Jim O’Clair on at 4:00 pm
We spotted an interesting item that was recently sold on an online auction site, a Willys-Knight Moving Piston Sleeve Cutaway Demonstrator model. The model has a knob on the back of the unit for rotating the cylinder, so that the operator can see the motion of the mobile cylinder sleeve “valves” as they travel up and down in the cylinder bore. Invented by Charles Knight in 1905, this design was said to reduce engine friction by moving an intake and exhaust sleeve during the power and compression strokes to open and close the intake and exhaust ports, instead of using a more traditional overhead or side-valve system.
Ray Bohacz wrote a story about this odd engine configuration in the December 2010 issue of Hemmings Classic Car entitled Silent Knight.
The sleeve valve design was not used exclusively by Willys-Knight, but was licensed to many other engine manufacturers including Mercedes, Panhard, Daimler and Minerva of Belgium. Willys produced both four and six-cylinder sleeve valve engines that were used in its vehicles as well as in Federal trucks during the twenties and thirties. Several engines of the era were labeled with the “-Knight” nomenclature, including Daimler-Knight and Moline-Knight because of the licensing agreements. This demonstrator is an interesting piece of automotive history, and it sold for $530.00.