CATERPILLAR FUEL SYSTEMS
Caterpillar diesel engine uses the pump and nozzle injection system. Each pump measures
the amount of fuel to be injected into a particular cylinder, produces the pressure for
injection of the fuel, and times the exact point of injection. The injection pump plunger
is lifted by cam action and returned by spring action.
The turning of
the plungers in the barrels varies the metering of fuel. These plungers are turned by
governor action through a rack that meshes with the gear segments on the bottom of the
pump plungers. Each pump is interchangeable with other injection pumps mounted on the pump
metering and scroll-type pumps that are used by Caterpillar operate on the same
fundamentalsa jerk pump system (where one small pump contained in its own housing
supplied fuel to one cylinder). Individual "jerk" pumps, that are contained in a
single injection pump housing with the same number of pumping plungers being the same as
that of the engine cylinders, are commonly referred to as in-line multiple-plunger pumps.