Poppet-Valved Martin Outboard Motors of Eau Claire

Martin Outboard MotorWARSAW, Virginia – On display in the window of this Northern Neck town at The Daily coffee shop is a snazzy Martin “40” outboard motor. Once, there were many American outboard brands. While Evinrude, Johnson and Mercury survive, Martin did not.

Martin Motors was from Eau Claire, Wisconsin. This motor was made when the brand was part of the National Pressure Cooker Company. Apparently Martins were made from 1946 to the early 1950s, and had “poppet” valves.

Can someone please explain poppet valves?

The brand survives today; Larson Outboard apparently owns the blueprints and supplies parts for the old ones.

Over the years there have been dozens of motor brands sold in the U.S., including Chrysler Marine, Perkins, Rootes, Oliver, Flambeau, Champion, Sea Flyer, Elgin, Scott-Atwater, Lauson, Neptune, Reily, West Bend and Hiawatha. My cousin Mark is a big fan of British Seagull engines.

Any memories of vintage outboards? And what brands were noted for styling, technological innovation, durability and economy?



  1. Poppet valves are the trumpet-bell-shaped valves used in most 4-cycle engines, usually in or near the cylinder head . What made the Martin engines unique is that they are a 2-cycle engine that uses a single poppet valve in the crankcase at the bottom of the crankshaft stroke. Most 2-cycle engines use reed valves to admit the air/fuel mixture into the crankcase. This design requires a lot of quick fluctuation in crankcase pressure, thus 2-cycle engines run more smoothly at higher RPM’s than do 4-cycle. George Martin’s poppet-valved 2-cycle design would idle more smoothly and at lower engine speeds than his competitor’s engines. Lower engine speeds meant quieter boats, and they were hugely popular with freshwater sport anglers.
    George Martin was very much the Preston Tucker of the outboard boat engine business, and American Business just won’t have any of that.

  2. Mike..thanks for the comments. And isn’t it sad that the Preston Tucker’s don’t reap the rewards, even though they are remembered well after their time.

    Jo –thanks for video. Love the idea of racing vintage boats.

  3. Don’t know much about the 4 h.p. but the 7 h.p. poppet valves were operated by a rocker arm and the crankshaft had a cam that open the valve.

  4. My father, Sam Welch, was the advertising manager for Martin Motors — start to finish. Dad took me to many outboard racing events back in the early 1950s. I ‘ve got a Martin 75 — near A-one condition — mounted on a stand. Every time I pass by it, I pet the poppet valves. I recently came across a photo on my computer of a boat driven by a Martin 6O outboard. The location ? Just off the salt-water coast of Italy!
    Quite a few Martins made their way to European boat owners…

  5. When I purchased a used boat, it included a Martin “75” outboard, and it was used as a trolling motor because of how smoothly and quietly it ran. It was still running in 2004 when the boat was sold. I kept the Martin motor because I liked it, but have not used it since. It is still in great shape, much like the picture above. If anyone is looking to acquire one of these, I might be persuaded to part with it.

Leave a Reply

Your email address will not be published. Required fields are marked *