Fuel Injection Pump
Turbo models have a connection from the turbocharger to the altitude compensator which allows the unit to enrich the mixture during boost operation.
The 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 shut-off stops fuel delivery when the ignition switch is turned to the "OFF" position. If it fails, a manual "STOP" lever is provided on the side of the pump.