This allowed the engine to run on its own lubricating oil when the throttle was in idle position.
"The First Airplane Diesel Engine: Packard Model DR-980 of 1928"
Robert B. Meyer
Any excess lubricating oil in a diesel engine's cylinder is consumed cleanly to produce power.
"The First Airplane Diesel Engine: Packard Model DR-980 of 1928"
Robert B. Meyer
Many operators have found that the sale of gasoline and lubricating oil and tobacco in various forms can be offered for sale to good advantage simply as a part of the service being offered by the market to the public.
"A Living from the Land"
William B. Duryee