I have one of each not restored as yet
These two mowers have a lot difference
The 4 Star has a Lauson engine
The 4 Stroke has a Kirby-Lauson engine with the only difference in appearance is the Lauson engine has a oval air cleaner where the Kirby-Lauson engine has a round one
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The 4 Star engine has no gape from engine to base where the 4 Stroke does
[Linked Image]
[Linked Image]
The base is also a different shape. In the GREEN book it show the 2 bases
The 4 star base is more of a square look where the 4 Stroke is more rounded
[Linked Image]
[Linked Image]
The under side of the base is also different
The 4 Star has ribs the 4 Stroke does not
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[Linked Image]
The throttle on the 4 Stroke is not original the last owner fitted it
These mowers most likely come under the heading of being a SHEERLINE
Ian