72
SEBU8603-01
Maintenance Section
Re
fi
ll Capacities
Table 18
Acceptable Fuel Speci
fi
cation for the 1200 Series of Engines
(1)
Fuel Speci
fi
cation
Comments
EN590
European Automotive Diesel Fuel (DERV)
“ASDM D975 GRADE 1D S15”
“North American Light Distillate Diesel fuel with less than 15
PPM sulfur level”
“ASTM D975 GRADE 2D S15”
“North American Middle Distillate general purpose Diesel fuel
with less than 15 PPM sulfur level”
“JIS K2204”
“Japanese Diesel Fuel” Must meet the requirements that are
stated in the section “Lubricity”.
“BS 2869: 2010 CLASS A2 or EU equivalent ”
“EU Off Road Diesel fuel. Acceptable from 2011 MUST have
less than 10 PPM sulfur level”
(1)
All the fuels must comply with the speci
fi
cation in the table for the Perkins Speci
fi
cation Distillate Diesel Fuel.
Diesel Fuel Characteristics
Cetane Number
Fuel that has a high cetane number will give a
shorter ignition delay. A high cetane number will
produce a better ignition quality. Cetane numbers are
derived for fuels against proportions of cetane and
heptamethylnonane in the standard CFR engine.
Refer to “ISO 5165” for the test method.
Cetane numbers in excess of 45 are normally
expected from current diesel fuel. However, a cetane
number of 40 may be experienced in some territories.
The United States of America is one of the territories
that can have a low cetane value. A minimum cetane
value of 40 is required during average starting
conditions. A fuel with higher cetane number is
recommended for operations at high altitudes or in
cold-weather operations.
Fuel with a low cetane number can be the root cause
of problems during a cold start.
Viscosity
Viscosity is the property of a liquid of offering
resistance to shear or
fl
ow. Viscosity decreases
with increasing temperature. This decrease in
viscosity follows a logarithmic relationship for normal
fossil fuel. The common reference is to kinematic
viscosity. Kinematic viscosity is the quotient of the
dynamic viscosity that is divided by the density. The
determination of kinematic viscosity is normally by
readings from gravity
fl
ow viscometers at standard
temperatures. Refer to “ISO 3104” for the test
method.
The viscosity of the fuel is signi
fi
cant because fuel
serves as a lubricant for the fuel system components.
Fuel must have suf
fi
cient viscosity in order to lubricate
the fuel system in both extremely cold temperatures
and extremely hot temperatures. If the kinematic
viscosity of the fuel is lower than “1.4 cSt” at the fuel
injection pump, damage to the fuel injection pump
can occur. This damage can be excessive scuf
fi
ng
and seizure. Low viscosity may lead to dif
fi
cult hot
restarting, stalling, and loss of performance. High
viscosity may result in seizure of the pump.
Perkins recommends kinematic viscosities of 1.4 and
4.5 mm2/sec that is delivered to the fuel injection
pump. If a fuel with a low viscosity is used, cooling of
the fuel may be required to maintain 1.4 cSt or greater
viscosity at the fuel injection pump. Fuels with a high
viscosity might require fuel heaters in order to lower
the viscosity to 4.5 cSt at the fuel injection pump.
Density
Density is the mass of the fuel per unit volume
at a speci
fi
c temperature. This parameter has a
direct in
fl
uence on engine performance and a direct
in
fl
uence on emissions. This in
fl
uence determines
from a heat output given injected volume of fuel. This
parameter is quoted in the following kg/m
3
at 15 °C
(59 °F).
Perkins recommends a density of 841 kg/m
3
in order
to obtain the correct power output. Lighter fuels are
acceptable but these fuels will not produce the rated
power.
Sulfur
The level of sulfur is governed by emissions
legislations. Regional regulation, national regulations,
or international regulations can require a fuel with
a speci
fi
c sulfur limit. The sulfur content of the fuel
and the fuel quality must comply with all existing local
regulations for emissions.