Bleed the Fuel System - Engine using ECU

NOTE: This fuel system can only be bled by the electric transfer pump or at the injection nozzles. Bleeding should not be performed at any location on the Bosch VP44 injection pump.

Bleed Using Electric Transfer Pump

Bleeding is automaticaly performed by a small orifice (A) inside the filter base connected to the overflow valve (B) on injection pump. This system allows air to escape continually through the fuel return line (C) when ignition is ON.

1. Ignition ON.
2. Allow 40 seconds for electric transfer pump to complete priming.
3. If additional system bleeding is required, bleed the circuit by loosening fuel line connections at injection nozzles.


A-Bleed Orifice in Filter Base
B-Overflow Valve
C-Fuel Return Line

CQ213190
CQ213180

Injection pump (VP44)

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Bleed at Fuel Injection Nozzles

1. Place throttle lever in half-throttle position.

On engines equipped with electric fuel shut-off solenoid, energize solenoid.

IMPORTANT: Always use a backup wrench when loosening or tightening fuel lines at nozzles and/or injection pump to avoid damage.


2. Using two open-end wrenches, loosen two fuel line connections at injection nozzles.
3. Crank engine over with starting motor for 15 seconds (but do not start engine) until fuel free from bubbles flows out of loosened connection. Retighten connection to specifications.
Fuel Injection Nozzle Delivery Lines Torque 27 N.m (20 lb-ft)
4. Repeat procedure for remainig injection nozzles (if necessary) until all air has been removed from fuel system.

RG7725

Nozzle Fuel Pressure Line

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