In 1927, the Willys-Overland Motors saw a groundbreaking addition with the introduction of the Type 56, a luxurious sedan featuring a six-cylinder Silent Knight sleeve-valve engine equipped with a rectifier. Willys, an early American manufacturer, had used the Knight engine in its lineup since 1914. However, the innovative step of adding a rectifier was aimed at addressing the sleeve-valve engine's notoriety for excessive oil consumption that resulted in a distinctive trail of blue smoke.
Willys-Knight ingeniously tackled the oil consumption issue by directing excess oil through openings in the cylinder wall near the exhaust port. The resulting mixture of oil and gasoline was then channeled to the rectifier, where distillation occurred in a chamber heated by exhaust gas. This unique process allowed the return of oil to the crankcase, while expelling gasoline fumes through the exhaust pipe. Despite its clever and effective design, the rectifier was not incorporated into engines used in Europe.
This is a popular vehicle for Jeep enthusiasts who visit. As we like to point out, this is the "Grandmother of the Jeep," and is an interesting piece of automotive history.
Become an archive member for exclusive access to photos, videos and historical documents about the museum's car collection.
