Nanni Q1100 Series, User Manual

Page: 46 / 98

46
S06 STARTING & RUNNING
BEFORE STARTING
FUEL SYSTEM
Fuel is drawn from the tank by the fuel feed pump and
injected into the combustion chamber by the injection
pump. A fuel filter is placed between the fuel supply pump
and the injection pump.
The injection pump delivers more fuel than is required for
combustion. The unburned fuel is returned to the tank
through an overflow pipe.
CAUTION!
The injection pump is an extremely sophisticated device.
The entry of water into the fuel system will result in a ma-
jor failure of the injection pump and the entire fuel sys-
tem.
A fuel prefilter with a water separator must be installed
between the fuel tank and the engine fuel filter. The prefil -
ter should be installed as close as possible to the engine
fuel filter. It should never be installed on top of the engine
because vibration affects the fuel/water separation pro-
cess.
If the fuel tank is located under the engine fuel injection
pump, an additional electrical supply pump must be in-
stalled between the prefilter and the engine fuel pump.
RAW WATER
The raw water system cools the engine coolant and the
exhaust gases.
The raw water is drawn into the heat exchanger by the
engine’s raw water pump. The raw water is discharged
via the exhaust elbow, where it is mixed with the exhaust
gases.
The anti-siphon prevents raw water from entering the cyl-
inders via the raw water/exhaust system.
NOTE!
A siphon is mandatory if the exhaust elbow is below the
waterline at full load or less than 200 mm above. An an-
ti-siphon is mandatory on all sail-boats and when there is
a risk of water entering the engine.
A raw water filter must be installed between the raw water
intake and the engine raw water pump.