freightliner PE116DC, Maintenance Manual

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Vehicles domiciled outside of the U.S. and Canada
may not have aftertreatment equipment, depending
upon local statutory emissions guidelines.
IMPORTANT: The aftertreatment device (ATD),
which is part of the aftertreatment system (ATS),
requires special attention during regularly
scheduled maintenance inspections. No leaks
are allowed anywhere in the system. If any dis-
crepancies are discovered, refer to the engine
manufacturer’s service literature for repair in-
structions.
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.
3. If present, check the condition of the insulation
material around the exhaust pipe between the
turbocharger and the ATD.
4. On 2V2 installations, check the ATD mounting
bands for tightness. Tighten to 30 lbf·ft (41 N·m)
if needed. Do not overtighten.
NOTE: For 1-Box ATD, you will need to remove
the heat shield in order to access the DPF.
5. Check for leaks around the clamps that attach
the ATD in the ATS, and around the clamps that
retain the DPF in the ATD.
6. Check all sensors attached to the ATS for leaks
or damaged wires. No leaks are allowed. See
Fig. 1 , Fig. 2 , or Fig. 3 for Detroit Diesel ATS
sensor locations.
7. Check the DPF exterior surface for dents or
other damage. A dent over 3 inches (76 mm) in
diameter and 1/4-inch (6-mm) deep could cause
internal damage to the DPF, causing it to
malfunction.
8. Check the SCR catalyst for dents and other
damage.
9. Check for heat discoloration on the surface of
the ATD. Heat discoloration may indicate internal
damage; especially around the DPF.
NOTE: Diesel exhaust fluid creeps, causing
white crystals to form around the line fittings.
The presence of crystals does not mean the
system has a leak. Replacing fittings or trouble-
shooting components is not necessary unless
there is a system failure or a fault code.
10. Check the DEF tank, pump, metering unit, and
lines for leaks. See Section 49.02 of the New
Cascadia ™ Workshop Manual for repair proce-
dures.
11. Check any wires, lines, or hoses within 4 inches
(10 cm) of the exhaust system for heat damage.
Repair or reroute as needed.
Diesel Exhaust Fluid (DEF) Filter
Replacement
The Environmental Protection Agency’s 2010 and
later regulations require lower nitrogen oxide (NOx)
exhaust emissions. Selective catalytic reduction
(SCR) uses diesel exhaust fluid (DEF) to lower NOx
emissions in the vehicle exhaust. A filter in the DEF
pump prevents clogging of the DEF metering unit
injection nozzle.
See the engine manufacturer’s maintenance manual
for filter replacement instructions and maintenance
intervals.
Exhaust
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