Bleeding Fuel System

CAUTION: Escaping fluid under pressure can penetrate skin causing serious injury to you or others. Avoid hazard by relieving pressure before disconnecting hydraulic or other lines. Tighten all connections before applying pressure. Search for leaks with a piece of cardboard. Protect hands and body from high pressure fluids.

If an accident occurs, see a doctor immediately. Any fluid injected into the skin must be surgically removed within a few hours or gangrene may result. Doctors unfamiliar with this type of injury should reference a knowledgeable medical source. Such information is available from Deere & Company Medical Department in Moline, Illinois, U.S.A.

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

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On final fuel filter:

Drain water out of filter by opening drain plug (B). Close plug once pure fuel is coming from plug.

Open air bleed vent screw (A) two full turns by hand.

Pump hand primer (C) on fuel supply pump until a noticeable amount of fuel and air comes out of vent opening. Close vent screw when fuel only starts to flow.

Pump hand primer several times until resistance is felt. Open air bleed vent screw.

Close air bleed vent screw and pump hand primer several times until resistance is felt again.

On primary fuel filter (D):

Drain at plug (E) using gravity or pressure to tank.

Previous to bleeding fuel system make sure fuel tank is full and that machine is parked on incline with rear of machine up.

A-Vent Screw
B-Drain Plug
C-Hand Primer
D-Primary Fuel Filter
E-Drain Plug

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On injection pump:

Loosen fuel return line (A) at fuel injection pump.

Operate fuel supply pump primer lever.

As soon as fuel flow is free from air bubbles, tighten fuel return line to specification.

Specification

A-Fuel Return Line

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If engine misses after bleeding filter, perform following directives:

Loosen high-pressure fuel pipe (A) on three or more injectors (B), using two wrenches.

Disconnect alternator wire from injection pump to keep engine from firing.

Operate key switch to turn engine until fuel flows WITHOUT BUBBLES from loose connections.

Tighten connections using two wrenches.

Bleed remaining injectors similarly. It is sometimes necessary to bleed injectors with engine running.

Reconnect alternator wire.

A-High-Pressure Fuel Line
B-Injectors

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