET,BEARING 0.1 3-0.29 Type 8 mm T = 0.7 mrn COVER intoaccount 0-0.2 rnm T = 0.6 mm T = 0.7rnrn T = 0.
(2) Lubricate oil sealandbearingsurfaces.Add a light film of oil onmain bearing cover face to hold gasketin place. (1) on crankshaftandcamshaft. Placespacerschosenatprocedure Use an oil sealguidewheninstallingmainbearing cover toavoiddamagingthe seal. Tap cover into place with a soft hammer. 7 pcs. Main bearing cover M8 X 40 mm bolt and washer * * * e Tightening torque 170-190 kg * c m 16.7-1 8.6 N m 12.3-L.13.
5 - 4 - 11 VALVE CLEARANCE ADJUSTMENT (1) Position piston at top dead center of compression stroke by matchingthemark of flywheel with the mark T of crankcase. (See Fig. 53.) (2) Loosen lock nut on rockerarm and turn adjusting screw to adjust the clearance betweenrockerarm and valve stemend. (See Fig. 54.) Tighten lock nut. Fig. 53 - [NOTE] Check and adjustvalveclearance cold. of valves Check operation crankshaft . Remeasure tappet clearance. with engine turning by (3) Installrocker cover andgasket.
(1) Installcharge coil to crankcase. Clamp coil wire to crankcase. [NOTE] -I coil Be careful not t o pinch charge coil and crankcase. wire between (2) Put woodruff key in keyway of crankshaft. Wipe off oil andgreasethoroughlyfrom taperedportion of crankshaftandflywheel center hole. (3) Installflywheel to crankshaft. Tightenflywheel nutwithspring washer. (See Fig. 55.) Fig. 55 Tightening toque 83.4-93.2 N m 850-960 kg cm 61.5-68.7 ft Ib (4) Install starting pulley to flywheel.
5-4-18 FUEL TANK Install fuel tank to fueltank bracket. 5 - 4 - 19 ELECTRIC STARTER (Optional equipment) (1) Installmagnetic switch tocrankcase. (2)Install diode rectifiertocrankcase. (3) Installelectric starterto crankcase. (4) Connect wires referringtothe wiring diagram. 5-4-20 MUFFLER hstallmufflertoexhaust pipewithmuffler gasket. 5-4-21 OIL SENSOR (Optional equipment) (1) Install sensor bracketto crankcase. (2) Install oil sensor unit to sensorbracket.
(5) Installcarburetortointakepipe hooking governorrod to governor lever and throttle lever of carburetor. Hook rod springover governor rod. (See Fig. 59.) (6) Attachpanelbracketandair cleanerbase tocarburetorwithgaskets. Tightentwoflangenuts and abolt. Connect breather pipe from tappet cover to cleaner base. (7) Adjustgovernorsystem. (a) Push speedcontrollever all the way to thehighspeed position and fix itby tighteningwingnut. (See Fig. 60.
(8) Installcontrolpanel to bracket. Connectwires. (9) Put chokeknobwire throughgrommet on cleanerbase andfasten of carburetor. (10) Putelementintoair cleaner andfastenwithwing bolts. Installair cleaner cover. - End of the reassembly - to swivel on chokeshaft 5 - 5 BREAK- IN OPERATION been completelyoverhauled by beingfittedwith a new piston,rings,valves put back intoservice.
6-2 B A S E THEORY (1) Revolution of theflywheelgenerateselectricity on theprimary side of theignition coil, and thebasecurrent I1 flows tothe power transistor. Iz flows. Current I1 turnsthe power transistor"0N"andtheelectriccurrent (2) At lower engine revolution, when the flywheel reached the ignition point the low speed ignition timing controll circuit operates to run the base current 13 to turn the signal transistor A "ON" allowing thecurrent I1 tobypassascurrent 14.
6-3 WIRING DIAGRAM STANDARD Stop Button c Ignition Coil Connector I -1 Black Spark Plug " 775-. ! Flywheel ElNGlNE WITH ELECTRtC STARTER I I I I I I I I I I I I l - I I I I I I I I \ L """""""- DIODE RECTIFIER II I r 1 Fig. 63 - 44 - 1 2VOLT BATTERY MINIMUM 24 AMP.HR.
7 . AUTOMATIC DECOMPRESSION SYSTEM The decompression systemoperatestorelease compression by liftinguptheexhaust valve at starting. The releaselevermounted on thecamshafthas a flyweight a t one endandacrescent cam at theother end. When startingthe engine,thecrescent cam juts outfromtheexhaust cam. The exhaust tappet rides over the crescent cam opening the exhaust valve to release compression. LEVER CRESCENT EXHAUST Fig.
8.CARBURETOR 8- 1 OPERATION AND CONSTRUCTION 8 - 1 - 1 FLOAT SYSTEM The float chamber is located below the carburetor a needle valve, body and, with float a and maintains a constant fuel level during engine operation. (See Fig. 66.) The fuel flowsfrom the fuel tank into thefloat chamber through needle valve. When the fuel rises to aspecificlevel,thefloatrises,and when its buoyancy and fuel pressure are balanced, the needle valve closes toshut off the fuel, thereby keeping the fuel atthepredetermined level.
8-1 - 2 PILOT SYSTEM The pilot systemfeedsthe fuel totheengineduringidlingand low- speedoperation. jet tothepilotjet,where it is metered,and mixed with the Thefuel is fedthroughthemain airmetered by the pilotairjet. Thefuel-airmixtureisfedtothe engine throughthepilotoutletandthebypass. Atidlingspeed,thefuelis mainlyfed fromthe pilot outlet. 8 - 1 - 3 MAIN SYSTEM The main systemfeedsthefueltotheengine a t medium- andhigh-speedoperation. Thefuel is metered by themainjetandfedtothe main nozzle.
8 - 2 - 4 MAINSYSTEM (1) Remove thebolt(12)andtakeoutfloatchamber body (13). (2) From the body (14) remove the main nozzle (15), andthen remove the main jet (16) and guideholder (17) from the main nozzle (15). (3) Reassembly a) Fasten the main jet securely to the body. Otherwise, the fuel may become too rich and cause enginemalfunction. b) Thebolt tightening torque is 70kg - cm.Be sure to set the gasket (19) and washer (18) for chamber ( 13).
9. STARTING SYSTEM 9-1 RECOIL STARTER When repairing recoil starter,disassembleand reassemblein Tools : Socketwrench, Needle nose pliers,Screwdriver the followingprocedures. [NOTE] The following explanation is applicable tothe recoil starter for “D” type engines. For “B” type models, reverse the direction of rotation t o achieve proper service work. 9-1 - 1 HOW TO DISASSEMBLE (D Type) (1) Remove recoil starterfrom engine.
(4) Remove reelfromstarter case asshown in Fig. 71. Take out reel slowly turning it lightly toward left and right to remove spring from the hook. Do not remove thereelquickly or the spring may escape from thestarter case. Untie starter rope from the knob and remove. p g ' STARTER CASE Fig. 71 9- 1 - 2 HOW TO REASSEMBLE (D Type) ( 1 ) Putstarter rope through starter knob and tieitasshown in Fig. 72. (Tie therope tightlyforthesafety sake.) of the rope through Puttheoppositeside starter case and reel.
(3) Prior to installing reel in starter case, wind starterropeinreelfor 2.5 turns in the arrowheaddirectionas shown in Fig. 74. Then let the rope out of reel from the notch on reel. Line upthe hook withinner end of springandinstallreelinstarter case. Check that the inner end of spring is securelyhookedontothe hook. (4) Reassemble parts reverse in order of disassembly. Check thatratchetsare pushedbyratchet of recoil.
(6) Testoperation of recoil starterto see if rope recoils satisfactorilyandratchetsprojectand retract properly. Mount recoil startertotheengine. (7) If spring escapesfromreelwhendisassembling notch of reel and rewind thespringintothe recoil, hook theouter housing. end of springontothe or mobile (8) Lubricatetherotatingparts,slidingpartsandspringwithheatresistantgrease oil whenreassembling recoil and priorto long termstorage.
(4) The rear cover Remove the rear cover. 4 Fig. 79 (5) The 4mm screws (2pcs.I (6) The brush holder. (7) "M" terminalbush No, 2. The brush holde is disassembled by remov,ing the 4 mm screws. (Zpcs.) Remove the "M" terminalbush No, 2. 6 Fig. 80 (8) Yoke assembly. Remove the yoke assembly. f i g .
(9) The pinion stopper clip. The pinion stopper clip is removed with a standard screwdriver while the pinion stopper is pushed toward the pinion. Fig. 82 (1 0 ) Pinion stopper. (I 1) Pinion return spring. (1 2) Pinion assembly. The pinion stopper, pinion returnspring and the pinion assembly can be dis assembled once the pinion stopper clip has been removed. 12 \ 11 Fig. 83 - (13) Armature. (14) Thrustwashers (4pcs.) (15) Front cover. The armature, thrust washers (4pcs.).
\L 9 11 15 12 13 14 I 14 '2d 3 2 0 nlmml 9 5 8 6 \ 4 Fig. 85 1. 2. 3. 4. 5. 6. 7. 8. The 6 m m terminalnuts (2pcs.) "M" terminalbush No,1 The5mmthroughbolts (2pcs.) The Rear cover The 4 m m screws (2pcs.) Thebrushholder "M" Terminal bush No, 2 Yokeassembly - 55 - 9. The pinion stopper clip 10. Pinionstopper 1 1. Pinion return spring 12. Pinionassembly 13.Armature 14. Thrustwashers(4pcs.) 15.
9 - 2 - 2 INSPECTION AND REPAIR ( 1 ) ARMATURE a) Check thediameter of thecommutator. If theoutsidediamaeter of thecommutator is below the minimum Iimit then replaceit. Unit : mm I Standard (New) 30 I (Used) Limit I 29 Fig. 86 b)Continuitytest for thearmature coil. Use a tester to check for continuity between parallel points on the commutator. If There is continuity, the armature is still good. No continuity : (Disconnected coil) Replace thearma ture. TESTER Fig.
d) Check for Surface Distortion on the Armature and theCommutator. Use a dial gauge to measure the distortion of theout side surfaces of thearmature core and the commutator. If it is above the limit,thenrepair or replace it. Q0 COMMUTATOR Unit : mm I I Armature Commutator I Standard (New) I I 1 0.05 (Max.) 0.05 (Max.) [ 1 Limit (Used) 0.1-( M a x 7 1 OK (Max.) 1 I Fig. 89 e) Check theSurface of theCommutator.
(2)BRUSH Measure thelength theyareunderthe of thebrushesand limit, replacethem. if Unit : mm Brush Positive side brush Negative side brush Fig. 92 (3)BRUSH HOLDER a>InsulationTestfortheBrushHolder. Check forcontinuity between thebrush holder'stop(Positiveside)anditsbase (Negativeside). If there is no continuity then i t is still good. Continuity Exists :(Unsatisfactory Insulation) Replace the brush holder. Fig. 93 b) Inspection of the BrushSprings. Check the weight of thebrushsprings. I Fig.
(4) PINION CLUTCH Inspection of the pinionclutch. Rotatethepinionmanually. While rotating it in the direction of normal operation, smoothlyreversethedirection of rotation to confirm that it locks. In theevent of any irregularity,replace it. Fig. 95 9-2-3 REASSEMBLY Reassembly is intherevrseorder of disassembly,howeverpleasenotethefollowingpoints. (1) ThePlacesto Apply Grease : Theslidingsurfaces of thepinionandthe shaft’sspline. Themetalsholdingtheshaft atthefrontandrearcovers.
10. TROU8LESHOOTtNG The following threeconditiontsmust be fulflledforsatisfactoryenginestart. 1. Thecylinder filled with aproperfuel-airmixture. 2. Good compressionin thecylinder. 3. Good spark,properlytimed,toignitethemixture. Theenginecannot be started unless thesethreeconditionsare met. Therearealsootherfactors start difficult,e. 8.. a heavyloadontheenginewhen it isabouttostart which makeengine at low speed,and a highbackpressuredue to alongexhaust pipe.
10- 1 - 3 IGNITION SYSTEM Check thefollowingsforlack of sparks. (1) Wires of theignition coil, sparkplugorcontactbreaker (2) Ignition coil damagedandshorted. (3) Spark plug cablewetorsoakedwith oil. (4) Sparkplugdirtyor wet. (5) Sparkplugelectrodegapincorrect. (6) Sparkplugelectrodesareconnected or bridged. (7)Incorrectsparktiming. disconnected. 10- 2 ENGINGE MISFIRES (1) Incorrectsparkplugelectrodgegap.Adjust (2) Ignitioncablewornandleaking. (3) Sparks weak. (4) Ignition wire connections loose.
10-5 ENGINEKNOCKS (i) Poor quality gasoline. (2) Engine operatingunder heavy load at low speed. (3) Carbon or lead deposits in thecylinderhead. (4) Spark timing incorrect. (5) Loose connectingrodbearingdue to wear. (6) Loose piston pin due to wear. (7,) Cuases of engine overheat. 10- 6 ENGINEBACKFIRESTHROUGHCARBURETOR (1) Water or dirt in gasoline, or low- grade gasoline. (2) Intakevalvestuck. ( 3 ) Valves overheated, or hotcarbon particles in the combustionchamber. (4) Engine cold.
11. INSTALLATION Enginelife,ease of maintenanceandinspection,frequency of checksandrepairs,andoperating on the way in which theengineisinstalled. Review the following instructions costalldepend carefullyforinstallingthe engine. 11 - 1 INSTALLING When mounting the engine, carefully examine its position, the method of connecting it to a machine, thefoundation, and the mehtod of supportingtheengine.
12. SERVICE DATA 12- 1 CLEARANCE DATAAND LIMITS Unit : mm (in) T ITEM ~EH%/EH34 i Limit CYLINDER HEAD Flatness 0.05 (0.002) Valve seatcontact 0.1 (0.004) width IN. EX. 0.7-1 .O (0.028-0.039) 2.0 (0.079) 6.600-6.622 (0.260-0.261 6.75 (0.266) Valveguideinsidedia.
Unit : mm (in) I I CYLlNDER 0 Inside dia. STD I EH30 STD Lmit EH34 SBD To be rebored the when difference 78.000-78.01 9 betweenmax. 84.000-84.022 and min. of (3.307-3.308) (3.071 "3.072) diameter reached to 0.1 Lmit To be rebored when the difference between max. and m i no. f diameter reached t o 0.1 (0.004). (0.004). I 1s t reboring 2nd reboring Roundinessafter 8 Cylindricity after 78.250-78.269 (3.081 -3.082) Ditto 78.500-78.51 9 (3.091 -3.092) 84.250-84.272 (3.31 7-3.31 8) Ditto 84.
Unit : mm (in) EH30 ITEM STD Ringgroovesideclearance TOD 2nd Oil ring EH34 Limit STD Limit 0.1 5 (0.006) 0.05-0.09 (0.002-0.0035) 0.1 5 (0.006) '0.0012-0.0028: 0.1 5 (0.006) 0.93-0.07 0.0012-0.0028> 0.1 5 (0.006) 0.01-0.065 :0.0004--0.0026: 0.1 5 (0.006) 0.01-0.065 0.0004-0.0026: 0.1 5 (0.006) 20.995-21.008 '0.8266-0.8271: 2 1.035 (0.8281 20.995-21.008 0.8266-0.8271 2 1.035 (0.828 1 20.99 1 " 2 1 .OOO :0.8264--0.8268: 20.960 (0.8251 ) 0.8264-0.8268; (0.825 1 ) U.rJ25."-,0.
Unit : mm (in) 1 STD Limit CONNECTING ROD Big endinside dia. 38.000-38.01 6 1 -4967) ( 1 -4961 - Clearance between big end andcrankpin 0.030-0.060 (0.00 12-0.0024) 0.2 (0.0079) 21.010-21.023 (0.8272-0.8277) 21.080 (0.8299) 0.01 0-0.032 (0.0004-0.001 3) 0.1 2 (0.0047) Small end insidedia. Clearance betweensmall pin endandpiston Big end side clearance 0.1 -0.3 (0.0039-0.01 18) 1.O (0.0394) I CRANKSHAFT 37.956-37.970 (1 -4943- 1.4949) 34.986-34.997 (1.3774- 1.
Unit : mm (in) I T ITEM EH30/EH34 STD Limit CAMSHAFT 0 36.1 "36.3 (1.4213-1.4291) 35.95 (1.41 54) 19.967- 19.980 (0.7861 -0.7866) 19.950(0.7854) IN. 6.535-6.550 (0.2573-0.2579) 6.450(0.2539) EX. 6.522-6.544 (0.2568-0.2576) 6.450(0.2539) IN. 0.050-0.087 (0.0022-0.0034) 0.30 (0.01 1 8) EX. 0.056-0.1 00 (0.0022-0.0039) 0.30 (0.01 18) IN./EX. (cold) 0.085-0.1 15 (0.0034-0.0045) Cam height IN.EX. cams VALVE * Valve stem outside dia. Clearance between valve stem dia.
ITEM Unit : mm (in) r 1 EH30/EH34 STD Limit TAPPET 0 Stem outside dia. 8.960-8.975 (0.3528-0.3533) 8.93 (0.351 6) 9.00-9.01 5 (0.3543-0.3549) 9.08 (0.3575) Guide inside dia. 0 Tappet guide clearance 0.025-0.055 (0,001 0-0.0022) 0.15 (0.0059) ROCKER ARM Rocker armhole Rocker armshaft 1 1.986-1 1.994 (0.471 9-0.4722) 1 1.92 (0.4693) 1 2.006- 1 2.024 (0.4727-0.4734) 12.07 (0.4752) dia. clearance 0.01 2-0.038 (0.0005-0.001 5) VALVE SPRING FREE LENGTH 39.5 (1.5551 ) - 69 - 0.
Unit : mm (in) EH30/EH34 ITEM STD Limit VALVE SEAT ANGLE (IN. EX.) 0 Valve cutter angle (a) width (b) 0 Valve contact a : 90" b : 0.7-1.0 2.0 (0.079) (0.028-0.039) 12- 2 TORQUE SPECIFICATIONS ~ ~~~ TIGHTENING TORQUE DESCRIPTION kg ~~ cm ~~ I N m I f t Ib Cylinder head bolts 340-420 Connecting rod cap bolts 225-275 22.1 -27.0 16.3- 19.9 850-950 83.4-93.2 61.5-68.7 170- 190 16.7-18.6 12.3-13.7 New spark plug 120-150 11.8- 14.7 8.7- 10.9 Retightening 230-270 22.6-126.
12-3 OIL GRADE CHART t Comparison between oil viscosity and temparature Specified Lubricant Single grade aualitv Multigrade - 20 - 10 -4 0 32 14 10 50 20 68 30 86 Use oil classified as SC or higher. Multi-grade oil tends to increase its consumption at high ambienttemperature.
13. MAINTENANCEAND STORAGE The following maintenance jobs apply when the engine is operatedcorrectlyundernormal conditions. Theindicated maintenance intervalsareby no means guarantees for maintenance free operationsduringtheseintervals. Forexample, if the engine is operatedinextremelydustyconditions,theaircleanershouldbe cleaned everydayinstead of every 50 hours. 13- 1 DAILYMAINTENANCE REMARKS MAINTENANCE 1) Clean away dust and chaff from engine. Governor linkage is especially sensitive to dust.
13-4 EVERY 1O Q " 2 8 0 HRS. (MONTHLY) MAINTENANCE I REMARKS ~~~ ~ 1) Clean fuelfilter and fueltank. Remove blower housing and clean up between fins and housing. 2) Inspect cooling system and remove dirtand chaff. 43-5 EVERY 500-600 I I HRS. MAINTENANCE MAINTENANCE I head. I REMARKS I power. 2) Disassemble and clean carburetor 13- 6 EVERY 1000 WRS. (YEARLY) MAINTENANCE I I I REMARKS MAINTENANCE 1) Overhaul engine. 2) Replace fuel lines once ayear. I Clean andcorrectparts.
Industrial Engines
