I finally started working on Clerget engines family (9B, 9BF, 9Z and 9N). I'm still waiting for a book (Clerget Patent Aero Engines: Instructions and List of Parts) to have exact dimensions of the engine. To tell you the truth it's the only obstacle, that hamper starting crankcase. Maybe somebody has any plans or dimensions of this engine? It's difficult to measure it in museum, as far as crankcase is concerned.
I'd be grateful for your help.
All the best, Lukasz