3054B Engine for Caterpillar Built Machines Caterpillar

If air enters the fuel system, the air must be purged before the engine can be started. Air can enter the fuel system when the following events occur:

• The fuel tank is empty or the fuel tank has been partially drained.

• The low pressure fuel lines are disconnected.

• A leak exists in the low pressure fuel system.

• The fuel filter is replaced.

Use the following procedures in order to remove air from the fuel system:

1. Fuel filter and venting the fuel filter on Lucas fuel systems
   Show/hide table

   Illustration 1	g00310885
   Fuel filter and fuel filter base (Lucas Fuel Systems) (1) Vent plug (2) Fuel filter and fuel filter base

   Show/hide table

   Illustration 2	g00310703
   (3) Fuel transfer pump

   1. Loosen vent plug (1) on top of the fuel filter and filter bases. Operate the priming lever on the bottom of fuel transfer pump (3) until fuel, which is free of air, flows from the vent plug.

   2. Tighten the vent plug.

2. Fuel filter and venting the fuel filter on Stanadyne fuel systems
   Show/hide table

   Illustration 3	g00310963
   Fuel filter and filter assemblies (Stanadyne Fuel System) (1) Vent plug for the fuel filter (if equipped) (2) Vent plug for the fuel filter

   Show/hide table

   Illustration 4	g00310703
   (3) Fuel transfer pump

   1. Loosen vent plug (1) on top of the fuel filter base. Operate the priming lever on the bottom of fuel transfer pump (3) until fuel, which is free of air, flows from the vent plug.

   2. Tighten vent plug (1).

   3. Loosen vent plug (2) on top of the fuel filter. Operate the priming lever on the bottom of fuel transfer pump (3) until fuel, which is free of air, flows from the vent plug.

   4. Tighten vent plug (2).

      Note: If the drive cam of the fuel transfer pump is in the position of maximum cam lift, the priming lever will not operate. The crankshaft must be rotated one revolution.

   Show/hide table

   Illustration 5	g00311106
   (4) Nut for the fuel line to the air inlet heater

3. If the fuel line for the air inlet heater has been drained, loosen fuel line nut (4) at the air inlet heater. Operate the priming lever on the bottom of fuel transfer pump (3) until fuel, which is free of air, flows from the fuel line. Tighten fuel line nut (4) to a torque of 22 N·m (16 lb ft).
   Show/hide table

   Illustration 6	g00311183
   (5) Nuts for the fuel line to the fuel injection nozzles

4. Loosen the connections for the high pressure fuel lines on two fuel injection nozzles. Operate the electric starting motor until fuel, which is free of air, flows from the fuel line. Tighten fuel line nuts (5) to a torque of 22 N·m (16 lb ft).

   Note: Damage to the fuel injection pump, the battery, and the electric starting motor can occur if the electric starting motor is used excessively to purge the air from the fuel system.

5. The engine is now ready to start. If the engine stops or if the engine runs roughly, check for air in the fuel system. If air is in the fuel system, leakage in the low pressure fuel system probably exists.

   Note: Operate the engine at low idle for a minimum of five minutes immediately after air has been removed from the fuel system. Running the engine for this period of time will help ensure that the pump is completely free of air. Damage to the internal parts of the pump which is caused by metal to metal contact will be prevented.