SUBJECT: Exhaust Leak on XQ Rental Generator Enclosure Packages

PROBLEM:

SOLUTION:

Pre-Start Inspection

This inspection should be performed before each rental.

In-Depth Inspection

1. Locate the exhaust plenum opening in the radiator housing?s roof assembly. Use a 7/16th inch wrench to remove the 1/4-20NC bolts that secure the exhaust screen to the top of the exhaust plenum opening. Set the screen and hardware aside until the necessary procedures are completed. Refer to Illustration 2.



Illustration 2.

2. Inspect the following for any paint discoloration due to heat or soot. Refer to Illustration 3.
• Exhaust plenum side of the top radiator panel
• Protective exhaust thimble



Illustration 3.

1. At the silencer connection, inspect the exhaust pipe slip joint and clamp for any discoloration due to exhaust gasses leaking past the connection area. This discoloration will appear as white streaks on the exhaust pipe (coming from the relief slots in the silencer slip cuff). Refer to Illustration 4.



Illustration 4.

2. Inspect the exhaust clamp and all exhaust mounting hardware in order to ensure that none have loosened due to temperature changes and/or vibration. The exhaust clamp should have dual nuts on each side and should be tightened to 34 Nm (25 lb ft. Refer to Illustration 4.

 

3. Inspect the 3/8-inch muffler mounting bolts in order to insure that they are torqued to 47 Nm (35 lb ft). For bolt location, refer to Illustration 5.

 

Illustration 5.

4. Inspect the plenum area. Remove any loose debris and unexpected fluids (i.e. diesel fuel or motor oil).
5. If any of the above-mentioned conditions exist, proceed with the necessary Exhaust Maintenance listed later in this TIB. DO NOT operate the machine if any of these conditions exist until maintenance has been performed.
6. If none of the above-listed conditions exist, replace the exhaust screen and continue operation of the generator set according to the Operation and Maintenance Manual.

 

Exhaust Maintenance

If any of the above-listed conditions are detected during the Pre-Start or In-Depth Inspections, perform the following procedures prior to any further operation of the generator set package.

1. Lockout and secure the generator set from inadvertent operation.
2. Remove the lower half of the exhaust hanger assembly. Set aside the lower half of the exhaust hanger assembly. Refer to Illustration 6.



Illustration 6.

3. Remove the hardware and gasket that connect the exhaust pipe assembly to the turbo outlet elbow. Refer to Illustration 7.



Illustration 7.

4. Remove the exhaust clamp that is located where the exhaust pipe connects to the exhaust silencer. Refer to Illustration 8.



Illustration 8.

5. From inside the engine compartment, remove the exhaust pipe assembly from the generator package. Refer to Illustration 9.



Illustration 9.

6. Visually inspect the following for any damage or wear. Replace any of the following components that are cracked or deformed.
• Exhaust pipe assembly
• Exhaust gasket
• Exhaust clamp
7. Use abrasive cloth to clean all sealer, oxidation, and soot from the silencer end of the exhaust pipe and the inside of the inlet pipe cuff.
8. Apply a 6mm (.25 inch) bead of Permatex MTK-1 Tail Pipe Sealer around the outer perimeter of the exhaust pipe assembly. Refer to Illustration 10.

 



Illustration 10.

9. Reinstall the exhaust pipe assembly into the generator set package. Ensure that the exhaust pipe seats completely into the silencer inlet cuff.

10. Install the exhaust clamp where the exhaust pipe and the silencer connect. Tighten the exhaust clamp to 34 Nm (25 lb ft). Make sure to use two 3/8 inch nuts on each leg of the clamp. Note: Always tighten the exhaust clamp connection before connecting the exhaust pipe assembly to the turbo outlet flange. This will eliminate the dislodging of the exhaust pipe from its seating in the silencer cuff during the following steps.

11. Use the gasket and 1/2 inch hardware to reconnect the exhaust pipe assembly to the turbo outlet elbow. Replace the exhaust gasket if any defects are observed before installation. Tighten the turbo outlet hardware to 102 Nm (75 lb ft).

12. Reinstall the lower half of the exhaust hanger assembly. For proper alignment of the exhaust system, some adjustment on the threaded hanger may be required.

13. Replace the exhaust screen that was removed in Step 1 of the "In-Depth Inspection" procedure. Note: For proper operation, ensure that the silencer rain cap aligns correctly with the opening in the exhaust screen.

14. Test the generator set for proper operation. Inspect for any indication of reoccurring exhaust leaks.

15. If no leaks are detected, operate the generator set according to the Operation and Maintenance Manual.

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