In Stock
Brand Logo
3.9 out of 5 Customer Rating

FS155-a Alpha Series 1.55 4-Stroke Pumped Engine

Item No.
OS Engines - OSMG0998
$599.99
In Stock
Brand Logo
3.9 out of 5 Customer Rating

FS155-a Alpha Series 1.55 4-Stroke Pumped Engine

Item No.
OS Engines - OSMG0998
$599.99
Product $599.99
Add Ons
Estimated Total: $599.99

FS155-a Alpha Series 1.55 4-Stroke Pumped Engine

Item No.
OS Engines - OSMG0998
3.9 out of 5 Customer Rating
Product $599.99
Add Ons
Estimated Total: $599.99
Earn points on this item
Selected Store

Product Details

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!


O.S. Engines 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.

Product Specifications

Manufacturer # 35430
Product Height 5.4 in (138.6 mm) from bottom of crankcase to rocker cover
Prop Range 16 x 8 - 17 x 12
RPM Range 2,000 - 10,000 rpm
Engine (Only) Weight 28.4 oz (805 g)
Displacement 1.548 cu in (25.36 cc)
Cylinders Single
Product Width 2.6 in (67 mm) at mounting tabs
Total Weight 32oz (900g)
Muffler Weight 3.35 oz (95 g)
Crankshaft Threads UNF5/16-24
Bore 1.32 in (33.6 mm)
Power Type Glow
Plug Type Type F glow plug
Stroke 1.13 in (28.6 mm)
Product Length 5.0 in (127.5 mm) from carburetor to drive hub