freightliner CL112 2015, Maintenance Manual

Page: 158 / 180

sealclamps. If necessary, install a new wide-band
exhaust clamp.
EPA07 Exhaust System
Inspecting
IMPORTANT: The Environmental Protection
Agency’s 2007 regulations require lower ex-
haust emissions, thus requiring new exhaust
system components. See
Fig. 4 . In particular
the after-treatment device (ATD), which is part
of the after-treatment system (ATS), requires
special attention during regularly scheduled
maintenance inspections. If any discrepancies
are discovered, refer to the engine manufactur-
er’s service literature for repair instructions.
Definitions of ATS Components
Refer to the following list of definitions of ATS com-
ponents.
•
After-Treatment System (ATS)—the entire ex-
haust system from the turbocharger to the ex-
haust stack or tail pipe.
•
After-Treatment Device (ATD)—a muffler-like
canister that houses a DPF, DOC, and sensors.
•
Diesel Particulate Filter (DPF)—a filter that col-
lects and holds particulate matter (soot and
ash).
•
Diesel Oxidation Catalyst (DOC)—oxidizes hy-
drocarbons and reduces NOx.
•
Sensors—detect temperatures and pressures in
the ATS.
Inspection
1. Check for leakage at the clamp that attaches the
exhaust pipe to the turbocharger exhaust outlet.
If leakage exists, tighten the nut on the clamp to
the required torque. If leakage persists, install a
new clamp.
2. Check the exhaust pipe, bellows, and each ex-
haust seal clamp for leakage, wear, cracks, or
damage. Replace damaged components as
needed. If leakage exists at a clamp, tighten the
nuts to the required torque. If leakage persists,
install a new exhaust seal clamp. Do not reuse
seal clamps. Once a seal clamp is loosened or
removed, it must be replaced.
NOTICE
A leak in the CGI piping, including the bellows,
will allow unfiltered air and contaminants into the
engine intake, and can cause serious engine dam-
age.
NOTE: Because the CGI bellows is covered
with a metal mesh, it is difficult to see cracks or
damage that may cause a leak.
3. On vehicles with CAT engines, inspect the CGI
bellows and piping for evidence of damage or
leakage. See
Fig. 5 . If the bellows is damaged
or leaking, replace it. See 49–02 for the replace-
ment procedure.
f490025a
05/28/93
Fig. 3, Donaldson Sealclamp Wide-Band Exhaust
Clamp
Exhaust
49
Columbia Maintenance Manual, September 2015
49/2