freightliner CL112 2015, Maintenance Manual

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49–00 Safety Precautions
Safety Precautions in this section apply to all
procedures within this group.
DANGER
When working on the vehicle, shut down the en-
gine, set the parking brake, and chock the tires.
Before working under the vehicle, always place
jack stands under the frame rails to ensure the
vehicle cannot drop. Failure to follow these steps
could result in serious personal injury or death.
49–01 Exhaust System
Inspection (Noise
Emission Control)
In addition to inspecting the exhaust system at the
scheduled maintenance interval, inspect the exhaust
system if the noise level of the vehicle has in-
creased. Replace parts that show leakage, wear, or
damage, with genuine Freightliner parts.
Pre-EPA07 Exhaust System
Inspecting
1. On all vehicles, check the condition of the muffler
body and the top stack. Check the inlet/outlet
tubes for leakage, dents, and corrosion, and
check for holes in the muffler. Replace parts as
required. Use new parts, equivalent to parts
originally installed on the vehicle. See
Group 49
of the Columbia® Workshop Manual for replace-
ment procedures.
2. Inspect the exhaust flex hose (see Fig. 1 ) for
leakage, wear, or damage. Replace with new
parts if replacement is needed.
3. Check for leakage at the V-band coupling, which
attaches the exhaust pipe to the turbocharger
exhaust outlet. See
Fig. 2 .
4. If leakage exists, tighten the nut on the V-band
coupling 85 lbf·in (940 N·cm). If leakage persists,
install a new V-band coupling.
5. Inspect the turbo outlet pipe, and replace it as
needed.
6. Check the U-bolt clamps for tightness, and
tighten as needed.
7. Check the isolator at the base of the exhaust
stack elbow(s) (see
Fig. 2 ), for cracking, dam-
age, and dry rot. Replace as needed.
8. Check for leakage at all wide-band exhaust
clamps. See
Fig. 3 .
If leakage exists, tighten the nuts 40 to 60 lbf·ft
(54 to 81 N·m). If leakage persists, inspect the
f490024a
1
2
3
06/01/93
4
1. Flex Hose
2. V-Band Coupling
3. Exhaust Pipe
4. Turbocharger Exhaust
Outlet
Fig. 1, V-Band Coupling and Flex Hose
08/25/95 f490127
1
2
3
1. Exhaust Pipe
2. Exhaust Elbow Isolator
3. Mounting Nut
Fig. 2, Exhaust Elbow Isolator
Exhaust
49
Columbia Maintenance Manual, September 2015
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