Yanmar 3JH5E Operation Manual page 62

ENGINE OPERATION
• Are there abnormal vibrations or noise?
Excessive vibration may cause damage
to the engine, marine gear, hull and
onboard equipment. In addition, it
causes able passenger and crew
discomfort.
Depending on the hull structure, engine
and hull resonance may suddenly
become great at a certain engine speed
range, causing heavy vibrations. Avoid
operation in this speed range. If you hear
any abnormal sounds, stop the engine
and inspect.
• Alarm buzzer sounds during operation.
If any alarm indicator with audible alarm
sound appears on the display during
engine operation, stop the engine
immediately. Determine the cause and
repair the problem before you continue
to operate the engine.
• Is there water, oil or fuel leakage, or are
there any loose bolts?
Check the engine room periodically for
any problems.
• Is there sufficient diesel fuel in the diesel
fuel tank?
Replenish diesel fuel before leaving the
dock to avoid running out of fuel during
operation.
• When operating the engine at low speed
for long periods of time, race the engine
once every 2 hours.
56
Racing the engine: With the gear in
NEUTRAL, accelerate from the
low-speed position to the high-speed
position and repeat this process about
five times. This is done to clean out
carbon from the cylinders and the fuel
injection valve. Neglecting to race the
engine will result in poor smoke color
and reduce engine performance.
• If possible, periodically operate the
engine at near maximum engine speed
while underway. This will generate
higher exhaust temperatures, which will
help clean out hard carbon deposits,
maintaining engine performance and
prolonging the life of the engine.
Never turn off the battery switch (if
equipped) or short the battery cables
during operation. Damage to the electric
system will result.
JH Series Operation Manual