Bonjour,
I have several of these engines and for them, I tried Zippo gas but VERY expensive so now I use SP98 gasoline with a drop of 2 stroke oil.
I find them very difficult to settle and their behaviour changes when they heat.
To be able to start them with the hand suppose Gil's skillness (he helped me for my M91)
And I do not know if the water pump is really useful as it is very fast :