Volvo D11 series, Installation Manual

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66
Fuel system
General
Installation of the fuel system components - fuel
tanks, cocks, fuel piping and extra fuel filters, etc.,
must be carried out very carefully to assure the en-
gine has a sufficient supply of fuel and that demands
concerning perfect sealing and fire safety are satis-
fied.
Plan the location of the tanks very carefully before
starting work. Use good quality cocks to avoid fuel
leakage. A leaking fuel system always implies a great
risk of operational disturbances and the danger of fire.
Utilize high grade material and high quality compo-
nents.
The cocks should preferably be fitted outside the en-
gine room or be remote controlled.
The amount of fuel can be subdivided between sev-
eral tanks to keep the centre of gravity low and also
provide certain trimming possibilities for the hull.
If the tanks are built in, the surrounding space should
be provided with ventilation.
NOTE! Local legislation may apply which in all over-
ride the engine manufacturers literature and recom-
mendations.
Be sure not to bend the high pressure pipes between
injection pump and injectors and do not stand on
the engine due to risk of bending the high pressure
pipes.
Do not clamp anything to the high pressure pipes,
and keep the original clamping intact on the engine.
Otherwise there will be a risk of broken pressure line
and fire.
When working with the fuel system it is important to
keep it free from dirt.
Fuel tanks
If possible, the tanks should be located so that they
are at the same level or somewhat higher than the
engine. If they are placed lower, due attention must
be paid to the maximum suction height of the feed
pump which is .5 m (4’9") for D5/D7 and 2 m (4’9")
for all other engines. Note that the suction height
must be calculated from the lower end of the suction
pipe, i.e. 25 mm (") above the bottom of the tank.
The return pipe should be installed about 0 mm
(0.4") above the tank bottom and minimum 300 mm
away from the suction pipe, to prevent air from enter-
ing when the engine is switched off.
If the tanks are located lower than the level permitted
by the suction height of the fuel feed pump, then the
fuel is to be pumped up to a day tank by means of a
hand pump or power pump. Return fuel from the en-
gine is taken in this case to the day tank.
Shut-off valves should be fitted on the fuel and return
line, if the fuel tank's maximum level is higher than
2.5 m (8'3") for D5/D7 above the injection pump of
the engine . For D9/D/D2/D6 engines it must not
be higher than the cylinder head of the engine.
The valves should be shut off during permanent en-
gine stop. There is otherwise a risk that fuel may leak
through the injection pump to the lubricating system.