Perkins 904D-E28T, Руководство по эксплуатации и обслуживанию, Страница: 61 / 110

When biodiesel fuel is used, crank case oil may be
influenced. This influence is due to the chemical
composition and characteristics of biodiesel fuel,
such as density and volatility, and to chemical
contaminants that can be present in this fuel, such as
alkali and alkaline metals (sodium, potassium,
calcium, and magnesium).
• Crankcase oil fuel dilution can be higher when
biodiesel or biodiesel blends are used. This
increased level of fuel dilution when using
biodiesel or biodiesel blends is related to the
typically lower volatility of biodiesel. In cylinder
emissions control strategies utilized in many of the
industrial latest engine designs may lead to a
higher level of biodiesel concentration in the
engine oil pan. The long-term effect of biodiesel
concentration in crankcase oil is unknown.
• Perkins recommends the use of oil analysis to
check the quality of the engine oil if biodiesel fuel
is used. Ensure that the level of biodiesel in the
fuel is noted when the oil sample is taken.
Performance Related Issues with B20
Due to the lower energy content than the standard
distillate fuel B20 will cause a power loss in order of 2
to 4 percent. In addition, over time the power may
deteriorate further due to deposits in the fuel
injectors.
Biodiesel and biodiesel blends are known to cause
an increase in fuel system deposits, most significant
of which are deposits within the fuel injector.
Perkins Diesel Fuel Cleaner T400012 is most
effective in cleaning and preventing the formation of
deposits. Refer to section, Perkins Diesel Fuel
System Cleaner for more information. Therefore the
use of Perkins Diesel Fuel Cleaner is recommended
when running biodiesel blends, especially B20.
General Requirements
Biodiesel has poor oxidation stability, which can
result in long-term problems in the storage of
biodiesel. Biodiesel fuel should be used within 6
months of manufacture. Equipment should not be
stored with the B20 biodiesel blends in the fuel
system for longer than 3 months.
Due to poor oxidation stability and other potential
issues, Perkins recommends that engines with
limited operational time either do not use biodiesel
blends or, while accepting some risk, limit biodiesel
blend to a maximum of B5. Examples of applications
that should limit the use of biodiesel are the following:
Standby generator sets and certain emergency
vehicles.
For standby generator sets and emergency vehicles
that cannot avoid use of biodiesel blends fuel quality
in the engine fuel tank must be sampled and checked
monthly. Test should include acid number
(“EN14104”), oxidation stability (“EN15751”
commonly know as the Rancimant test), and
sediment (“ISO12937”). For standby generator sets
oxidation stability of biodiesel blend must be 20 hours
or more as per EN 15751. If the test shows that the
fuel has degraded, fuel tank must be drained and
engine flashed by running with the fresh high-quality
diesel fuel.
For standby generator sets and emergency vehicles
that cannot avoid use of biodiesel blends fuel quality
in the engine fuel tank must be sampled and checked
monthly. Test should include acid number
(“EN14104”), oxidation stability (“EN15751”
commonly know as the Rancimant test), and
sediment (“ISO12937”). For standby generator sets
oxidation stability of biodiesel blend must be 20 hours
or more as per “EN15751”. If the test shows that the
fuel has degraded, fuel tank must be drained and
engine flashed by running with fresh high-quality
diesel fuel.
Perkins strongly recommends that seasonally
operated engines have the fuel systems, including
fuel tanks, flashed with conventional diesel fuel
before prolonged shutdown periods. An example of
an application that should seasonally flush the fuel
system is a combine harvester.
Microbial contamination and growth can cause
corrosion in the fuel system and premature plugging
of the fuel filter. Consult your supplier of fuel for
assistance in selecting appropriate antimicrobial
additive.
Water accelerates microbial contamination and
growth. When biodiesel is compared to distillate
fuels, water is naturally more likely to exist in the
biodiesel. Frequent checks are therefore essential
and if necessary, drain the water separator.
Materials such as brass, bronze, copper, led, tin, and
zinc accelerate the oxidation process of the biodiesel
fuel. The oxidation process can cause deposits
formation therefore these materials must not be used
for fuel tanks and fuel lines.
Fuel for Cold-Weather Operation
The European standard “EN590” contains climate
dependant requirements and a range of options. The
options can be applied differently in each country.
There are five classes that are given to arctic
climates and severe winter climates. 0, 1, 2, 3 and 4.
Fuel that complies with “EN590” CLASS 4 can be
used at temperatures as low as −44 °C (−47.2 °F).
Refer to “EN590” fora detailed discretion of the
physical properties of the fuel.
M0108133-04 61
Maintenance Section
General Fuel Information