Inspection of the EPA07 Exhaust System

p3 mm 49.01.000

To meet EPA07 emissions regulations for vehicles domiciled in the USA or Canada, engines manufactured after December 31, 2006 are equipped with an emission aftertreatment system. Vehicles domiciled outside of the USA and Canada may not have aftertreatment equipment, depending upon local statutory emissions guidelines.

Note: The aftertreatment device (ATD), which is part of the aftertreatment system (ATS), requires special attention during regularly scheduled maintenance inspections; see Fig.. No leaks are allowed anywhere in the system. If any discrepancies are discovered, refer to the engine manufacturer's service literature for repair instructions.

  • Inspect this area of the canister for dents.

Fig. 1, Typical EPA07 Aftertreatment Device

  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 exhaust 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. On vehicles with CAT engines, inspect the CGI bellows and piping for evidence of damage or leakage. See Fig.. If the bellows is damaged or leaking, replace it. See 49–02 for the replacement procedure.

    1. Clamp

    2. Inlet Pipe

    3. U-Clamp

    4. Forward Pipe-Support Brace

    5. Slip Clamp

    6. CGI Bellows

    7. Center Pipe-Support Brace

    8. Center Pipe

    9. Clamp

    10. Outlet Pipe

    Fig. 2, CAT EPA07 Exhaust Installation with CGI Bellowsice

  4. If present, check the condition of the insulation material around the exhaust pipe between the turbocharger and the ATD.
  5. Check the ATD mounting bands for tightness. If needed, tighten the mounting bands on horizontally and vertically mounted ATDs to 30 lbf·ft (41 N·m); on step-mounted ATDs, tighten the mounting bands to 15 lbf·ft (20 N·m). Do not overtighten.
  6. Check for leaks around the clamps that attach the ATD in the ATS, and around the clamps that retain the DPF in the ATD.
  7. Check all sensors attached to the ATD for leaks or damaged wires. No leaks are allowed.
  8. Check the DPF exterior surface for dents or other damage. See Ref. A of Fig.. A dent over 3 inches (76 mm) in diameter or 1/4-inch (6-mm) deep could cause internal damage to the DPF, causing it to malfunction.
  9. Check for heat discoloration on the surface of the ATD. Heat discoloration may indicate internal damage; especially around the DPF.
  10. Check any wires, lines, or hoses within 4 inches (10 cm) of the exhaust system for heat damage. Repair or reroute as needed.
Note:
Parent topic: EPA07 Exhaust System
Document Number: 0000116549
Manual Publication Date: 2024-05-15
Topic Publication Date: 2024-11-22