No leaks are allowed anywhere in the system. If
any discrepancies are discovered, refer to the
engine manufacturer’s service literature for re-
pair instructions.
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.
Check the ATD mounting bands for tightness.
Tighten to 30 lbf·ft (41 N·m) if needed. Do not
overtighten.
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 ATD for leaks
or damaged wires. No leaks are allowed.
7.
Check the DPF exterior surface for dents or
other damage. See Item A of
. 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.
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1
2
3
4
5
6
7
8
9
10
11
12
13
14
9
15
NOTE: The sensor box (item 8) contains the SCR inlet and outlet NOx sensors, DPF outlet pressure sensor, and the
DOC inlet pressure sensor.
1.
DOC Outlet Temperature
Sensor
2.
DOC Inlet Pressure Sensor
Port
3.
DOC Inlet Temperature Sensor
4.
Front Heat Shield
5.
DEF Nozzle
6.
Exhaust Outlet
7.
DEF Metering Unit
8.
Sensor Box (see note above)
9.
Exhaust Inlet
10. SCR Outlet Temperature
Sensor
11. SCR Outlet NOx Sensor Port
12. SCR Inlet NOx Sensor Port
13. 14-Pin Connectors
14. DPF Outlet Pressure Sensor
Port
15. SCR Inlet Temperature Sensor
Fig. 1, One-Box ATS Sensor Locations
Exhaust
49
Business Class M2 Maintenance Manual, November 2015
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