C Series Fuel System - Overview Section F - Familiarization Page F-3 Fuel System - Overview (005-999) General Information The function of the fuel system is to inject a metered quantity of clean atomized fuel into the engine cylinders at a precise time near the end of the compression stroke. The components of the fuel system contribute to the delivery of fuel to the cylinders. 1. Fuel injection pump 2. High-pressure fuel lines 3. Injectors. 1. Fuel injection pump 2. Fuel supply line 3. Fuel filter 4. Fuel transfer pump 5. Fuel tank ( not shown) 6. Fuel return line. The fuel transfer pump is mechanically driven by a plunger running against a special lobe on the camshaft.
The fuel transfer pump contains a pumping piston (A) and check valves (B) (C) to control the flow of fuel and bleed back during engine shutdown. 1. Low-pressure supply line 2. Priming pump 3. Fuel inlet line 4. Plunger. The pressure relief valve arrangement in the supply side of the fuel circuit creates a self-bleeding system on the A- type fuel injection pump. Air introduced during replacement of any supply-side components will automatically bleed out of the fuel system. Small amounts of air can be bled from the fuel injection pump by operating the hand primer on the fuel transfer pump or by cranking the engine.