Yanmar 3JH4E Service Manual page 39

Fuel System Air bleeding Procedures
1) Check the fuel level in the fuel tank. Replenish if
Insufficient.
2) Loosen the air bleeding bolt at the top of the fuel/
water separator by turning it 2 or 3 turns. When
fuel, which does not contain air bubbles, comes
out of the bolt hole, tighten the air bleeding bolt.
3) Loosen the air bleeding bolt of the fuel filter by
turning it 2 or 3 turns.
4) Feed fuel with the fuel feed pump by moving the
lever on the left side of the feed pump up and
down.
5) Allow the fuel containing air bubbles to flow out
from the air bleeding bolt hole. When the fuel no
longer contains bubbles, tighten the air bleeding
bolt. This completes the air bleeding of the fuel
system.
6) After the engine start-up, the automatic air-
bleeding device works to purge the air in the fuel
system. No manual air-venting is required for
normal engine operation.
(2) Check the electrolyte level in the battery
Fire due to electric short-circuit
• Make sure to turn off the battery switch or disconnect the negative cable
(-) before inspecting the electrical system. Failure to do so could cause
short-circuiting and fires.
• Always disconnect the (-) Negative battery cable first before
disconnecting the battery cables from battery. An accidental "Short
circuit" may cause damage, fire and or personel injury.
And remember to connect the (-) Negative battery cable (back onto the
battery) LAST.
Proper ventilation of the battery area
Keep the area around the battery well ventilated, paying attention to keep
away any fire source. During operation or charging, hydrogen gas is
generated from the battery and can be easily ignited.
Do not come in contact with battery electrolyte
Pay sufficient attention to avoid your eyes or skin from being in contact
with the fluid. The battery electrolyte is dilute sulfuric acid and causes
burns. Wash it off immediately with a large amount of fresh water if you
get any on you.
23
2. Inspection and Adjustment
Fuel nozzle
Fuel feed pump
Air bleeding bolt
To fuel tank
Fuel filter
Fuel injection
pump