1. DL manuals
  2. O.S. Engine
  3. Engine
  4. max-21RG-M
  5. Owner's Instruction Manual

O.S. Engine max-21RG-M Owner's Instruction Manual

Summary of max-21RG-M

  • Page 1

    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 famil...

  • Page 2

    Contents safety instructions and warnings about your o.S. Engine introduction, basic engine parts installation notes concering the recoil starter glowplug tools, accessories, etc. Carburettor controls starting & initial running-in('breaking-in) adjustment 2 ~ 5 6 7 ~ 8 8 ~ 9 9 ~ 10 10 ~ 11 13 ~ 15 1...

  • Page 3: Warnings

    Remember that your engine is not a "toy", but a highly efficient internal- combustion 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 futu...

  • Page 4: Warnings

    Warnings 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. Model engine fuel is also highly flammable. Keep it away from open flame, excessive heat, sources of sparks, or anyt...

  • Page 5: Notes

    This engine was designed for model boats. Do not attempt to use it for any other purpose. Mount the engine in your model securely, following the manufacturers' recommenda- tions, using appropriate screws and lock- nuts. Fit an effective silencer (muffler). Frequent close exposure to a noisy exhaust ...

  • Page 6: Notes

    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. Warning! Immediately after a glowplug- ignition engine ...

  • Page 7: Note

    Max- 21rg-mx the o.S. "rg series" is a high-performance water-cooled marine engine for small radio- controlled boats, especially sport type hulls. A companion model, the max-21rg-mx in- corporating a recoil starter system is also available. With this engine, the piston will feel tight at the top of ...

  • Page 8: Installation of The Flyweel

    Insert the taper collet on the crankshaft, taking care not to push the crankshaft to the cover plate end. Select the screw holes according to the model. Installation of the carburetor as delivered, the engine has its carburetor lightly fitted into its intake boss. Secure it as follows. Loosen the re...

  • Page 9: Installation

    Installation make sure that the engine mounting beams in the hull are parallel, with their top surfaces in the same plane. If they are not, the engine will not rest firmly as the engine mounting faces (undersides of the mounting lugs) are precision machined to be flat and in the same plane. Poor ins...

  • Page 10: Glowplug

    ◆ ◆ note: because, in the interests of personal safety, dismantling of the starter mechanism isstrongly discouraged, the recoil starter is available for replacement only as a pre- assembled unit. However, some related parts, such as starting shaft and rear adaptor, are obtainable separately. (see pa...

  • Page 11: Tools, Accessories, Etc.

    ? when to replace the glowplug filament surface has roughened and turned white. ¡ ¡ engine tends to cut out when idling. ¡ apart from when actually burned out, a plug may need to be replaced because it no longer delivers its best performance, such as when: do not run the engine too lean and do not l...

  • Page 12

    Propeller use well balanced propellers only. As the ideal diameter, pitch and shape vary according to the size, weight and type of model, final selection can be made after practical experiment. As a starting point, suggested propeller diameter is 40-44mm with a pitch/dia ratio of 1.0-1.6 for vee typ...

  • Page 13: Carburettor Controls

    Carburettor controls the needle valve: when set to produce maximum power at full throt- tle, this establishes the basic fuel/air mixture strength. This is then maintained by the carburet- tor's automatic mixture control system to cover the engine's requirements at reduced throttle settings. The mixt...

  • Page 14

    Set the needle-valve. Turn the needle clockwise slowly, without forcing, until it stops. Then, reopen the needle-valve 2-1/2turns counter- clockwise. Open the throttle very slightly: turn needle-valve clockwise to close (for leaner mixture) turn needle-valve counterclock- wise to open (for richer mi...

  • Page 15

    Do not apply the starter to a flooded engine and never place your finger over the carburettor in- take when using the starter. This may cause an hydraulic lock and bend the connecting-rod. To stop the engine, fully close the throttle to cut off air supply. Warning: ◆ ◆ ◆ ■ in case of the 21rg-mx tak...

  • Page 16

    As with the engine of a full size boat. High r.P.M. Operation without warming up will shorten engine life or damage it. Leaving the needle-vale set at the starting setting of 2-1/2 turns open, run the boat several times with the throttle fully open until at least three full tanks of fuel have been c...

  • Page 17: Adjustment

    Adjustment running the engine with the boat out of the water, without load and without cooling water, will seri- ously damage it, due to overheating. Therefore, always lower the boat into the water immediately after the engine has been started, so as to pre- vent over-speeding and to allow cooling w...

  • Page 18

    7. Launch the boat and gradually open the throttle to its fullest extent. If at this point, the engine puffs out a good deal of smoke and does not accelerate smoothly and rapidly, it is a sign that the idling mixture is too rich. Therefore, turn the mixture control screw clockwise 45 to 60 ° . Repea...

  • Page 19: Carburettor Cleanliness

    Carburettor cleanliness proper functioning of the carburettor depends on its small fuel orifices remaining clear. The minute particles of foreign matter that are present in any fuel, can partially obstruct these orifices and upset mixture strength so that engine performance becomes erratic and unrel...

  • Page 20: Checking of The Engine

    At the end of each operating session, drain out any fuel that may remain in the fuel tank. Afterwards, energize the glowplug and try to restart the engine, to burn off any fuel that may remain inside the en- gine. Repeat this procedure until the engine fails to fire. Leaving fuel residues within the...

  • Page 21

    Symptom factor cause corrective action trouble shooting when the engine fails to start four key points for quick, reliable starting, the following four conditions are required. 1 good compression. 2 adequate "glow" at glowplug. 3 correct mixture. 4 sufficient electric starter rotating speed. If the ...

  • Page 22

    Symptom factor cause corrective action voltage too high or too low. Re-check and readjust referring to "before starting" continue to apply starter. If necessary disconnect battery from glowplug and leave for a few minutes, then re-energize plug. If engine still does not start, remove glowplug and pu...

  • Page 23: Max-21Rg-M/mx Exploded View

    4 3 2 1 c.M2.6x7 c.M2.6x18 e w q = - 0 9 8 7 6 5 4 c.M2.6x18 r t - -a t -1 t -2 y c.M2.6x7 m.+2.6x7 type of screw c … cap screw m … oval fillister-head screw f … flat head screw n … round head screw s … set screw ✽ max-21rg-m/mx exploded view 22.

  • Page 24

    7 2103 520 7 1802 030 e 2 3813 001 w 2 3607 000 q 2 3614 000 2 3813 001 y 7 3003 000 t 2 3601 800 r 2 3602 050 - 2 3430 000 0 9 2 3601 000 8 4 1614 000 7 2 3981 700 6 2 5382 000 5 2 3605 000 4 2 3817 000 3 2 3906 000 2 2 3603 000 1 2 3704 100 no. 2 3602 030 = 2 3602 000 7 1608 001 7 3003 100 7 3003 ...

  • Page 25

    No. 9 8 7 6 5 4 3 2 1 1 -1 8 8 -4 5 6 7 8 -1 8 -2 8 -3 8 -5 9 s.M3x3 1 1 -1 2 3 3 -1 4 s.M3x3 2 4981 405 2 6381 501 2 5381 203 2 6781 309 2 4881 824 2 6781 506 2 5382 100 2 5381 220 2 2681 953 2 7881 900 2 4981 959 2 4981 837 2 6381 501 2 7381 940 2 6711 305 2 9015 019 8 -1 8 -2 8 -3 8 -4 8 -5 3 -1 ...

  • Page 26

    ■ (71608001) (71605100) ■ (72403050) ■ (71530200) 1521 ■ (71521000) ■ ■ φ 3 (73300305) φ 8 (73300812) (22442009) ■ (55500002) m3 ■ (72106300) ■ (72106030) glow plug t-2030 tuned silencer super joint tube 21 crankshaft clamp long socket wrench with plug grip o.S. Genuine parts & accessories super fil...

  • Page 27

    3.46cc/0.211cu.In. 16.6mm/0.654in. 16.0mm/0.630in 3,000 ~ 35,000r.P.M. 1.7ps/28,000r.P.M. 317g/11.18oz. Japan 21 37 10.5 45 29.6 33.5 4- φ 3.3 unf 1/4-28 67 21.5 88.5 59.5 74.5 ■ ■ ■ ■ ■ ■ max-21rg-m three view drawing displacement bore stroke practical r.P.M. Power output weight specifications dime...

  • Page 28

    3.46cc/0.211cu.In. 16.6mm/0.654in. 16.0mm/0.630in 3,000 ~ 35,000r.P.M. 1.7ps/28,000r.P.M. 389g/13.72oz. Japan 40 107 45 29.6 unf 1/4-28 67 59.5 74.5 21 4- φ 3.3 10.5 33.5 37 dimensions(mm) max-21rg-mx three view drawing specifications ■ ■ ■ ■ ■ ■ displacement bore stroke practical r.P.M. Power outpu...

  • Page 29: Memo

    Memo 28.

  • Page 30

    C copyright 2001 by o.S.Engines mfg. Co., ltd. All rights reserved. Printed in japan. 090100 tel. (06) 6702-0225 fax. (06) 6704-2722 6-15 3-chome imagawa higashisumiyoshi-ku osaka 546-0003, japan u n eq ua ll ed qua lity precision & per for m an ce es ta blis hing the standards of e xce ll en ce url...