O.S. 140RX Ringed w/Pump

Tower Stock# LXBY54  •  Manufacturer Stock# 19221
O.S. 140RX Ringed w/Pump (large view)
Notes from our tech department:
This is the 1.40RX engine from O.S. for F3A contest flying. It conforms to the
new rules for powerplants.


Rear-mounted needle valve (attached to a bracket on the backplate)
2-needle pump carb
Integrated fuel pump (for continuous fuel flow during aerobatics)
One-piece crankcase
Designed to get the max power at low RPM (makes the engine quieter)
Extra cooling fins (helps dissipate heat)
Ringed piston
Rear exhaust
Twin ball bearing-supported crankshaft


One set of instructions, O.S. poster, and decal
One #A5 Glow Plug (OSMG2693) Heavy Duty Drive Washer
One prop nut w/locknut and spinner mount
One additional needle (with less taper)
One Heavy duty drive washer


Header (exhaust adapter) for a tuned pipe
Tuned pipe (tuned silencer - OSMG2945)
2-stroke fuel


Displacement: 1.40 cu. in.
Bore: 1.26" (32mm)
Stroke: 1.13" (28.6mm)
Practical RPM Range: 1,800 - 10,000
Max Power: 3.5 PS, 3.45 HP at 9,000 RPM
Weight (WITHOUT ANY EXHAUST): 29.3oz (840g)
Suggested Prop Sizes: 15x14, 16x14
Overall height: 4.65" (118mm)
Overall length (backplate to front of drive washer): 4.6" (117mm)
Overall width: 2.76" (70mm)
Width of crankcase only (for engine mount): 1.91" (48.4")(this is the
same mounting dimensions as the 1.20 Surpass II with pump.)
Crankshaft thread size: 5/16-24

Needle Settings: High Speed: 2 turns out from fully closed
Low Speed: Indentation on screw head vertical
(straight up and down)
JBN 8.29.96
updt lmm 3/31/09

Easy RC: Engines
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