Lowest Vacuum Pressure Standard - Yamaha 2CMH Rigging Manual

FUEL SYSTEM VACUUM PRESSURE STANDARD

LOWEST VACUUM PRESSURE STANDARD

The lowest vacuum pressure must be fulfilled as below at an atmospheric temperature of 20°C
(68°F) and higher.
Idle: 0 kPa to –10.7 kPa (–80 mmHg)
WOT: –10.7 kPa (–80 mmHg) to –20 kPa (–150 mmHg)
* Be sure to measure the vacuum pressure which is within specification at the idle and the wide-open throttle,
after the breaking-in period has been completed.
Engine breaking-in operating conditions
^ 2-stroke carbureted models
^ 2-stroke electronic fuel injected models : Use a 50:1 pre-mixed fuel, and supply with oil injection.
^ HPDI models
^ 4-stroke models
Larger fuel filters installed onto a boat may lower the fuel vacuum pressure to –20.0 kPa (–15 mmHg) and
under. Therefore, follow the instructions mentioned above to rig the boat properly so that the fuel vacuum
pressure is within specification.
If the vacuum pressure does not surpass –10.7 kPa (–80 mmHg) at wide-open throttle, use a clear hose to
check fuel for air bubbles mixed.
: 10 hours
: Use a 25:1 pre-mixed fuel.
: Use straight gasoline (only supply with oil injection)
: Use straight gasoline.
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