Jump to content

D-400 engine

From Wikipedia, the free encyclopedia
D-400 series engine
Restored Masport Iron Horse engine
Overview
ManufacturerOutboard Marine Corporation (OMC)
Lawn-Boy
Also calledIron Horse
Production1954--1977
Layout
ConfigurationSingle-cylinder 2-stroke
Displacement108.99 cc (6.651 cu in)[1]
Cylinder bore60.325 mm (2.3750 in)
Piston stroke38.1 mm (1.50 in)
Cylinder block materialAluminum
Cylinder head materialAluminum
Compression ratio4.5:1
Combustion
Fuel systemFloat carburetor
Fuel typePetrol
Oil system16:1-32:1 pre-mixed fuel:oil mix
Cooling systemAir-cooled
Output
Power output3.5 hp (2.6 kW)[1]
Chronology
SuccessorD-600

The D-400 series engine or the Iron Horse engine was a light-duty two-stroke engine used for powering lawnmowers produced from the 1950s to the late 1970s. D-400 engines were single-cylinder engines designed and manufactured by the Outboard Marine Corporation (OMC; Johnson and Evinrude) for Lawn-Boy[2] and Masport. The D-400 engines displaced 109 cc, generated 3.5 hp (2.6 kW) of power, and operated in the range of 2400-3300 RPM.[1][3]

Description

[edit]

The engines have a distinctive rectangular cowling that has created a nickname of brick-top mowers. Another distinctive feature is the two-finger vertical recoil starter.[3] The kidney-shaped muffler and exhaust unit is mounted beneath the mowers' deck and gives the engine a small, low profile design when compared to the newer and more powerful lawnmower engines. The ignition system employs a magneto, points, and a condenser (capacitor) set-up with an unusual spark-advance system which utilised a weight on the crankshaft to adjust the spark-advance amount depending on engine speed. The sprung governor was also unusual with a throw-yoke which operated under the flywheel and was linked to the throttle. The carburetor was a float design and fed into a pair of reed valves.

In New Zealand and Australia, Masport also known in New Zealand as "Charlie Gamble" offered the D-400 engine on their Premier, Premier II, Rancher, Rotacut, and Tornado models.[4] In this Oceania market, the D-400 was called the Iron Horse engine.

References

[edit]
  1. ^ a b c Lawn-Boy (1983). "Lawn-Boy Service Manual 1950--1983". Retrieved 2012-02-04.
  2. ^ "Lawn-Boy brand history". 2012. Archived from the original on 2012-02-13. Retrieved 2012-02-04.
  3. ^ a b "Lawn Boy Engine series". 2008. Retrieved 2012-02-04.
  4. ^ "Moving Up to Masport TV Commercial [sic] (1972)". 2011. Retrieved 2012-02-04.