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Diesel Injection Pump

The high pressure diesel injection pump is mounted at top of engine, below intake manifold. The pump is gear driven by camshaft. Pump precisely governs time and amount of fuel injection.

A built-in fuel pressure regulator and transfer pump picks up fuel at pump inlet, pushing it through a passage to the pump head. The pump head distributes fuel at transfer pump pressure 8-12 psi (.5-.8 kg/cm2 ) to metering valve, governor and automatic advance mechanisms. Fuel then passes to rotary fuel metering valve and into a charging passage. As pump shaft rotates, fuel is directed at high pressure through each delivery pipe to an injector.

Fig 1: Diesel Injection Pump
G72717Courtesy of GENERAL MOTORS CORP.