Bleeding the Fuel System

Any time the fuel system has been opened up for service (lines disconnected or filters removed), it will be necessary to bleed air from the system.

The fuel system must also be bled whenever the fuel tank has been run dry.

To bleed the fuel system, proceed as follows:

2. Operate fuel supply pump primer lever (B) until fuel flow is free of air bubbles.

3. Tighten bleed screw securely, continue operating primer until pumping action is not felt. Push hand primer inward (toward engine) as far as it will go.

4. Start engine and check for leaks.

5. If engine will not start, it may be necessary to bleed air from fuel system at fuel injection pump or injection nozzles as explained next.

A-Bleed screw
B-Lever

OUCC020,0002035 -19-24MAR05-1/3

• At Fuel Injection Pump:

  a. Slightly loosen fuel return line connector (C) at fuel injection pump.
  b. Operate fuel supply pump primer lever until fuel, without air bubbles, flows from fuel return line connection.
  c. Tighten return line connector to 16 N·m (12 lb-ft).
  d. Leave hand primer in the inward position toward cylinder block.
  

• At Fuel Injection Nozzles:

  a. Using two open-end wrenches, loosen fuel line connection at injection nozzle.
  b. Crank engine over with starting motor, (but do not start engine), until fuel free from bubbles flows out of loosened connection. Retighten connection to 27 N·m (20 lb-ft).
  c. Repeat procedure for remaining injection nozzles (if necessary) until all air has been removed from fuel system.
  

If engine still will not start, see your authorized servicing dealer or engine distributor.

C-Return line connector

OUCC020,0002035 -19-24MAR05-2/3

Fuel System (3220 and 3420)


Any time the fuel system has been opened up for service (lines disconnected or filters removed), it will be necessary to bleed air from the system.

The fuel system must also be bled whenever the fuel tank has been run dry.

To bleed the fuel system, proceed as follows:

1.

Loosen the bleed screw (A) two full turns by hand on final fuel filter base.

2.

Operate fuel supply pump primer lever (B) until fuel flow is free of air bubbles.

3.

Tighten bleed screw securely, continue operating primer until pumping action is not felt.

4.

Start engine and check for leaks.

If engine will not start after this bleeding procedure, repeat the procedure.


A-Bleed screw
B-Lever

Bleed Screw on Final Fuel Filter

OUCC020,0002035 -19-24MAR05-3/3