The Natural Philosopher gurgled happily, sounding
much like they were saying:

Despite all the naysayers I still reckon this idea has legs. Average
small car must develop 50hp +? Thats going to run a hell of a lot more
than any inverter ever could.

Not a 2CV.

30bhp.

AND certainly NOT running static with no airflow round the engine.

You'd be fine - the fan generates enough cooling whilst the engine's
static, assuming the oil cooler's kept properly cleaned.

I'd be more concerned by running it with just one wheel acting as a PTO -
that's going to put a lot of unusual load on the diff.

Buying (or making - a 2cv engine in a cradle with the flywheel driving a
pump directly...?) a cheap petrol generator seems like a much better plan
to me.