Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Bonjour Hans,

Among others I have the M91 and also had to solve several issues.

My question is : What do you mean when you write "What I can't seem to solve is spray coming from the inlet ('carburetor') during the hits." ? Sorry, my English is not my native langage   

What could this spray made of because for me a spray is the vaporization of a liquid ? And there is no link between the inlet valve and the carburetor

To my opinion, if you had a leaking outlet valve, your engine would not run and you should feel almost no pressure when you turn it by hand ? => Do you feel a pressure ?

Other test I would kindly suggest you to close the carburetor with your finger and turn the engine in its direction of travel, you should feel a suction => Do you feel it ?

Do you see the spark at top dead center ? This confirms it starts on the correct timing side

And if you could make a little video of your issue, it would greatly help us to analyze it