Balance point diagnostics for internal combustion engine

Abstract

As used herein, the term 'power' means a factor indicative of or related to horsepower, computed from acceleration and speed, with or without an empirically-determined inertia constant. A measurement of the operation of the governor of an internal combustion engine, such as a diesel engine having a primary distributing pump for providing fuel in a time related fashion to the fuel injectors, and in which fuel pressure is not an indication of governor operation, is the speed at which a line defined by two points measured on the power/speed characteristic of the engine intersects with an empirically-determined line emanating from the measured high idle speed point on the zero power speed abscissa of the power/speed characteristic. Two power measurements, each including time and speed, are made at different speeds as the engine accelerates with only its own drag, inertia and accessories as loads thereon. The difference therein, with or without horsepower calculations using an empirically-determined inertia constant, over the difference in speed provides the slope of an idealized, straight-line power/speed characteristic. An empirically-determined slope, with or without correction for the actual high idle speed measured, defines a second, idealized straight line indication of governor action in limiting fuel at high idle speed. From simply geometry, the intersection of these two straight line power/speed related representations is found as a measure of the balance point speed which is the speed at which the governor action begins.