Paccar Kenworth T680 2019, Manual

Page: 18 / 194

2-6
Section 2
Safety & Compliance
2/17
Exhaust and Exhaust After-treatment System
The following are highlights of some of the more common or critical aspects of this system.
• The following after-treatment and exhaust system components may not be modified:
• DPF assembly
• SCR Catalyst assembly
• Exhaust pipes between the engine and after-treatment devices (DPF, SCR Catalyst) and between
after-treatment devices
• NO
x
Sensors
• PM Sensor
• The following modifications may only be done within the guidelines of the “DEF System Relocation Guide.”
• Modifications to Diesel Exhaust Fluid (DEF) throttle, suction, or pressure lines
• Modification or relocation of the DEF tank
• Modification of coolant lines to and from the DEF tank
• All DEF and coolant lines should be routed, protected, and properly secured to prevent damage during vehicle
operation or other components
• If relocation of the DCU or ACM is necessary, use existing frame brackets and mount inside of frame flanges
where necessary. Do not extend the harnesses
• The DPF, the SCR catalyst, or their mounting may not be modified
• The NOx sensor may not be relocated or altered in any way; this includes re-clocking the aftertreatement
canister or reorienting the sensor(s)
• Exhaust pipes used for tailpipes/stacks must be properly sized, and must prevent water from entering
• Ensure adequate clearance between the exhaust and body panels, hoses, and wire harnesses
• The body in the vicinity of the DPF must be able to withstand temperatures up to 400°C (750°F)
• Do not add thermal insulation to the external surface of the DPF
• The SCR water drain hole may not be blocked
• Allow adequate clearance (25mm (1 inch)) for servicing the DPF sensors, wiring, and clamped joints
• Drainage may not come in contact with the DPF, SCR catalyst, sensors or wiring
• Allow sufficient clearance for removing sensors from DPF. Thermistors require four inches. Other sensors
require one inch
• Wiring should be routed, protected from heat, and properly secured to prevent damage from
other components
• The exhaust system from an auxiliary power unit (APU) must not be connected to any part of the vehicle
after-treatment system or vehicle tail pipe.
Cooling System
The following are highlights of some of the more common or critical aspects of this system.
• Modifications to the design or locations of fill or vent lines, heater or defroster core, and surge tank are not
recommended
• Additional accessories plumbed into the engine cooling system are not permitted, at the risk of voiding vehicle
warranty
• Coolant level sensor tampering will void warranty