Stover 20 HP Crude Oil Engine

A rare find from the 2006 Stover Reunion

| October 2006


The back end of the 1913 engine.

The extreme belching of smoke from a long, gray exhaust pipe filled the air, floating east with the breeze, as the loud clanking of the great engine beat with rhythmic precision.

A crowd inevitably gathered as owner D.W. Ruhter of Moab, Utah, started the rare engine; rare in this case meaning singular, as this is the only Stover 20 HP crude oil engine, complete and working, known to exist.

This engine, Model EL, is dated 1913, and is one of only 114 ever produced. It bears serial no. 4869L.

According to C.H. Wendel, in Power in the Past Volume 3, Stover introduced a new line of crude oil engines in 1912 ranging from 6 to 30 HP. "These semi-diesel engines were marketed for several years, but Stover production records indicate plenty of design problems along the way," Wendel writes. In his book, American Gasoline Engines Since 1872, Wendel writes that the engines were plagued with broken crankshafts, leaky shaft seals and various other difficulties.

Other models of this engine include the AL 6 HP (42 made), CL 12 HP (202 made), DL 16 HP (34 made), FL 25 HP (40 made), GL 30 HP (25 made), TEL 40 HP twin-cylinder (seven made) and the THL 60 HP twin (one made).

Wendel says the crude oil engine owed its basic design to William F. Freidag, the factory superintendent. "In July 1910, Freidag applied for a patent on his oil engine designs, finally receiving Patent no. 1,013,759 in January 1912," Wendel writes.