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Dale Detrich                     Attica, OH                 djdtrh@cros.net

The gearless hit and miss engine was the first i.c.engine that i built,  first reason that i built this engine was that i did not have much in the way of tooling. i had a basic three in one machine. second reason was that the plans were free, being a five issue project in home shop machinist. the engine was designed by Philip Duclos, and the plans were clear and easy to follow. the engine has a basic vertical set up , except the drive between the crankshaft and valves. intake valve is spring loaded atmosphere operated, the exhaust valve is pushrod operated from a single lobe cam. the two to one ratio between crank and valve is achieved  by a tumbling block on top of the pushrod. this block has two short arms and two long arms, when the pushrod is lifted by the cam and one of the long arms is in the up position the exhaust valve is operated. on the down stroke of the pushrod , the block is rotated 90 degrees ,so the next time the pushrod is lifted the exhaust is not operated. this tumbling action pro
vides a two to one ratio between crank.  the engine has a spring loaded governor which keeps the engine at aprox.900 RPM.                bore..  .750"
 stroke........1.125"         fuel ...............40 to 1  pump gas and 2 cycle oil                ignition..........12 volt point operated              the engine with the tumbling  block valve operation is eye catching and fun to watch, the engine is now aprox six years old . the engine runs trouble free, and some times for hours at a time  

          

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