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LONG SOCKET WRENCH

Recommended for easy removal 
and replacement of the angled 
and recessed glowplug, the 
O.S.Long Socket Wrench 
incorporates a special grip.

SILICONE FUEL LINE

Heatproof silicone tubing of 
approx. 5mm o.d. and 2mm i.d. 
is required for the connection 
between the fuel tank and 
engine.

CARBURETOR CONTROLS

The Needle-Valve:

The Mixture Control Screw:

The Throttle Stop Screw:

For setting the minimum idling speed:

Four adjustable controls are provided on this 
carburettor. 

For adjusting the mixture strength when the throttle 
is fully open.

For adjusting the mixture strength at part-throttle 
and idling speeds, to obtain steady idling and 
smooth acceleration to mid speeds.

Needle Valve

Mixture Control Valve
Assembly Screw

Throttle Stop Screw

NOTE: Readjustment may be necessary, 
occasionally to allow for changes in fuel formula 
gear ratio or clutch engagement point.

The Metering Needle:

Metering Needle

For changing the feeling at mid speads and 
acceleration. (Do not rotate the screw more chan 
one turn.)

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Summary of Contents for MAX-21VZ-R

Page 1: ...ontained therein Also please study the entire contents of this instruction manual so as to familiarize yourself with the controls and other features of the engine Keep these instructions in a safe place so that you may readily refer to them whenever necessary It is suggested that any instructions supplied with the vehicle radio control equipment etc are accessible for checking at the same time ...

Page 2: ... request that these instructions are also passed on to its new owner SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O S ENGINE The advice which follows applies basically to ALL MODEL ENGINES and is grouped under two headings according to the degree of damage or danger which might arise through misuse or neglect WARNINGS NOTES These cover events which might involve serious in extreme circumstances eve...

Page 3: ...rces of sparks or anything else which might ignite it Do not smoke or allow anyone else to smoke near to it Never operate your engine in an en closed space Model engines like automobile engines exhaust deadly carbon monoxide Run your engine only in an open area Model engines generate considerable heat Do not touch any part of your engine until it has cooled Contact with the muffler silencer cylind...

Page 4: ...se of the more powerful highspeed engines may eventually impair your hearing and such noise is also likely to cause annoyance to others over a wide area The wearing of safety glasses is also strongly recommended Take care that the glowplug clip or battery leads do not come into contact with rotating parts Also check that the linkage to the throttle arm is secure For their safety keep all onlookers...

Page 5: ...the fuel supply by pinching the fuel delivery line from the tank Warning Immediately after a glowplug ignition engine has been run and is still warm conditions sometimes exist whereby it is just possible for the engine to abruptly restart if it is rotated over compression WITHOUT the glowplug battery being reconnected 5 ...

Page 6: ...ust Seal Ring Dust Cap 3 16 18 The MAX 21VZ R is high performance 3 5cc class power unit for one eighth scale radio controlled Track racing cars It has been de signed to meet the exacting requirements of the world s most expert drivers An exhaustive program of research development and proto type testing has resulted in one of the most powerful production model racing car engines currently availabl...

Page 7: ...s INSTALLATION OF THE CARBURETOR As delivered the engine has its carburetor lightly install into its intake boss Secure it as follows Loosen the retainer screw rotate the carburetor to its correct position and make sure that it is pressed well down into the intake boss compressing the rubber gasket before retightening screw 1 2 Rotate the retainer nut gently until it stops Tighten a further 120 18...

Page 8: ...not leave the battery connected while adjusting the needle With a glowplug engine ignition is initiated by the application of a 1 5 volt power source 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 th...

Page 9: ...come into contact with the eyes or mouth Always store it in a clearly marked container and out of the reach of children Model engine fuel is also highly flammable Keep it away from open flame excessive heat sources of sparks or anything else which might ignite it Do not smoke or allow anyone else to smoke near to it Please note that with high nitro fuels although power may be increased for competi...

Page 10: ...um idling speed Four adjustable controls are provided on this carburettor For adjusting the mixture strength when the throttle is fully open For adjusting the mixture strength at part throttle and idling speeds to obtain steady idling and smooth acceleration to mid speeds Needle Valve Mixture Control Valve Assembly Screw Throttle Stop Screw NOTE Readjustment may be necessary occasionally to allow ...

Page 11: ...fler pressurized fuel system Temporarily remove the glowplug to check that it glows bright red when energized Open the Needle Valve 3 turns from the fully closed position Switch on the transmitter and receiver and set the throttle very slightly opened from the idling position see sketch top right DO NOT energize glowplug but apply electric starter to draw fuel to carburetor Now connect glowplug ba...

Page 12: ...pply pinch the fuel delivery line to the carburetor Run the car on the track until one tank of fuel has been consumed then close the Needle Valve 30 and run the car for another full tank of fuel Repeat this procedure until 5 more tanks of fuel have been consumed during which time the throttle may be opened for brief bursts of increased power 30 30 3 0 Needle The position of the needle valve when s...

Page 13: ...el s speed Next return the car to the starting point close the Needle Valve 30 and repeat the run taking note of the improvement in performance Continue with further runs gradually reducing the Needle Valve setting and aiming to achieve the highest straight line speed Remember however that if the Needle Valve is shut down too far the engine will overheat and accompanied by visibly diminished exhau...

Page 14: ... the throttle opening to be reduced Finally beyond the nominal break in period a slight readjustment toward a leaner needle setting may be required to maintain performance With the engine running close the throttle and allow it to idle for about five seconds then reopen the throttle fully If at this point the engine puffs out an excessive amount of smoke and the vehicle does not accelerate smoothl...

Page 15: ...EALIGNMENT OF METERING NEEDLE AND MIXTURE CONTROL VALVE First rotate the Metering Needle until its slotted head is flush with the carburetor body This is the standard position In the course of making carburetor adjustments it is just possible that the Metering Needle and the Mixture Control Valve may be inadvertently screwed in or out too far and thereby moved beyond its effective adjustment range...

Page 16: ...on drain out any fuel that may remain in the fuel tank Afterwards energize the glow plug and try to restart the engine to burn off any fuel that may remain BEFORE STARTING THE ENGINE 1 2 Before starting the engine for the first run of the day remove the glowplug and check the engine by rotating the flywheel by hand It should rotate smoothly Now turn the engine with an electric starter until fuel i...

Page 17: ...to the engine and rotate the engine with an electric starter for 4 to 5 seconds to distribute the oil to all the working parts inside the engine Repeat this procedure until the engine fails to fire Do this while the engine is still warm Note 5 Do not inject after run oil into the carburetor as this may cause the O rings inside the carburetor to deteriorate These procedures will reduce the risks of...

Page 18: ...ENGINE EXPLODED VIEW Type of screw C Cap Screw M Oval Fillister Head Screw F Flat Head Screw N Round Head Screw S Set Screw 4 3 2 C M2 6X7 q 0 9 8 6 5 4 1 1 1 1 2 7 w e r C M3X16 C M2 6X18 18 ...

Page 19: ...omplete Type 20K Connecting Rod Piston Pin Retainer 2pcs Piston Pin Cylinder Piston Assembly Heatsink Head Assembly Description Code No Cover Plate e w q 0 9 8 7 6 5 4 3 2 1 23757000 22826140 71641700 23763000 23764000 23752000 23730010 23751000 23731000 23715000 23781000 23755000 23817000 23906000 23753000 23754600 No 1 1 1 2 r 23754620 23754610 23818190 23981700 Outer Head Inner Head Carburetor ...

Page 20: ...retor Rubber Gasket Ball Link No 3 Dust Cover Metering Needle Assembly Slide Valve Carburetor Body Fuel Inlet No 9 O Ring Needle Valve Assembly Throttle Stop Screw O Ring S 2pcs O Ring L 2pcs Mixture Control Valve Assembly Description Code No Needle Needle Holder Assembly 9 8 7 6 5 4 2 2 2 1 3 2 1 2 1 1 1 29015019 23781400 22884220 27881820 23781610 23781200 23781100 23818176 46066319 23618190 238...

Page 21: ...43 72106041 22826140 72106042 72106140 72106141 72106142 22826140 72106050 72412000 72412100 72412200 71641700 SUPER AIR CLEANER 202 202 Cleaner Body 202 Filter Elements T 2040 TUNED SILENCER ASSEMBLY T 2040 Tuned Silencer Body Pressure Nipple Exhaust Seal Ring Joint Spring T 2040 EXHAUST HEADER PIPE ASSEMBLY Exhaust Header Pipe Header Pipe Spring Exhaust Seal Ring T 2040 TUNED SILENCER COMPLETE S...

Page 22: ... output Weight SPECIFICATIONS THREE VIEW DRAWING JAPAN 20K 21 37 4 φ3 3 30 8 45 83 7 29 6 43 9 21 27 5 15 3 99 UNF 28 1 4 49 6 3 46 cc 0 211cu in 16 6 mm 0 654in 16 0 mm 0 630in 3 000 42 000 r p m 2 5 bhp 34 000 r p m 315 5g 11 14oz Dimensions mm 22 ...

Page 23: ...eserved Printed in Japan 120100 TEL 06 6702 0225 FAX 06 6704 2722 6 15 3 Chome Imagawa Higashisumiyoshi ku Osaka 546 0003 Japan U N E Q U A LLED QUALITY PRECISION PERFOR M A N C E E S T A BLISHING THE STANDARDS OF EXCELLE N C E URL http www os engines co jp ...

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