manuals.online logo
Brands
  1. Home
  2. •
  3. Brands
  4. •
  5. Saito
  6. •
  7. Engine
  8. •
  9. Saito FG-40 User manual

Saito FG-40 User manual

SwitchCapacity:3A~
Sensor Battery
Voltage:6-12V
Capacity:1,000mA〜
Plugcap
(2)Sensorcord
(Black)
(1)Plugcord
Mainunit
(3)BatteryCord
(Red/Black)
(4)Tachometercord
FG-40InstructionManual
Fueltank FuelLevel
ToOutsideoftheplane
Ventline
fuelsupplytocarburetor
Fuelfillerline
Ventline
Gasoline-compatible
tankstopper
Gasoline-compatibletubing
Filterwithweight
Closeaspossible(within200mm)
Hollowout
oradjustusingthe
mountspacers(option)
Firewall
Enginecenter
Throttlelever
Slowneedle
CCW
torich
CW
tolean
CCW
torich
CW
tolean
Mainneedle
1.Fuel
●Thefuelisamixtureofcommercialregulargasolineandreliableoilfor2-strokeengines.
●[Exampleofoilrecommendation]
・KlotzKL-200OriginalTechniplate・DeluxeMaterialsPowerModel2T-S・ENEOSRACINGSPECPRO-2T(SAITOSTANDARD)etc.
Ifsuchoilsarenotavailableinyourcountry,thenpleaseasktheofficialSAITOdistributorinyourcountryforanalternative.
●Besuretousethemixture“gasoline:oil=15~20:1”byvolumeratio.(Ex.1000mlofgasolineshouldbemixedwithmorethan50mlofoil).
●InBreak-inprocess,use15:1mixedfueltoensurethebestlubricationforinitialrun.
●Anydamagecausedbythefuelused,inwhichtheoilratioislowerthan20:1ratio,isnotwarranted.
●Donotusegasolineethanolmixed.Itmaycausenotonlypowerlossbutalsocorrosioninsidetheengine.
Φ40.0mm 32.0mm 40.2cc
19”x10”~21”x8”
・Filterwithweight[G36-154] ・DurabletubeforGasoline(1m)[G36-155] ・Mountspacer[G40-169]
・Aluminumspinnernut[120S-30] ・Tappetadjustingkit[120S-161]  ・Digitaltachometer[G17-167]
Bore
Mainbody:1,260g/Muffler:90g/Ignition:100g
Stroke Disp.
Weight(Approx.) Practicalspeed Approx.1,800-8,000rpm Maxonground Approx.6,500-7,500rpm
Propeller CM-6Plug
Optionalparts
4-strokeglow200classApplications
Batteryforignitionsystem
・Limitgauge(0.1t)fortappetadjustment1pc ・Wrenchfortappetadjustinglocknut1pc ・Carburetoradjustmentbar 1pc
・Sparkplug[CM-6](Attachedtotheengine)1pc ・Mufflerset  1set ・Chokebar  1pc
・Ignitionsystem(w/sensor) 1set ・Plugwrench   1pc ・Enginemountset 1set
・Anti-looseningnut 1pc ・Hexagonalwrench  1set
Specifications
Standard
accessories
Voltage:6-12V,greaterthan1,000mA ※
※IfyouuseaLi-Po,werecommendthespeclessthan2,500mAcapacityand
 lessthan30Cdischargerate
2.Ignition
●Placethemainunitasfarfromotherelectricaldevicesaspossible.
●PlacethetwoswitchesoftheignitionandtheRCreceiverasfar
fromeachotheraspossible.
(1)Plugcord(meshedhightensioncord)
Insertthecapdeeplyontotheplugtomakesureitwillnotcomeoff.
(2)Sensorcord
Connectwiththecordfromthesensorattachedtotheengine.
(3)Batterycord(black/redcord)
Useafullychargedbatterythathasadequatespec.(6-12V,more
than1000mAisrecommended.).Betweenthebatteryandmainunit,
makesuretoinstallaheavydutyswitchwhosecapacityishigher
than3A.
(4)Tachometercord(optional)
Connectthedigitaltachometer(Option).Otherwisetheconnectorisnormallyvacant.
4.Methodofchoke(Noneedwhenyouusestarter)
※Chokingisthemeansbywhichfuelisfedtotheenginewhenyoustartitbyhandflipping.Thusitisunnecessarywhenusingstarter.
Startingwithaelectricstarterisrecommendedforsafety.
●Inadvance,makeathinholeinthecowlingtoinsertthechokebar/slowneedleadjustmentbar.
●Duringchoking,besuretoturnofftheignitionswitch.
●Asshowninthefig,passthechokebar(withM3.5threadonitstip)throughtheholein
thecowling.ThenturnthebartoinsertintotheM3.5internalthreadatthecenterofthe
throttlelever.
●Fullyclosethethrottleandpullthechokebarandfixitwithacliporclampasshownin
thefigsothatitmaynotgobacktothepreviousposition.
●Graspthepropbyhandandturnitseveraltimesinthedirectionofnormaloperation
(CCW)untilthecarburetorgenerateshissing-likesound.Afterhearingthissoundfor
about5times,quicklyflipthepropapproximately10times.
●Removethechokebar.Thenpowerontheignitionsystemandflipthepropquicklyto
starttheengine.Iftheenginedoesnʼtstart,repeatthechokingprocedure.
3.Propeller
●TheStandardpropisMejzlikD20”xP8”whichbringsapprox.6,900rpm(orFalconD20”xP8”bringsapprox.6,400rpm).
Largersizeorgreaterpitchcancauseenginebrokenduetooverload.
●Useawell-balancedone.Neverusethepropellerthathasbeenscratchedordamagedevenifslightly.
●Asthepropelleriscompressedslightly,tightenthepropellernuteveryhourofoperation.
Cowling
Chokebarforinsert
M3.5screw
Throttlelever
Throttlevalve
(Movetotheleft)
Slowneedle
Chokebar
Temporaryfixed
byaclip
ver.Feb,2021
5.Break-inMOSTIMPORTANT!!
●Prop-recommendation:20”x8”carbonpropforbreak-in.
●Use15:1fuel:oilratioforbreak-in.
●NevermakethefuelmixtureleanduringBreak-in.Itcouldcauseseizureevenduringidlingorlowspeedrunning.
●Beforestartingtheengine,openthemainneedleApprox.3turnsandslowneedleApprox.5turnsopen(CCW)fromfullyclosed.
●Starttheengine(usingastarterisrecommendedforsafety).
●Soonafterstarting,Openthethrottlegraduallyuptofullopen.InthemeantimeturnthemainneedleCCW.Continuetoturnthemain
needleCCWuntiltheRPMdeclines(toapprox.4,000rpm),keepingthethrottlefullyopened.
●IfopeningmainneedledoesnʼtdropRPM,thenopentheslowneedletoo.
●Runinthisveryrichconditionfor1literoffuel.
●Now“initial”break-inisdone.
6.Adjustmentofcarburetorafterinitialbreak-in.
◇Needlereferenceposition(Setafterinitialbreak-in)
●Starttheengineafteradjustingtheneedletothefollowingreferencevalue.
●Mainneedle:Approx.2~2.5turnsCCWfromfullyclosed
●Slowneedle:Approx.4.5~5turnsCCWfromfullyclosed(Thenthrottleshouldbefully
closed)
●Actually,thebestpositionoftheneedlesvarydependingontheprop,temperature,
humidityandsoon.Pleaseadjustasnecessaryafterobservingtheengineperfor-
manceduringflight.
◇Peakadjustment
●Afterstartingtheengine,warmupforapprox.30secondsatlowspeed.
●Achievethepeakatfullthrottle.
→TurnthemainneedleCWgraduallytothepositionwheretheRPMisgreatest(thepeak).ContinuingtoturntheneedleCWpastthe
peakcouldleadtoseizuresoturnitslowlyandcarefully.IftheRPMsuddenlydecreasesafterpassingthepeak,instantlyturnthemain
needleCCWtoagainincreasetheRPM.Otherwiseitcoulddamagetheengineseriously.
●OnceachievingpeakRPM,returnthethrottletolowspeed.Makeanoteofthepositionofmainneedleatthepeakatthattime.
(HowmanyturnsyoudidCWbasedonthereferencevalue.)
◇SlowneedleAdjustment
●AfterachievingpeakRPM,nextisslowneedleadjustment.OpenthethrottlefromlowRPMtofullthrottlequickly.
●IftheenginehesitatesforamomentorstallsbeforetheenginereachesmaxRPM,Itʼsbecausethemixtureistoolean.Thenturntheslow
needleCCWslightly.
●IftheengineisslowtoreachpeakRPM(fullthrottleset),itʼsbecausethemixtureistoorich.ThenturntheslowneedleCWslightly.
●AdjusttheslowneedleasaboveuntiltheRPMfollowsthethrottlemovementsmoothly.Theimportantpointistoadjusttheslowneedle
AFTERthemainneedlehasbeenadjustedtoitspeak.
●Nowbreak-inatgroundlevelisdone.Adjusttappetsbythemethoddescribedlater.
◇Pre-flight/Flightadjustment
●Whentheslowneedleadjustmentisdone,checktheresponsebyrevvingupfromlowspeedtofullthrottlequicklyseveraltimes.
●OpenthethrottlefullyandturnthemainneedleCCWapprox.60〜90degreesfromthepeakposition.Thisistomakethefuelmixture
richerintheairwheretheRPMgethigherthanontheground.
●Afteralladjustmentsaremade,flyyouraircraftandfinetunetheengineaccordingtothesituation.Basicallytuningshouldbedonewith
themainneedle.Readjustmentoftheslowneedleisrarelyneededifthefirstadjustmentoftheslowneedlehasbeendonesuccessfully.
7.Tappetadjustment
Thevalveclearanceshouldbecheckedandadjustedafterbreak-inandeverytimeaftertwohourswhiletheengineiscold.Beforeadjusting
tappetgaps,tightenupthescrewsaroundcylindersetc.
2.Loosenthelocknutandadjust
thegapbyhexagonalwrench
untilyougetthecorrectgapfor
bothofintake&exhaust.
3.Oncethegapisset,tightenthe
locknutandattachtheplugand
covers.
4.Turnthepropbyhandtocheckifthe
compressionisenough.Ifthegapisless
than0,thevalveisalwaysopened
slightlyandwilllosecompression.Then
adjustagain.
1.Removethesparkplugandrocker
armcoversofthecylinder.Then
turnthepropCCWbyhandto
placethepistonatTDCof
compressionstroke.
CorrectGap
Mustnotbeinserted
Closeto“0”withnolimit
Limitgauge
(0.1mm)
Loosenthelocknut
Adjustthegapturning
thesetscrew
TopDeadCenter
(bothvalvesareclosed) Tightenthelocknut
tofixthesetscrew
Note:
●Asitusesoil-mixedfuel,theplanemaysometimesgetdirtyfromtheexhaust.
●Useareliableandwell-balancedprop.Otherwiseitmaycauseanabnormalvibrationandcouldresultinaseriousaccident.
●Duringoperation,allenginescrewscanloosenduetometalheatexpansion.Checkandtightenoccasionally.
●Whentheexhaustvalvegetsdullbycarbonorsludgeespeciallyincoldatmosphere,removetherockercoverandapplysomeanti-rust
spraytotheexhaustvalvetohelpthevalvetomovesmoothly.
●Payattentiontothesurroundingssoasnottodisturbothersbynoiseandexhaust.
●Alwayskeepspectatorsbehindtheenginewhenoperatingtheengine.
64
129
28
M8x1.25
69
86
70
54
27
4-Ø4.3
35
35
71
155.5
84.5
44 16
30
Outsidedimensions
●Asexhaustsmokeisharmful,becarefulnottobreatheinorotherwiseexposeyourselftoitsharmfuleffects.
●Payattentionnottotouchtherotatingpropellerwhenstartingengine,andmovetorearsideoftheaircraftoncetheengineisstarted.
●Allresponsibilitiesfortheuseoftheengine,andotherobligationsandresponsibilitiesbasedonlaws,regulations,etc.arebornebythe
purchaserandtheuser,andSAITOSEISAKUSHOCO.,LTD.isexemptfromanyresponsibilities.
Warranty:
●Ifthereisanydeficiencyfromthefactoryconcerningmanufacture,pleaseconsultwiththeshopordistributoryouboughtfrom.Our
companywillberesponsibleforrepair.However,anyfailureortroublecausedbyunnecessarydisassembly,modification,orotherusesthan
thoseprovidedintheinstructionmanualisnotsubjecttowarranty.
●Ignitionsystemissubjecttothewarrantyonlyforinitialfailure.Oncethesystemhasbeenactivatedsuccessfully,itwillnolongerbesubject
towarranty.
SAITOSEISAKUSHO,CO.,LTD.www.saito-mfg.com
22-7,3-chome,Tokagi,Ichikawa-shi,Chibaprefecture272-0024,JapanPhone:047-378-4156FAX:047-378-4155
Allspecificationsandmodelsaresubjecttochangewithoutnotice.
FG-40PartsList
No.
01
06
07
08
09
10
14
15
17
19
20
22
23
27
28
31
32
33
35
36
37
38
39
40
41
42
Qty
1
1
1
2
1
1
1set
1
1
1
1
1
1
1ea.
1ea.
1set
1set
1
1
1
1set
2
2
2ea.
2
2ea.
Item
Cylinder
Piston
Pistonpin
Pistonpinretainer
Pistonring
Connectingrod
Cylinderscrewset
14-1,-2,-3,-4
Crankcase
Rearcover
Breathernipple
Frontballbearing
Rearballbearing
Crankshaft
Tapercollet&driveflange
27-1,-2
Propwasher&Nut
28-1,-2
Crankcasescrewset
31-1,-2,-3
Enginegasketset
32-1,-2,-3,-4.-5.-6.-8
Camgearhousing
Camgear
Camgearshaft
Steelwasherset
Tappet
Pushrod
Pushrodcover&Rubberseal
40-1,-2,-3
Rockerarm
Rockerarmscrew&nut
41-1,-2
No.
43
44
45
46
47
48
49
69
74
75
80
82-1
83-1
90
91
93
95
110
120
149
152
153
Qty
2
1
1
1set
2ea.
2
2
1
1
1set
2
1set
1set
1set
1set
1
1set
1
1
1
1
1set
Item
Rockerarmpin
Rockerarmbracket(left)
Rockerarmbracket(right)
Valveset(In&Ex)
46-1,-2
Valvespring&Keeper&Retainer
47-1,-2,48
Valveretainer
Rockerarmcover
Intakemanifold(Intakepipe)
Muffler
Mufflermanifoldset
75-1,80
Mufflernut
Carburetorcomplete
Carburetorbodyassembly
82-1-1,-1-2,-1-3,-1-4,-1-5,-1-13
Carburetorscrew&springset
82-1-9,-1-10,-1-11,-1-12
Carburetorgasketset
82-1-6,-1-7,-1-8
Intakevelocitystack(airfunnel)
Enginemountset
95-1,-2,-3,-4,-5
Antilooseningnut
Sparkplug(CM-6)
Oilslinger
Screwpin(Fordriveflangesetting)
Electronicignitionsystem
153-1,-2,-3,-4,-5
153
153ー1
153ー4
153ー3
153ー2

Other manuals for FG-40

1

Other Saito Engine manuals

Saito FG-11 User manual

Saito

Saito FG-11 User manual

Saito FA-90R3 User manual

Saito

Saito FA-90R3 User manual

Saito FG-73R5 User manual

Saito

Saito FG-73R5 User manual

Saito FG-90R3 User manual

Saito

Saito FG-90R3 User manual

Saito FG-60R3 User manual

Saito

Saito FG-60R3 User manual

Saito FA-30S Golden Knight User manual

Saito

Saito FA-30S Golden Knight User manual

Saito FA-62B User manual

Saito

Saito FA-62B User manual

Saito FG-14B & FG-20 Operation manual

Saito

Saito FG-14B & FG-20 Operation manual

Saito FA-72B User manual

Saito

Saito FA-72B User manual

Saito FA-56B User manual

Saito

Saito FA-56B User manual

Saito FA-170R3-D User manual

Saito

Saito FA-170R3-D User manual

Saito FA-30S(H) User manual

Saito

Saito FA-30S(H) User manual

Saito FG-57TS User manual

Saito

Saito FG-57TS User manual

Saito FG-60R3 User manual

Saito

Saito FG-60R3 User manual

Saito FA-100Ti User manual

Saito

Saito FA-100Ti User manual

Saito FG-57T User manual

Saito

Saito FG-57T User manual

Saito FA-30S(H) User manual

Saito

Saito FA-30S(H) User manual

Saito FG-61TS User manual

Saito

Saito FG-61TS User manual

Saito FA-170R3 User manual

Saito

Saito FA-170R3 User manual

Saito FG-73R5 User manual

Saito

Saito FG-73R5 User manual

Saito FG-73R5 User manual

Saito

Saito FG-73R5 User manual

Saito FG-40 User manual

Saito

Saito FG-40 User manual

Saito FG-100TS User manual

Saito

Saito FG-100TS User manual

Saito FA-60T User manual

Saito

Saito FA-60T User manual

Popular Engine manuals by other brands

EBARA 4OY series Operating and maintenance manual

EBARA

EBARA 4OY series Operating and maintenance manual

Parker Torqmotor TC Series Service Procedure

Parker

Parker Torqmotor TC Series Service Procedure

Briggs & Stratton Quantum 625 Series Operator's manual

Briggs & Stratton

Briggs & Stratton Quantum 625 Series Operator's manual

Omron SMARTSTEP SERVO MOTORS System configuration

Omron

Omron SMARTSTEP SERVO MOTORS System configuration

Volkswagen Taro 1989 Workshop manual

Volkswagen

Volkswagen Taro 1989 Workshop manual

Hoyer HMA4 manual

Hoyer

Hoyer HMA4 manual

Simu SIMUBOX 80/25 Translation of the original manual

Simu

Simu SIMUBOX 80/25 Translation of the original manual

Siemens SIMOTICS XP 1MB155 operating instructions

Siemens

Siemens SIMOTICS XP 1MB155 operating instructions

Smitec ICOS 3110 Installation, use and maintenance manual

Smitec

Smitec ICOS 3110 Installation, use and maintenance manual

Kohler KD425-2 Use and maintenance

Kohler

Kohler KD425-2 Use and maintenance

ZIEHL-ABEGG ECblue Series quick start guide

ZIEHL-ABEGG

ZIEHL-ABEGG ECblue Series quick start guide

Graco 215-255 Instructions-parts list

Graco

Graco 215-255 Instructions-parts list

Tecumseh HMSK90 Operator's manual

Tecumseh

Tecumseh HMSK90 Operator's manual

Hiwin SSA user manual

Hiwin

Hiwin SSA user manual

SOMFY sonesse 30 rts Programming instructions

SOMFY

SOMFY sonesse 30 rts Programming instructions

MTD 350 Series Service manual

MTD

MTD 350 Series Service manual

Mitsubishi Electric Super Helicross Series instruction manual

Mitsubishi Electric

Mitsubishi Electric Super Helicross Series instruction manual

Leroy-Somer E27 Series Installation & maintenance

Leroy-Somer

Leroy-Somer E27 Series Installation & maintenance

manuals.online logo
manuals.online logoBrands
  • About & Mission
  • Contact us
  • Privacy Policy
  • Terms and Conditions

Copyright 2025 Manuals.Online. All Rights Reserved.