Blue Bird VISION 2011 Driver'S Handbook Manual Download

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r o u t i n e

o p e r a t i o n

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 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 filter, the driver is notified in several stages by visual

and audible alerts.

The alert system is designed to provide reasonable and comfort-

able fore-warning and adequate opportunity for the needed regeneration. As the
need for regeneration becomes more severe, the alerts become increasingly impera-
tive; 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 highly filtering engine exhaust in order to reduce

emissions, and of purging the exhaust system of accumulated exhaust 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.

[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.