Bleeding The Fuel System - Yanmar 4JH45 Operation Manual

BEFORE YOU OPERATE

Bleeding the Fuel System

The fuel system has an automatic air
bleeding device that purges air from the
fuel system. No manual air bleeding is
required for normal operation. Bleeding
must be done if any fuel system
maintenance has been performed
(replacement of fuel filter, etc.) or if the
engine does not start after several
attempts.
The fuel system needs to be primed under
certain conditions:
• Before starting the engine for the first
time.
• After running out of fuel and fuel has
been added to the fuel tank.
• After fuel system maintenance such as
changing the fuel filter and draining the
fuel filter/water separator, or replacing a
fuel system component.
WARNING
Fire and Explosion Hazard!
• Diesel fuel is flammable and
explosive under certain conditions.
• Failure to comply could result in
death or serious injury.
Exposure Hazard.
Always wear safety glasses when
bleeding the fuel system.
40
Bleeding the pre-filter
Figure 4
1 – Priming Pump
2 – Air Bleed Screw
1. Check the fuel level in the fuel tank.
Refill if necessary.
2. Open the fuel cock of the fuel tank.
3. Loosen the air bleed screw
(Figure 4, (2)) two to three turns.
4. Push up and down on the priming
pump (Figure 4, (1)) to release air out
of the air bleed screw.
5. Continue pumping until a stream of fuel
with no air bubbles begins to flow.
(approx. 60 times.)
6. Tighten the air bleed screw.
JH Series Operation Manual
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056904-02X00