Yanmar 1GM10 Operation Manual page 41

3. Check that the exhaust color, engine
vibration and sound are normal.
4. When there are no problems, keep the
engine at low speed with the boat still
stopped to distribute engine oil to all
parts of the engine.
5. Check that water is being discharged
from the seawater outlet pipe.
Operation with inadequate seawater
discharge will damage the impeller of
the seawater pump. If seawater
discharge is too low, stop the engine
immediately. Identify the cause and
repair. NOTICE: The engine will seize
if it is operated when cooling
seawater discharge is inadequate
or if load is applied without any
warm-up operation.
• Is the seacock open?
• Is the inlet of the seacock on the hull
bottom clogged?
• Is the seawater suction hose broken
or does the hose suck air because of
a loose clamp?
GM Series Operation Manual
When operating the engine at low speed for
long periods of time, race the engine once
every two hours. Race the engine with the
clutch in NEUTRAL, accelerate from the low
speed position to the high speed position
and repeat this process about five times.
This cleans out carbon from the cylinders
and the fuel injection valves.
NOTICE: Neglecting to race the engine
will result in poor exhaust color and
reduce engine performance.
Periodically operate the engine near
maximum speed while underway. This will
generate higher exhaust temperatures,
which will help clean out hard carbon
deposits, maintain engine performance and
prolong the life of the engine.
For troubleshooting assistance, see
Troubleshooting After Starting on page
59 or Troubleshooting Chart on page
61.
If necessary, see your authorized Yanmar
Marine dealer or distributor.
© 2007 Yanmar Marine International
ENGINE OPERATION
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