Chapman Fuel System

The Chapman Fuel System

Intake stroke, piston is pulled down in cylinder, creating lower pressure in combustion chamber, inake valve opens, allowing higher pressure air in fuel tank to push fuel up through checkball 'D' and up pipe 'B'. This same unbalance of pressures (higher outside pressure than in combustion chamber and head) pushes checkball 'E' closed (or allows it to drop into seat). Fuel is pushed up into pipe until it causes float 'C' to move upward, and close off the opening to pipe 'A'.

Compression stroke, piston moves upward in cylinder, valve closes causing the loss of lower pressure at pipe 'A'. Pressures in pipes equalize, causing fuel in pipe to fall, closing checkvalve 'D'. Fuel then unseats checkvalve 'E' and drops into fuel chamber 'G'. Excess fuel returns to fuel tank in base of engine via pipe 'F'. Float is heald up in position in pipe by "stop pin".

OK, so Walt Disney I'm not!

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