Fuel tanks should have the following features:
The ller neck should be raised so that water will not enter when lling.
The ller cap should seal effectively to prevent water entering when under way.
A vent pipe should be tted, again in such a way as to avoid the entry of water.
The tank should have a sump or angled bottom with a drain tap so that water and sediment can be
removed. (This is not always possible).
Internal bafes may be required to prevent fuel surge.
The tank should have a removable panel to simplify cleaning.
The fuel pipework should be as simple as possible with the minimum of valves and cross connections,
so that obscure fuel feed problems are minimised.
A fuel sedimenter (i.e. water trap) is required in the fuel system between the fuel tank and the engine
mounted lift pump. To avoid problems when venting air after draining the sedimenter, it should preferably
be installed below the normal minimum level of fuel in the fuel tank. (This is not always possible!).
The tank should have at least two connections; a fuel feed connection, and a fuel return connection.
Whenever possible a tank should only supply one engine, but in any case each engine should have its
own fuel pipes, from tank to engine.
6.2 Typical Fuel Systems
The more simple the fuel system, the better it will perform in service. Figure 1 shows an ideal system.
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Fuel return pipe
Stop cock
Main fuel feed Water separator
Fuel tank
Figure 1 - A Simple Fuel System.