Mercedes-Benz Conecto, Manual

Page: 50 / 268

Operation
Replacing the fuel filter
Replacing the fuel filter
The fuel filter should be replaced before
the onset of winter when diesel fuels
with a high water content are used. This
avoids the possibility of the fuel filter
icing up.
Addition of petrol
It is not permitted to add petrol as a
flow improver for three reasons:
Buses with unit pumps could be dam-
aged from lack of lubricant when
petrol is added.
The addition of petrol changes the
hazard category for combustible li-
quids from A III for diesel fuel to A I
for petrols. This increases the risk of
explosion.
Petrol has an unfavourable effect
upon the starting behaviour of a dies-
el engine, which may result in con-
siderable starting problems at cold
temperatures.
Danger.
Risk of fire and explosion. Petrol must
never be mixed with diesel fuel.
Addition of flow improvers
In the case of winter-grade diesel fuels
with an operating reliability of -20 °C
and below, the addition of a flow im-
prover does not promote any further
improvement in low-temperature charac-
teristics because these fuels are already
saturated with flow improvers.
The following must be taken into account
when flow improvers are used:
Summer diesel fuel: should be added
when the fuel temperature is at least
+8 °C.
Winter diesel fuel: should be added
when the fuel temperature is at least
0 °C.
Since diesel fuels vary in their prop-
erties, it cannot be guaranteed that
every diesel fuel will react positively
to the addition of flow improvers. In
the case of particularly cold-resist-
ant winter-grade diesel fuels, there
could even be a deterioration in low-
temperature characteristics. The sub-
sequent addition of flow improvers is
not recommended in this instance.
40
CONECTO (C628.3--)/08.2007 GB