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Muncie Gear Co. Neptune OA2 ?


I was wondering if anyone has information on a Neptune Model OA2 single cylinder boat motor. I seem to only find info beginning with models OB. The serial number is 29582C2


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There sure seems to be a shortage of info on these motors. I have an OB2, a twin cylinder from about 1937. The only manufacture date I could come up with was based on the Tillotsen carburetor model. Mine appears to have the same Eisemann magneto used on Maytag motors. I think the magneto coil is weak and prone to failure so treat it carefully by never pulling a spark plug wire and leaving a large spark gap to jump. My motor has no clutch or reverse gear but the magneto has an advance/retard lever. I wonder if reverse was somehow achieved by retarding the spark although the rope start pulley only allows starting in one direction. I think mine is around 2 hp and it runs well.



a friend of mine had a old single Neptune when I was a kid, the little bugger always ran and good to....:D