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Fuel Injection Pump

Fuel pump must deliver under certain pressure and without air bubbles. Insufficient pressure can cause engine problems. Pressure is kept constant by a by-pass valve which is installed in main fuel filter and opens at pressures between 14.7-22.0 psi (1.03-1.50 kg/cm2 ).

The vacuum shutoff stops fuel delivery when ignition switch is turned to "OFF" position. If it fails, a manual "STOP" lever is located on side of pump. A mechanical fuel pump draws fuel from tank and supplies it to high pressure section of injector pump. Pump is lubricated by engine oil.

Fig 1: Fuel Injection Pump Components
G34656