Gas Engine Propane Demand Valve Drawing

Best described by one of Jerry's good friends:

"Propane is burned in some miniature engines rather than gasoline or alcohol. The exhaust produced is not as offensive and the engine runs cleaner. Small propane cylinders are used. A pressure regulator is fastened to the bottle to allow a regulated flow. The flow is then attached to the inlet side of the demand valve where it cannot escape. The outlet side of the demand valve is attached to the engine carburetor. During the intake stroke of the engine a vacuum demand is created. This demand (suction) trips the needle in the demand valve and allows a flow of propane to the engine. When the demand stops so does the propane flow. Scuba divers have a similar device on their tanks to allow a flow of air on demand." - Chuck Harty

Notice: The improper handling and use of propane can be hazardous! Conversely, when proper care and precautions are taken and common sense is used, it can also be very safe.

Disclaimer: These drawings are for basic information only and are not intended to be "plans for construction".  These drawings represent what the author has done and we have no way to supervise your design, workmanship or selection of materials. If you purchase these drawings and/or make any similar devices based on these drawings, you agree we will not be held responsible in any way if for any reason an accident occurs.

One sheet with drawings, assembly and operation notes.