Hello Lorenz

Welcome to these great forums.
This is a Whirlwind Rotary Scythe.

This one does not appear to be self-propelled - meaning
it's probably 20" or 24".

I would think the engine is original.
I note the PTO side is on the RH side on your machine.
That is entirely possible given these were sold over a
longer period of time - 1950s and 1960s.

Front wheels are not original.

Hope this helps.
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Jack

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