O.S. FS155-a Pumped 4-Stroke

200-size power in a 120-size package!

How do you get 200-size power from a 120-size engine? O.S. calls it the FS155-a. Since the FS155-a is a pumped 4-stroke, you’ll enjoy 2.6 hp at all times, regardless of tank position, attitude or fuel level. Its novel recirculation system bathes working parts in constant lubrication, for less friction and wear!
Specifications:
Displacement: 1.548 cu in (25.6 cc) RPM Range: 2000-11000 Output: 2.6 hp @ 10,000 rpm Weight with Muffler: 31.7 oz (900 g)


O.S. Two Year Limited Warranty
  • Also included: F-6020 muffler, Type F glow plug & PD-08 pump.
  • The same 2.6 horsepower as many 200-size power plants — with the dimensions and weight of a 120-size engine.
  • Because it’s a pumped 4-stroke, you’ll enjoy plentiful power regardless of tank position, attitude or fuel level.
  • Instead of oil venting through the crankcase, it’s re-circulated to lubricate working parts — reducing friction and wear as well as cowl cleanup.
  • Includes the 70R regulating carb for superior throttle response and precise fuel metering.
  • 2-year limited warranty.
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