O.S. Engines FT-300 Gemini - Manual (Page 18)

1) Start the engine, with the throttle 1/3 open from the
fully closed position, then open the throttle fully and
gradually close the needle-valve until the engine is run-
ning at its maximum speed.
CAUTION: Do not close the needle-valve to too "lean" a setting as
this will cause the engine to overheat and slow down.
Set the needle-valve very slightly to the "rich" side of
the peak r.p.m. setting. Make sure that the engine is
fully "broken-in" (about 1 hour of total running time
in short runs) before operating it continuously at full
throttle.
2) Now, close the throttle gradually. The engine should idle
continuously and steadily. If it does not. adjust as
follows.
a) If the engine begins to idle unevenly, first re-open the
throttle. If the engine hesitates before picking up to
full speed, it is probable that the idling mixture is too
rich. Check this by closing the throttle again and let-
ting the engine idle for a little longer before again
opening up. If the engine now puffs out a good deal
of smoke and hesitates or even stops, it will be neces-
sary to screw out the air-bleed screw to weaken the
mixture. Do this by turning it counter-clockwise.
About 1/2-1 turn should be sufficient.
b) If, instead of being too rich, the air-bleed screw is set
too lean, the engine will stop when the throttle is
closed, or will lose speed while idling and then cut-
out abruptly (without smoking) when the throttle is
opened again. In this case, turn the air-bleed screw
about 1/2-1 turn clockwise.
3) When the mixture, has been corrected, the idling speed
will probably increase. Re-adjust the throttle opening by
means of the throttle trim on the transmitter or by
screwing-out the throttle-stop screw so that the lowest
possible idling speed, without stopping the engine, may
be obtained.
4) It is recommended to. repeat procedure 2) several times
until the best result is obtained.
Subsequent Operation and Care
Once the required carburettor settings have been establish-
ed, it should be unnecessary to alter them. Such slight
needle-valve alterations as may be needed to cope with dif-
ferences in atmospheric conditions or fuels, do not affect
the other two adjustments.
It is important that the carburettor operates under clean
conditions. Make sure that the fuel is properly filtered
before use. We advise fitting a filter in your fuel can and
another in the delivery tube between tank and engine, to
reduce the risk of the carburettor jet becoming partially
clogged and upsetting running adjustments.
Remember to clean the filters occasionally.
PARTS LIST
Code No.
46101000
46101800
46102000
46103100
45903200
46103300
45403400
46104020
46104110
46104200
46105000
45906000
46108000
45508200
46120000
46110100
46013002
46114000
26731002
22130004
46030008
46031005
22631019
46160000
Description
Crankcase
Rear Housing
Crankshaft
Cylinder Liner
Piston
Cylinder Jacket
Piston Ring
Cylinder Head (w/valve assy)
Cylinder Head
Rocker Cover
Connecting Rod Assembly
Piston Pin
Drive Washer
Woodruff Key
Thrust Washer
Propeller Locknut Set
Screw Set
Head Gasket Set
Crankshaft Bearing (front)
Crankshaft Bearing (intermediate)
Crankshaft Bearing (rear)
Camshaft Bearing (front)
Camshaft Bearing (rear)
Valve Assembly (1 pc.)
Code No.
45361000
45961400
46162000
45564000
46166000
45566100
46168000
46168500
46168100
46168200
46169000
45471000
46109400
46181000
46184000
71615009
72200060
72200040
46130000
72200080
71910000
*46110200
*72403050
Description
Rocker Arm Assembly (1 pc.)
Rocker Support Assembly
Camshaft
Cam Follower (2 pcs.)
Push Rod (2 pcs.)
Push Rod Cover Set (2 pcs.)
Intake Manifold
Manifold Seal (2 pcs.)
Intake Pipe (right)
Intake Pipe (left)
Exhaust Pipe (1 pc.)
Breather Nipple (w/gasket)
Propeller Spacer
Carburettor Complete
Choke Valve Assembly
Glow Plug Type F
Valve Adjusting Tool Kit
Booster Cable Set
Scale Propeller Washer Set
Needle-valve Extension Cable
Radial Motor Mount Set
5/16-M5(L) Propeller Lockout Set
Super Filter (large)
* Optional Parts The specifications are subject to alteration for improvement without notice.
O.S.ENGINES MFG.CO.,LTD
6-15 3-chome Imagawa Higashisumiyoshi-ku
Osaka 546, Japan. TEL. (06) 702-0225
FAX. (06) 704-2722
Copyright 1990 by O.S. Engines Mfg. Co., Ltd. All rights reserved. Printed in Japan