It is of vital importance, before attempting to operate your engine, to read the general 'SAFETY INSTRUCTIONS AND WARNINGS' section on pages 2-5 of this booklet and to strictly adhere to the advice contained 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.
CONTENTS SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE 2~ 5 CARBURETOR CLEANLINESS 17~18 18~19 INTRODUCTION, BASIC ENGINE PARTS 6 BEFORE STARTING THE ENGINE CARE AND MAINTENANCE INSTALLATION 7 GUARANTEE 20 AIR CLEANER 8~11 THREE VIEW DRAWING 21 GLOWPLUG 11~12 EXPLODED VIEW 22 TOOLS, ACCESSORIES, etc. 12~13 ENGINE PARTS LIST 23 CARBURETOR EXPLODED VIEW & PARTS LIST 24 O.S.
SAFETY INSTRUCTIONS AND WARNINGS ABOUT YOUR O.S. ENGINE Remember that your engine is not a "toy", but a highly efficient internalcombustion machine whose power is capable of harming you, or others, if it is misused. As owner, you, alone, are responsible for the safe operation of your engine, so act with discretion and care at all times. If at some future date, your O.S. engine is acquired by another person, we would respectfully request that these instructions are also passed on to its new owner.
WARNINGS • Never operate your engine in an enclosed space. Model engines, like automobile engines, exhaust deadly carbon-monoxide. Run your engine only in an open area. • Model engine fuel is poisonous. 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. • Model engines generate considerable heat. Do not touch any part of your engine until it has cooled.
NOTES • This engine is intended for model cars. Do not attempt to use it for any other purpose. • The wearing of safety glasses is also strongly recommended. • Mount the engine in your model securely, following the manufacturers' recommendations, using appropriate screws and locknuts. • 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. • Fit an effective silencer (muffler).
NOTES • To stop the engine, fully retard the throttle stick and trim lever on the trans-mitter, or, in an emergency, cut off the fuel supply by pinching the fuel delivery line from the tank. • Warning! Immediately after a glowplugignition 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.
The MAX-21RZ-V01b and MAX-21RZ-V01b(P) are high performance 3.5cc class power units for oneeighth-scale radio-controlled 'off-road' or 'buggy' cars. They have been designed to meet the exacting requirements of the world's most expert drivers. An exhaustive program of research, development and prototype testing has resulted in one of the most powerful production model racing car engines currently available.
INSTALLING THE GLOWPLUG Fit washer to glowplug and insert carefully into heatsink head, making sure that it is not cross-threaded before tightening firmly. Chassis Chamfer inside edges of bearers. Glow plug Washer INSTALLATION OF THE CARBURETOR As delivered, the engine has its carburetor lightly fit into its intake boss. Secure it as follows. 1.
AIR CLEANER TYPE 201 This is a heavy-duty wet type air cleaner that has been developed specifically for 3.5cc 'off-road' model car engines. It contains a specially impregnated filter element which more positively prevents highly damaging dust and dirt from being drawn through the carburettor, yet allows engine performance to be maintained for longer periods between element renewals. It is more compact than the standard O.S. HD Air Cleaner and this makes it easier to install within a car body.
If your fingers become contaminated, wash them with soap and water. ASSEMBLY 1. Slide the element base over the center tube (See Fig.1) and press down. If it is tight at the bottom, apply one or two drops of fuel at the point marked in Fig.2 NOTE: During storage, the oil may have become unevenly dispersed through the element. This will be indicated if the blue color of the element material appears patchy.
INSTALLATION 1.Apply instant setting glue to the joint between the air cleaner and the intake elbow and secure with strap supplied. ¡ Apply instant fixing glue. Washer Assembly Do not apply Screw glue to carburettor Strut 2. Fit the other end of the elbow over the carburettor intake and secure with strap supplied. Do not use glue at this point. 3. It is advisable to brace the outer end of the air cleaner to the car chassis with a piano wire strut.
FURTHER PRECAUTIONS The role of the glowplug When removing the air cleaner, check the inside of the center tube and carburetor venturi. If any dirt is detected, this indicates that the filter element was incorrectly installed or should have been replaced earlier.In this event, it is vitally important to wash out the inside of the engine thoroughly, with alcohol or fuel,before it is used again, otherwise rapid wear of the piston, cylinder,bearings, connecting-rod, etc., will occur.
When to replace the glowplug Please note that with high-nitro fuels, although power may be increased for competition purposes, glowplug elements do not last so long and engine life will be shortened. Apart from when actually burned out, a plug may need to be replaced because it no longer delivers its best performance, such as when: • Filament surface has roughened and turned white. • Filament coil has become distorted.
BATTERY LEADS CARBURETOR CONTROLS These are used to conduct current from the battery to the glowplug. For convenience, special leads with a suitable clip to fit the glowplug terminal, are commercially available. Three adjustable controls are provided on this carburettor. The Needle-Valve: For adjusting the mixture strength when the throttle is fully open. ¡ LONG SOCKET WRENCH Recommended for easy removal and replacement of the deeply recessed glowplug, the O.S.
STARTING THE ENGINE & RUNNING-IN ('Breaking-in') For long life and high performance, every engine needs to be 'run-in' or 'broken-in'. With care, runningin of the MAX-21RZ-V can be carried out with it installed in the vehicle. Be sure to fit the air-cleaner to the carburetor and to use a muffler-pressurized fuel system. • Now connect glowplug battery lead to heat the plug filament and start the engine. Needle Valve Close The following procedure is suitable for these engines when the O.S.
Attention: It is vitally important to set the throttle at the correct position before starting the engine. If the engine is allowed to run with the throttle too far open under ''no load'' conditions (i.e. with the driving wheels not in contact with the ground) it will rapidly over-heat and may be seriously damaged. may be opened for brief bursts of increased power. If the engine stops at medium speeds, close the Mixture Screw 45-90˚. Needle 30˚ The position of the needle-valve when starting the engine.
◆ Having established the optimum Needle-Valve setting, check the Mixture Control Valve setting as follows. IF THE ENGINE FAILS TO START Check the following: ◆ Glowplug battery discharged or glowplug defunct. ◆ Fuel not reaching carburetor. ◆ Engine flooded. Do not over-prime. (This could also cause hydraulic lock and damage the engine on application of the electric starter.) Remove glowplug, close needle-valve and apply starter to pump out surplus fuel.
Warning! Mixture adjustments (whether via the Mixture Control Valve, or the Needle-Valve) cannot be made accurately under 'no-load' conditions, which, in any case, are not advised, since such operation carries the risk of seriously damaging the engine through over-revving and overheating. CARBURETOR CLEANLINESS The correct functioning of the carburetor depends on its small fuel orifices remaining clear. (See Care and Maintenance section on Page19.
■ REALIGNMENT OF MIXTURE CONTROL VALVE BEFORE STARTING THE ENGINE In the course of making carburetor adjustments, it is just possible that the Mixture Control Valve may be inadvertently screwed in or out too far and thereby moved beyond its effective adjustment range.Its basic position can be found by first rotating the Mixture Control Valve until its slotted head is flush with the carburettor body. The valve is then screwed in exactly 1 turn to re-establish its neutral position. 1.
Warning! Do not attempt to turn the engine with the starter if the engine is over-primed (flooded) with fuel. To do so is likely to seriously damage the engine. inside the engine. Repeat this procedure until the engine fails to fire. Do this while the engine is still warm. 4. Then, inject some after-run oil into the engine, and rotate the engine with an electric starter for 4 to 5 seconds to distribute the oil to all the working parts. CARE AND MAINTENANCE 1.
GUARANTEE This engine is constructed from the very best materials available and to the very highest engineering standards, using the most advanced precision machinery. However, the extremely high stresses imposed by car racing operation under very severe conditions, stresses which are exacerbated by the use of powerful fuels containing very high concentrations of nitromethane, constitute hazards which are beyond a manufacturer's control.
THREE VIEW DRAWING Dimensions(mm) 54 3.46 cc(0.211cu.in.) 16.6 mm(0.654in.) 16.0 mm(0.630in.) 3,000~40,000 r.p.m. 2.4 bhp / 30,000 r.p.m. 330g(11.6oz.)(01b) 333g(11.7oz.)(01b(P)) 37 SPECIFICATIONS 4-φ3.3 101 86 21 29.5 UNF1/4-28 15 ■ Displacement ■ Bore ■ Stroke ■ Practical R.P.M. ■ Power output ■ Weight 30.6 22 (29.4) 44 101 45 21 21.6 13.
EXPLODED VIEW e C.M2.6X15 1 q 2 6 22 3 4 4 5 6-1 7 C.M2.6X18 1234567890 -=qwe = =-A - C.M2.
ENGINE PARTS LIST Description Code No. 1 2 3704 060 Heatsink Head 2 2 3703 040 Cylinder & Piston Assembly 3 2 3906 000 Piston Pin 4 2 3817 000 Piston Pin Retainer(2pcs.
CARBURETOR EXPLODED VIEW & PARTS LIST 1 1-1 1-2 2 3-1 3-2 3 3-1 3 2 3-3 3-4 3-2 6 3-3 4 3-4 7 4 5 1-1 8 1-2 5 9 0 1 - 6 7 8 9 C.M2.6X7 0 - 2 4 2 2 2 2 4 2 2 2 4 2 2 2 2 2 2 Code No. 3818 180 6066 319 2781 800 3818 500 3618 190 3618 197 6066 319 3618 194 3818 176 3818 120 5581 820 3818 251 3818 330 3818 220 2884 220 3818 400 9015 019 Description Mixture Control Valve Assembly "O"Ring(L) (2pcs.) "O"Ring(S) (2pcs.
O.S. GENUINE PARTS & ACCESSORIES RACING ENGINE PARTS ■ ■ GLOW PLUG No.8/A5 T-2030 TUNED SILENCER ■ SUPER JOINT TUBE 21 (72106300) (72106030) No.
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L I TY PRECISION & P QUA ERF ED OR M TA BL NC ES E E ANC UNEQ UA LL ISH LE EL ING THE STAN RDS OF EXC DA 6-15 3-Chome Imagawa Higashisumiyoshi-ku Osaka 546-0003, Japan TEL. (06) 6702-0225 FAX. (06) 6704-2722 URL : http://www.os-engines.co.jp C Copyright 2001 by O.S.Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan.
