Blue Bird VISION 2011, Руководство водителя

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VISION
D R I V E R S H A N D B O O K
10
About 2010 Emissions Standards
Buses equipped with 2010 engines are designed to conform to new and stringent
federal emissions standards. These standards affect both the equipment installed at
the factory and the fuel at the pump.
Buses powered by 2010 emissions standards engines are equipped with special
exhaust systems to reduce emissions. The technical details of the systems employed
by various engine manufacturers differ, but share common general principles. The
exhaust muffler is replaced by a particulate filter which traps and burns microscopic
particles in a process referred to as “regeneration.” When heat in the exhaust is insuf-
ficient to fully burn the particulates, the system enters an “active” regeneration mode
so the necessary catalytic reaction can take place. During active regeneration events,
exhaust temperatures are elevated, and an indicator light on the instrument panel
illuminates to notify the Driver that regeneration is active. This regeneration mode is
automatic and normal, and requires no special action on the part of the Driver.
Removing particulate matter (soot) from the exhaust stream through regenera-
tion alone will not satisfy the more stringent 2010 emission standard. This standard
requires reduced levels of Nitrogen Oxide (NOx). To achieve this a Selective Catalytic
Reduction system (SCR) is added downstream to the diesel particulat filter. The SCR
system uses a chemical reactant – in this case Diesel Exhaust Fluid (DEF) – which
converts to ammonia in the exhaust stream and reacts with NOx to form harmless
nitrogen gas and water.
As part of the 2007 emissions standards, effective October 15, 2006, the EPA has
required fuel retailers to sell lower-emission fuel, designated “ultra-low-sulfer diesel”.
After that date, all commercially-available number 1 and number 2 highway diesel
fuels are Ultra-low-sulfer diesel. This fuel must be used in all 2011 model buses pow-
ered by a diesel engine, as indicated by a decal located near the fuel filler door, read-
ing:
The engine in this vehicle must be operated only with low ash engine oil and
ultra low sulfur diesel fuel (meeting EPA specifications for highway diesel fuel,
including a 15 ppm sulfur cap).
For detailed information on recommended fuels and other fluids, always follow your
engine manufacturer’s guidlines.