Throttle & Choke Control Installation & Adjustment Guide
Throttle &Choke ControlInstallation &Adjustment GuideContentsPage No.Safety Precautions . 2-3Magnum Twin Horizontal Shaft . 4-7Magnum Twin Vertical Shaft . 8-10Command Single Cylinder . 11-15Command Twin Cylinder . 16-19OHC Twin Cylinder . 20-231
Safety PrecautionsTo insure safe operations please read the following statements and understand their meaning. Also refer to yourequipment owner's manual for other important safety information. This manual contains safety precautionswhich are explained below. Please read carefully.WARNINGWarning is used to indicate the presence of a hazard that can cause severe personal injury, death, or substantialproperty damage if the warning is ignored.CAUTIONCaution is used to indicate the presence of a hazard that will or can cause minor personal injury or propertydamage if the warning is ignored.NOTENote is used to notify people of installation, operation, or maintenance information that is important but nothazard-related.For Your Safety!These precautions should be followed at all times. Failure to follow these precautions could result in injury toyourself and others.WARNINGWARNINGWARNINGCarbon Monoxide can causesevere nausea, fainting or death.Accidental Starts can causesevere injury or death.Explosive Gas can cause fires andsevere acid burns.Do not operate engine in closed orconfined area.Disconnect and ground spark pluglead before servicing.Charge battery only in a wellventilated area. Keep sources ofignition away.Lethal Exhaust Gases!Engine exhaust gases containpoisonous carbon monoxide.Carbon monoxide is odorless,colorless, and can cause death ifinhaled. Avoid inhaling exhaustfumes, and never run the engine ina closed building or confined area.CAUTIONElectrical Shock can cause injury.Do not touch wires while engine isrunning.Electrical Shock!Never touch electrical wires orcomponents while the engine isrunning. They can be sources ofelectrical shock.2Accidental Starts!Disabling engine. Accidentalstarting can cause severe injuryor death. Before working on theengine or equipment, disable theengine as follows: 1) Disconnectthe spark plug lead(s). 2) Removebattery cables (remove negative (-)lead first). Reconnect negative (-)lead last when reconnecting battery.Explosive Gas!Batteries produce explosivehydrogen gas while being charged.To prevent a fire or explosion,charge batteries only in wellventilated areas. Keep sparks, openflames, and other sources ofignition away from the battery at alltimes. Keep batteries out of thereach of children. Remove alljewelry when servicing batteries.Before disconnecting the negative(–) ground cable, make sure allswitches are OFF. If ON, a sparkwill occur at the ground cableterminal which could cause anexplosion if hydrogen gas orgasoline vapors are present.
Safety PrecautionsWARNINGHot Parts can cause severe burns.Do not touch engine while operatingor just after stopping.Hot Parts!Engine components can getextremely hot from operation. Toprevent severe burns, do not touchthese areas while the engine isrunning–or immediately after it isturned off. Never operate theengine with heat shields or guardsremoved.WARNINGWARNINGRotating Parts can cause severeinjury.Explosive Fuel can cause fires andsevere burns.Stay away while engine is inoperation.Stop engine before filling fuel tank.Rotating Parts!Keep hands, feet, hair, and clothingaway from all moving parts toprevent injury. Never operate theengine with covers, shrouds, orguards removed.Explosive Fuel!Gasoline is extremely flammableand its vapors can explode ifignited. Store gasoline only inapproved containers, in wellventilated, unoccupied buildings,away from sparks or flames. Do notfill the fuel tank while the engine ishot or running, since spilled fuelcould ignite if it comes in contactwith hot parts or sparks fromignition. Do not start the enginenear spilled fuel. Never usegasoline as a cleaning agent.3
Magnum Twin HorizontalMagnum Twin Cylinder Horizontal Shaft EnginesHow to Install Dual Controls And Make AdjustmentsPage No.A. Throttle Control . 5-6B. Choke Control . 6C. Starting the Engine . 6D. Changing the High Idle RPM . 71. Increase2. DecreaseE. Changing a Constant RPM Control . 7F. Setting the Low Idle RPM . 7G. Carburetor Fuel Mixture . 7H. Shutting the Engine Down . 7Tools Needed1/4" wrench, or nut driver3/8" - 7/16" wrench, or ratchet and socketBlade type screwdriverTorque wrench is requiredTachometer4
Magnum Twin HorizontalEngine Throttle Control Lever(Shown in Low Idle Position)Throttle Control WireThrottle Cable(Under CableClamp)Constant Speed Control(When RemoteCable is Not Used)GovernorSpringHigh Idle RPMStop BracketOptional Throttle CableBracket LocationHigh Idle RPMStop Bracket ScrewFigure 1. Magnum Twin Horizontal Throttle Control.A. Throttle Control (Does not apply to customersupplied control plate.)1. Engines with the square air cleanerassembly- Remove the two wing nuts (top ofair cleaner cover), the cover, and the tworubber seals, and then lift the element and dishout.Disconnect the breather hose from the aircleaner base by pushing downward.Remove the air cleaner base 3/8" hex. head.retaining screw, air cleaner base, and ovalair tube.2. Engines with dome style air cleaner startwith #3.3. Loosen the throttle control cable clamp locatedon top of the intake manifold, or on the intakemanifold bracket, located to the right on one ofthe manifold mounting bolts.4. Position the application throttle control in thefast throttle position. Then move the throttlecontrol back 3/16" (4.75 mm). Insert the controlcable bowden wire in the proper hole of theengine control lever, which is located onthe side of the carburetor air intake elbow.Leave the air cleaner base gasket on thecarburetor air cleaner elbow.5
Magnum Twin Horizontal5. Grasp the control cable and place it under thecable clamp. Pull until the cable is taut, thentighten the clamp screw. NOTE: The enginecontrol lever should be against the high idleRPM stop bracket.6. Move the application throttle control to theslow position, then to fast. Check the enginecontrol to assure it stops against the high idleRPM stop bracket.NOTE: When the application throttle controllever is in the slow position theengine governor spring must be freeof tension or pushing pressure. A nonfree spring can affect the RPM.NOTE: Do not move the governor spring toother holes without approval.B. Choke Control (See Figure 2)1. Loosen the cable clamp screw on the bottomfront side of the intake manifold for a forwardpull choke, or on the air intake elbow for areverse pull.3. Position the choke control so it bottoms,then pull it back approximately 1/16" (1.5 mm).Make sure that the carburetor choke is fullyopened before tightening cable clamp.4. Reassemble all air cleaner components andthe crankcase breather tube.C. Starting the Engine1. Position the application throttle control tomid/full throttle.2. Place the choke control into the on position.3. Turn the key switch or push the start button.Release as soon as the engine starts.4. Push the choke control inward. If the enginehesitates, pull the choke control out until theengine regains its momentum, then push thechoke control in again. Repeat as required.5. Set the throttle control to the desired RPM.2. Place the choke control cable under the intakemanifold from the front of engine (front pullchoke). Insert the cable bowden wire into thechoke control (front or reverse pull). Thenplace choke cable under the cable clamp.Reverse Pull Choke ControlFront PullChoke ControlAir IntakeElbowChoke Control Lever(Shown In Open Position)Figure 2. Magnum Twin Horizontal Choke Control.6
Magnum Twin HorizontalD. Changing the High Idle RPMTo Increase the High Idle RPM1. With the engine running, loosen the throttlecable clamp screw enough to slide the cable.2. Loosen the engine high idle stop bracket screw1/2 to 3/4 turn. (See Figure 1 on page 4.)3. Position the application throttle control to fastthen back it off approximately 3/16" (4.75 mm).4. Pull the throttle control cable until the requiredRPM is obtained. (NOTE: Tap the high RPMstop bracket to the left if it does not movewhen the cable is pulled.) Tighten both highRPM stop screw and the cable clamp screw.5. Move the application throttle control to slow,then to fast. Check the RPM with atachometer.To Decrease the High Idle RPMRefer to the above steps 1, 2, and 3.4. Push the throttle control cable until therequired high idle RPM is obtained.5. Tighten the cable clamp screw.6. Slide or tap the high idle stop to the right untilit is against the engine control lever. Torquethe high RPM stop bracket screw to 70 in. lbs.7. Move the application throttle lever to slow,then to fast. Check the RPM with atachometer.E. Changing the Constant RPM Control Engine1. With the engine running, loosen two nuts onthe RPM adjusting rod location on top of theintake manifold. The rod is connected to thegovernor spring (not shown on Figure 1).2. To increase the RPM: Hold the adjusting rodand turn one nut inward until the required RPMis obtained.a. Turn the second nut against the first nut.Use two wrenches to lock the nutstogether. Check the RPM.3. To decrease the RPM: Turn the two nutsoutward until the required RPM is obtained.Refer to Step 2a for a final adjustment.F. Setting the Low Idle RPM1. The low idle RPM can be increased ordecreased by turning the low idle stop screw(located near the top of the carburetor andbelow the throttle lever with the link attached)inward to increase, or outward to decrease.G. Carburetor Fuel Mixture(Fixed & adjustable jet carburetors)1. The fuel mixture should not require adjustmentunless the RPM has significantly changed andthe engine has been running for more than fiveminutes.H. Shutting the Engine Down1. Position the application throttle lever in theslow position when not required to run engineout of fuel. Allow the engine to come to lowidle.2. Turn the key switch off, or push and hold thestop button until the engine stops.3. When required to run the engine out of fuel,leave the throttle control in the fast positionand run until the engine stops.4. Turn the key switch off.5. A constant speed unit is normally controlledthrough a low idle pull-down device which isautomatically activated when the load isremoved. Before stopping remove load, letengine decelerate, then turn key or switch tooff position.7
Magnum Twin VerticalMagnum Twin Cylinder Vertical Shaft EnginesHow to Install Dual Controls and Make AdjustmentsPage No.A. Throttle Control . 91. Right Side Pull2. Left Side PullB. Choke Control . 9-10C. Starting the Engine . 10D. Changing the High Idle RPM . 10E. Setting the Low Idle RPM . 10F.Carburetor Fuel Mixture . 10G. Shutting the Engine Down. 10Tools Needed1/4" wrench or nut driver5/6" - 3/8" wrench, ratchet and socket, or nut driverBlade type screwdriverTachometer8
Magnum Twin VerticalHigh Idle AdjustingScrew with Lock NutChoke CableScrew and ClampThrottle CableScrew and ClampLeft SideThrottle PullRight SideThrottle PullThrottleControl LeverThrottle CableScrew and ClampFigure 1. Magnum Twin Vertical Throttle and Choke Controls.A. Throttle Control1. Loosen the throttle control (right side or leftside pull cable clamp screw.2. Position the application throttle control in thefast position, then move the throttle controlback 3/16" (4.75 mm). Insert the control cablebowden wire into the proper hole or swivelclamp in the engine control lever which islocated on the left side of the intake manifoldfor a left side pull. For a right side pull, loosenthe control cable clamp screw located on theright side of the intake manifold.3. Position the control cable under the cableclamp and grasp the cable pull until it is tautthen tighten the cable clamp screw.NOTE: The engine throttle control should beagainst the high idle adjusting screw.4. Move the application throttle control to theslow position then to the fast position. Checkthe engine control lever to assure it stopsagainst the high idle adjusting screw.B. Choke Control (See Figure 1)1. Loosen the choke control cable clamp screwon the air cleaner intake elbow.2. Insert the choke cable bowden wire into thechoke lever on the carburetor, then place thecable under the cable clamp.3. Push the application choke control in untilit bottoms.4. Grasp the cable near the cable clamp on theengine, push lightly until the application chokecontrol moves approximately 1/16" (1.5 mm)from its bottomed position, hold the cable andtighten the clamp screw.9
Magnum Twin Vertical5. Check choke function by pulling the chokecontrol outward until it stops.NOTE: Make sure that the carburetor chokecontrol does not stop against thechoke cable, because it will preventfull choking and engine starting.6. Push the choke control in until it bottoms,release it. The choke control should moveoutward slightly upon release which means it isproperly set.C. Starting the Engine1. Position the application throttle control tomid or fast throttle.2. Place the choke control into the on position.3. Turn key switch or push start button, release assoon as the engine starts.4. Push the choke control inward. If the enginehesitates, pull the choke control out until theengine regains its momentum, then push thechoke control in again.) Repeat as required.5. Set the throttle control to the desired RPM.D. Changing the High Idle RPM1. Loosen the high idle adjusting screw lock nutlocated on the intake manifold left side.2. Loosen the throttle control cable clamp screwto allow the cable slide.3. With the engine running, move the applicationthrottle control to fast then back it off 3/16"(4.75 mm).4. Grasp the cable near the engine cable clamp,pull until the engine throttle lever stops againstthe high idle adjusting screw.105. To increase the high idle RPM, turn the stopscrew outward while pulling on the cable untilthe desired RPM is obtained.6. Tighten the high idle screw lock nut and thecable clamp screw.7. To decrease the high idle RPM, follow steps1, 2, 3, and 4 then turn the screw inward, untilthe desired RPM is obtained. Proceed to step 6.8. To check the RPM change, move theapplication throttle lever to slow, then to fast.Check the RPM with a tachometer.E. Setting the Low Idle RPM1. Position the application throttle control in thelow/slow position.2. The low idle RPM can be increased/decreasedby turning the low idle stop screw (located nearthe top center of the carburetor) inward toincrease, outward to decrease.F. Carburetor Fuel Mixture1. The fuel mixture should not require adjustmentunless the RPM has significantly changed, andthe engine has been running for more than fiveminutes.G. Shutting the Engine Down1. Position the application throttle lever in theslow position when not required to run theengine out of fuel. When required to run theengine out of fuel, leave the throttle in the fastposition until the engine stops.2. Turn the key switch off, or push and hold thestop button in until the engine stops.
Command Single CylinderCommand CV & CH Single Cylinder ModelsControl Installation InstructionsPage No.A. How to Install the Single Throttle and Choke control cable . 12B. Engines Equipped with an Optional Kill Switch - (Single Control) . 12C. Starting the Engine with Single Control cable . 12D. How to Install Dual Control Cables . 131. Throttle Control2. Choke ControlE. Starting an Engine Equipped with Dual Control Cables . 14F. Changing the High Idle RPM on a CV Engine with Single Control Engine . 14G. Changing the high idle RPM on a CH Engine with Variable and Constant RPM Control . 14H. Changing the high idle RPM on a CV Engine with Dual Controls . 151. Increase RPM2. Decrease RPMI.Setting the Low Idle RPM . 15J.Fuel Mixture . 15Tools Needed8 and 10 mm wrench, ratchet and socket, or nut driverBlade type screwdriverTachometerTorque wrench as required11
Command Single CylinderChoke LinkClampControl CableHigh Idle RPMAdjusting Screws(At Slots 1 and 2)Control Alignment HolesChoke Adjusting ScrewControl Plate LeverKill Switch Adjusting ScrewControl PlateKill SwitchFigure 1. Single Cable Control.A. How To Install the Single Throttle and ChokeControl Cable (See Figure 1)1. Loosen cable clamp screw on engine controlplate.2. Position application throttle control lever in thefast throttle position. (Single control cable)Insert the cable bowden wire into the enginecontrol plate lever.3. Position the cable under the control plate cableclamp.B. Engines Equipped With An Optional KillSwitch - Single Control (See Figure 1)1. Position application throttle control in the stopposition. If the engine continues to run, turn thekill switch adjustment screw inward until theengine stops. Then turn the screw anadditional 1/2 - 3/4 turn to assure it willfunction properly.C. Starting The Engine With Single Control Cable1. Place the throttle/choke control into the chokeposition.2. Start the engine.4. Pull cable upward until the control plate leveralignment hole is in line with the control platehole.3. As soon as the engine starts, move thethrottle/choke control to fast position ordesired RPM.5. Tighten control cable clamp screw.4. If the engine stops, repeat steps 1
equipment owner's manual for other important safety information. This manual contains safety precautions which are explained below. Please read carefully. WARNING Warning is used to indicate the presence of a hazard that can cause severe personal injury, death, or substantial property damage if the warning is ignored. CAUTION
must pass. Choke inserts are available in a complete range of sizes, generally identified by choke diameter stated in 64ths of an inch; for example, a "32 bean" is equivalent to a /2-in. choke diameter. The adjustable choke typically does not allow an accurate choke size due to the complex geometry of the flow around the choke bean.
Important: If your gun is equipped with choke tubes, do not use a brass brush to clean the barrels without having a choke tube installed. Barrels that utilize choke tubes must also have the choke tubes removed to clean and oil the threads inside the barrel and the choke tubes themselves. This will protect the threads and prevent dirt build
Adjustable Choke Valve 1502 Stem Nut Washer Hand Wheel Indicator Lock Screw Choke Stem Outsider O-ring Seal Piston Inside O-ring Stem Seal Snap Ring Bonnet Bolt Thumb Screw Bonnet Extension Choke Bonnet Bonnet O-ring Bonnet Back Up Ring Wing Nut Lip Seal Choke Seat Choke Body Plug Stem Stem Cap Retainer Ring Segment Grease Fitting Lock Plug Ass .
set to type 3. For 3-wire throttle pots or EZ Go with ITS converter box, set to Type 2. The default is Type 2. Throttle: This allows the Throttle range to be calibrated. Cycle the program options to “Throttle” on the Dash Display, select Street Mode, press the Accelerator Pedal to the floor (Max Throttle).
All models except late 8N. 8N9596 Idle jet. Late 8N. 8N9622 Throttle shaft neoprene packing. 8N9689 Choke shaft felt packing. All models (1939-1964). 9N9695 Choke shaft felt retainer. All models (1939-1964). 9N9914 Economizer jet. For tractors 9N, 2N, 8N. REPLACES Choke & Throttle Parts
1-8@1.722 A A Manual Valve Cutback Plunger Kickdown Compensator Throttle Boost Throttle Body Throttle Valve T Throttle body No Vent here Check Valve P R N D2 D1 L D2 Starts in 2nd. Shifts to 3rd Kickdown to 2nd but not to 1st D1 Starts in 1st and shifts 1-2 & 2-3 Kickdown to 2nd or 1st, speed controlled L Starts in Low [1st] and does not shift.
wall respectively. The reduction is both dependent on pressure ratio and throttle plate angle. The effective area has showed to follow the same behaviour as the mass flow rate for the larger simulated throttle plate angle 31 , i.e. an increase as the pressure drop over the throttle plate becomes larger. At the smaller throttle plate angle 21 .
160F 168F-1 168F-2 170F 173F 177F 182F 188F 190F . 2. To start a cold engine, move the choke lever to the CLOSE position. To restart a warm engine, leave the choke lever in the OPEN position. Some engine applications use a remotely-mounted choke control rather than the engine-mounted choke lever shown here. .
