Diesel Engine - Turbo Induced Exhaust Drone/Moan
Article No.04-9-4
05/11/04
^ ENGINE - EXHAUST - TURBO-INDUCED EXHAUST
MOAN/DRONE AT 1600-1800 RPM - 6.0L BUILT
PRIOR TO 9/29/2003
^ NOISE - VIBRATION - TURBO-INDUCED EXHAUST
MOAN/DRONE AT 1600-1800 RPM - 6.0L BUILT
PRIOR TO 9/29/2003
FORD:
2003-2004 EXCURSION, F SUPER DUTY
ISSUE
Some 2003-2004 Super Duty F-Series and Excursion vehicles built before 9/29/2003 with a 6.0L engine may exhibit a turbo-induced exhaust moan/drone between 1600-1800 RPM.
ACTION
To service, neutralize the exhaust system. It may also be necessary to install a revised turbocharger pedestal mounting bracket if it is not already installed. Refer to the following Service Procedure.
SERVICE PROCEDURE
1. Inspect exhaust system, confirm hangers and isolators are properly positioned. Correct any bent or damaged hangers and/or bound up isolators.
2. Loosen turbocharger exhaust down pipe (6N646) at the V-band clamp and connecting flange at the catalyst inlet pipe.
3. Confirm proper turbocharger downpipe alignment to catalyst inlet pipe. With turbo downpipe in a neutralized position retighten turbo downpipe V-bland clamp at turbo and connecting flange at catalyst.
4. Re-evaluate for exhaust/turbo moan. If condition is corrected return the vehicle to customer. If not corrected, proceed to step 5.
5. Remove turbocharger and turbocharger pedestal mounting bracket per Workshop Manual Section 303 to verify part number on mounting bracket.
a. If part number on the bracket is 1846207C1, perform REASSEMBLY OF TURBOCHARGER AND MOUNTING PEDESTAL, AND NEUTRALIZE EXHAUST below before performing final torque procedure of pedestal to block and reinstalling/refastening turbocharger.
b. If part number on the bracket is not 1846207C1, replace the turbocharger pedestal mounting bracket with service part number 3C3Z-6N639-BA. Perform REASSEMBLY OF TURBOCHARGER AND MOUNTING PEDESTAL, AND NEUTRALIZE EXHAUST below before performing final torque procedure of pedestal to block and reinstalling/refastening turbocharger.
REASSEMBLY OF TURBOCHARGER AND MOUNTING PEDESTAL, AND NEUTRALIZE EXHAUST
NOTE
PROPER ASSEMBLY AND TORQUE SEQUENCE OF THE TURBO LEFT HAND SIDE (LHS) Y-PIPE (6K854) AND RIGHT HAND SIDE (RHS) STRAIGHT-PIPE (6K854) CONNECTIONS, TO TURBO, EGR COOLER, AND EXHAUST MANIFOLDS, IS CRITICAL TO ENSURE THE DURABILITY OF THE EXHAUST PIPE FLEX BELLOWS, AND MINIMIZE TURBO INDUCED EXHAUST MOAN/DRONE NOISE.
NOTE
APPLY HIGH TEMPERATURE NICKEL ANTI-SEIZE LUBRICANT (F6AZ-9L494-AA) TO BOLT THREADS PRIOR TO REASSEMBLY.
1. Loosen the V-band clamp at the EGR cooler.
NOTE
DO NOT REMOVE METAL GASKET BETWEEN THE EGR COOLER AND THE UP-PIPE.
2. Loosen the M8 bolts at the intermediate flat flanges connecting the exhaust Y-pipe to the RHS exhaust straight pipe.
NOTE
DO NOT REMOVE METAL GASKET BETWEEN THE RHS EXHAUST STRAIGHT PIPE AND Y-PIPE FLANGES.
3. Loosen the two M8 bolts securing the RHS straight pipe to the RHS exhaust manifold.
4. Loosen the M8 bolts at the LHS Y-pipe to the LHS exhaust manifold.
5. Reposition the Y-pipe and straight pipe lower legs from the exhaust manifolds to provide a straight inner and outer pipe alignment through the flex bellows and eliminate any distortion in the bellows.
6. Using hand tools snug the flat flange fasteners between the Y-pipe and straight pipe.
7. Re-secure with the V-band clamp at the EGR cooler. Final torque to 6 N.m (53 lb-in).
NOTE
BEFORE FINAL TORQUE OF TURBO PEDESTAL FASTENERS, PLACE TURBOCHARGER ONTO MOUNTING PEDESTAL AND CHECK Y-PIPE FLANGE TO TURBO FLANGE MATING ALIGNMENT. IF NOT ALIGNED, REPOSITION TURBO AND PEDESTAL FOR PROPER FLUSH ALIGNMENT TO MATING Y-PIPE FLANGE.
8. Final torque pedestal fasteners to 31 N.m (23 lb-ft).
9. Complete turbocharger installation, final torque turbo mounting fasteners per Workshop Manual Section 303 instructions.
10. Re-secure LHS Y-pipe V-band clamp at the turbo. Final torque to 12 N.m (9 lb.ft).
11. Check for good alignment and fit of the lower LHS Y-pipe and RHS straight pipe flanges at the mating exhaust manifold outlets. Secure the LHS Y-pipe and RHS straight pipe to the exhaust manifold outlets using M8 bolts (two (2) per side). Using hand tools snug fasteners evenly to position the pipe flanges square to the pipe and parallel to the exhaust manifold flanges. There should be an equal gap spacing between the pipe flange and exhaust manifold flange at both the top and bottom bolts (Figure 1).
12. Final torque LHS Y-pipe to RHS straight pipe flat flange fasteners to 27 N.m (20 lb-ft).
13. Final torque LHS Y-pipe and RHS straight pipe exhaust manifold flange fasteners to 27 N.m (20 lb-ft).
14. Re-secure exhaust down pipe V-band clamp and final torque to 10 N.m (89 lb-in).
15. After complete reassembly, road test vehicle to confirm no exhaust leaks and exhaust moan condition is resolved.
Parts Block
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
OPERATION DESCRIPTION TIME
040904A Inspect Exhaust (Includes 1.2 Hrs.
Time To Neutralize And
Adjust Exhaust If
Necessary) Perform Road
Test To Re-Evaluate If
Noise Is Corrected
040904B Inspect Exhaust (Includes 3.6 Hrs.
Time To Neutralize And
Adjust Exhaust If
Necessary) Perform Road
Test To Re-Evaluate Noise
Is Still Present Verify
Correct Turbocharger
Pedestal Replace It
Necessary (Includes Time
To Remove And Install
Turbocharger)
DEALER CODING
CONDITION
BASIC PART NO. CODE
6N639 42
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