Dpf Regeneration In Blue Bird Buses - Blue Bird D3RE 2014 Driver's Handbook Manual

DPF Regeneration In Blue Bird Buses

As with most new mechanical processes, the introduction of more sophisticated ex-
haust systems in 2010 emission standards-compliant engines has generated some
degree of initial confusion. Engine manufacturers have designed their own methods
to accomplish the regeneration (cleaning) of the DPF, and therefore describe the pro-
cess in somewhat differing terms.
The Cummins equipped Blue Bird bus exhaust system is not complicated. Nor
should the regeneration process be regarded with alarm. Both Drivers and service
technicians should be at least conceptually familiar with the regeneration process.
As soot builds up in the DPF, the driver is notified in several stages by visual and
audible alerts. The alert system is designed to provide reasonable and comfortable
fore-warning and adequate opportunity for the needed regeneration. As the need
for regeneration becomes more severe, the alerts become increasingly imperative;
and the penalty for postponing the needed regeneration also increases.
When the earliest alerts occur, there is typically ample time to complete a route
and then have a Stationary Regeneration procedure performed at a proper facility. If
early alerts are ignored, and the condition is allowed to worsen, the engine will even-
tually de-rate automatically, and performance will reduce noticeably. If the condition
is allowed to become severe, a Stationary Regeneration may not be possible, and the
DPF may require removal and treatment using specialized equipment. Therefore, to
minimize disruption of your bus operation, the regeneration-related alerts should be
heeded and responded to at their early stages as a matter of routine.
Aftertreatment Terms
The following summarizes some of the terms associated with the exhaust systems of
Blue Bird buses equipped with 2010 emission standards compliant engines. Both the
driver and technician should become familiar with the following terms:
Aftertreatment. The process of catalytically converting and filtering engine exhaust
in order to reduce emissions, and of purging the exhaust system of accumulated ex-
haust residue.
DPF (Diesel Particulate Filter). A component in the exhaust system which takes the
place of a traditional muffler. A DPF contains a special dissimilar metals filter which
traps particulate accumulation (soot), which is then converted to carbon dioxide by
the aftertreatment process. The Cummins DPF also contains a catalytic converter.
Regeneration. The process of cleaning accumulated soot from the filtering compo-
nents inside the DPF. Regeneration occurs at high exhaust system temperatures to
turn the soot into carbon dioxide gas. Regeneration can be thought of as conceptu-
ally similar to the clean cycle of a self-cleaning oven.
60
DRIVER'S HANDBOOK
[WARNING] Postponing
regeneration beyond the early
indications may result in the
engine being automatically
de-rated, and reduction of power
while driving.
[WARNING] The aftertreatment
regeneration process can cause
extremely high exhaust gas tem-
peratures hot enough to ignite or
melt common materials, and to
burn people.
Carefully read, understand,
and abide by all instructions,
warnings, and cautions in the
engine manufacturer's operator's
manual (and other related
engine manufacturer's literature)
regarding safe operation when
the HEST indicator is on.
Carefully read, understand,
and abide by all instructions,
warnings, and cautions in the
engine manufacturer's operator's
manual (and other engine man-
ufacturer's literature) regarding
safety conditions when perform-
ing Stationary regeneration.