O.S. engine MAX-91SZ-Hring, Owner'S Instruction Manual

Page 1: ...ol equipment etc are accessible for checking at the same time 1 CONTENTS SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O S ENGINE NOTES ON INSTALLING COOLING FAN AND CLUTCH NOTES WHEN APPLYING AN ELECTRIC STARTER NOTES ON HEATING THE GLOW PLUG INTRODUCTION BEFORE STARTING ENGINE PARTS NAME INSTALLATION OF THE STANDARD ACCESSORIES INSTALLATION OF THE ENGINE FACTS ABOUT GLOWPLUGS CARBURETOR CONTROLS S...

Page 2: ... many other possibilities generally less obvious sources of danger but which under certain circumstances may also cause damage or injury 3 WARNINGS Never touch or allow any object to come into contact with the rotating parts Model engine fuel is poison ous Do not allow it to come into contact with the eyes or mouth Always store it in a clearly marked container and out of the reach of children Mode...

Page 3: ...r head down securely Take care that the glow plug clip or battery leads do not come into contact with rotating parts Adjust the throttle linkage so that the engine stops when the throttle stick and trim lever on the transmitter are fully retarded Alternatively the engine may be stopped by cutting off the fuel supply Never try to stop the engine physically 5 NOTES Take care that loose clothing ties...

Page 4: ...t clamp so that its grooved portion surrounds the crankpin and lower end of the connecting rod and securely tighten the fan or clutch onto the crankshaft Insert this groove onto the connecting rod BDC position Rotate the crankshaft so that the connecting rod comes to this position 7 NOTES WHEN APPLYING AN ELECTRIC STARTER Because of this initial tightness a standard electric starter may have diffi...

Page 5: ...X H RING WC making them interchangeable However higher gear ratio is required for the MAX 91SZ H RING which generates maximum power at lower rpm than the 61 size engines New design 60M C carburetor has three adjustable controls which enables independent adjustment at idling hovering and high speed INTRODUCTION Standard accessories Glow Plug No 8 Woodruff Key Needle Adjusting Screw M2 6x5 2pcs Inst...

Page 6: ...ble synthetic oil or a blend of both provided that they are always of top quality For consistent performance and long engine life it is essential to use fuel containing AT LEAST 18 lubricant by volume Some fuels containing coloring additives tend to deterriorate and may adversely affect running qualities If in doubt compare to a fuel known to be good Modelenginefuelispoisonous Donotallow it to com...

Page 7: ...cessed glowplug the O S Long Socket Wrench incorporates a special grip End Wrenches 8mm 13mm 14mm etc Needle Nose Pliers Long Socket Wrench With Plug Grip 13 ENGINE PARTS NAME Heatsink Head Carburetor Typr 60M C Crankshaft Propeller nut Crankcase Glowplug Beam Mount Cover Plate High Speed Needle Valve Fuel Inlet Mixture Control Valve Throttle Lever Idle Mixture Control Screw Mixture Control Valve ...

Page 8: ...ink head making sure that it is not cross threaded before tightening firmly Glow plug Washer The knurled heads of the two needle valves High Speed and Medium Speed are provided with diagonal slots for use with a screwdriver Alternatively formore positive location via an Allen hexagonal key these heads also have M2 6 internal threads intowhichM2 6x5mmAllencap headscrew may be installed To avoid ris...

Page 9: ...urce When the battery is disconnected the heat retained within the combustion chamber remains sufficient to keep the plug filament glowing thereby continuing to keep the engine running Ignition timing is automatic under reduced load allowing higher rpm the plug becomes hotter and appropriately fires the fuel air charge earlier conversely at reduced rpm the plug become cooler and ignition is retard...

Page 10: ...rew As the idle mixture control screw is installed with LOCTITE it may initialy feel stiff and it is suggested to use a littli oversized screwdriver The screw can be turned only 90 degrees either way Do not force to turn further or it may break or cause trouble NOTE 90 degrees 90 degrees 19 BASIC POSITION OF MIXTURE CONTROL SCREW Mixture Control Valve Thick Mixture Control Valve MIxture Control Sc...

Page 11: ...ngine over using the starter until the fuel is seen to reach carburetor In case the engine does not stop Hold the rotor head and pinch the fuel line to stop the fuel supply If it still does not stop pull off the fuel line from the carburetor It is necessary to readjust the throttle linkage so that the carburetor rotor is fully closed when the throttle stick and throttle trim on the transmitter are...

Page 12: ...ct for a fuel containing 20 lubricant and 15 30 nitromethane Bear in mind that fuels containing relatively large percentages of power boosting nitromethane operate at richer mixture settings than are needed for mild fuels and will therefore require the High Speed Needle Valve to be readjusted accordingly The type and percentage of lubricant used is also a factor here as noted later in these instru...

Page 13: ...oo far open Needle Valve too far closed High Speed Needle Valve Setting varies according to the curve When satisfactory hovering flight has been achieved land the modeI again and re check the engine s idle qualities 25 Now re check hovering performance It may be found that with the High Speed Needle Valve now set for optimum full throttle performance hovering will reveal symptoms of slightly lean ...

Page 14: ...r mostly accumulate here SUBSEQUENT READJUSTMENTS Once the engine has been run in and the carburetor controls properly set up it should be unnecessary to alter the mixture settings except to make minor changes to the Main High Speed Needle Valve occasionally to take account of differences in climatic condisitions However as previously mentioned the use of a different fuel particularly one containi...

Page 15: ...wise Land the model Idle for approx 10 seconds then reopen throttle to observe transition Float the model Idling OK Lean mixture Rich mixture High Speed Flight Lean mixture Rich mixture High Speed Flight OK Fine tuning of hovering mixture Open the Medium Speed Needle Valve Hovering OK Adjustment completed Open the High Speed Needle Valve Turn counter clockwise Close the High Speed Needle Valve Tur...

Page 16: ...mmended that a good in line filter be installed between the tank and carburetor 1 Finally injectsomeafter runoilintotheengine Rotate the engine a few times by hand to make sure that it is free and then with an electric starter for 4 to 5 seconds to distribute the oil to all the working parts These procedures will reduce the risk of starting difficulties and of internal corrosion after a period of ...

Page 17: ...ecessary Incorrect carburetor settings Return the needle valve and mixture control valve to basic position Incorrect servo linkage Re linkage after setting servo at neutral Reverse rotating direction of electric starter Mare sure it rotates counter clockwise seen from crankshaft side 31 Symptom Cause Corrective action Engine fires intermittently but does not run Insufficient fuel in the tank Fill ...

Page 18: ...nected or disconnected Check the connections and secure them Fuel tubing from tank to is split or broken Replace the tubing 33 Symptom Cause Corrective action Symptom Cause Corrective action Poor response Deteriorated glowplug Replace glowplug Incorrect carburetor settings Readjust low r p m range with metering needle and mixture control valve Poor r p m drop Too much throttle opening at idle Lowe...

Page 19: ...Pin Piston Pin Retainer 2pcs Connecting Rod Carburetor Complete 60M C Propeller Nut Thrust Washer Crankshaft Ball Bearing Front Carburetor Retainer Assembly Crankcase Crankshaft Ball Bearing Rear Crankshaft Gasket Set Cover Plate Glow Plug No 8 Woodruff Key Needle Adjusting Screw Head Gasket 0 1mm 0 2mm No Description 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Code No 29064000 29063100 29503400 290...

Page 20: ... 2pcs Carburetor Body Mixture Control Valve Assembly Carburetor Rotor Throttle Lever Retaining Screw 2pcs Throttle Lever Assembly Mixture Control Screw Mixture Control Valve Stopper Needle Valve Holder Assembly O Ring L 2pcs O Ring S 2pcs O Ring 2pcs Needle Valve Holder 9 9 1 9 2 9 3 9 4 10 Carburetor Rubber Gasket Needle Needle Valve Assembly O Ring 2pcs Needle Valve Holder Assembly Ratchet Sprin...

Page 21: ...ovement without notice GLOWPLUG DRIVE HUB ASSEMBLY w woodruff key Drive Hub Woodruff Key CRANKSHAFT CLAMP M3x12 CAP SCREW SET 10pcs 79871140 79871150 For 91SZ H M3x15 39 THREE VIEW DRAWING Displacement Bore Stroke Practical R P M Power output Weight SPECIFICATIONS Dimensions mm 14 95 cc 0 912 cu in 27 7mm 1 091 in 24 8mm 0 976 in 2 000 16 000 r p m 3 3 ps 15 000 r p m 605g 21 36oz JAPAN JAPAN JAPA...

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