Inspection Every 50 Hours Or Monthly - Yanmar 3YM30 Sevice Manual

2. Inspection and adjustment
(7) Adjust the propeller shaft alignment
The flexible engine mounts is compressed a little in the initial engine operation and it may cause the
centering misalignment between the engine & the propeller shaft.
1) Check unusual noise and vibration of the engine / boat hull, while increasing the engine speed
gradually and lowering it.
2) If there is unusual noise and/or vibration, adjust the propeller shaft alignment. (Refer to 6.4.5
"Centering the Engine" in the installation manual for pleasure boat use.)

2.2.3 Inspection every 50 hours or monthly

Be sure to check the following points every 50 hours or monthly, whichever comes first.
No.
(1) Drain the fuel filter
(2) Check the electrolyte level in the battery
(1) Drain the fuel filter.
1) Close the fuel cock of a fuel tank.
2) Loosen the retaining ring and remove the filter cap.
Drain off any water and dirt collected inside.
3) After reassembly, be sure to vent air from the fuel
system.
If air is in the fuel system, fuel cannot reach the
fuel injection pump. Vent the air in the system
according to the following procedures.
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
filter by turning it 2 or 3 times.
3) Feed fuel with the fuel feed pump by moving the
lever on the left side of the feed pump up and
down.
4) 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.
5) 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.
Inspection Item
25
Air bleeding
Bracket
O-ring
Filter element
Filter cap
Retaining ring
(Fuel filter)