- On-highway Truck Engine:
- C15 (S/N: BXS1-UP)
Description of Change: An improved locknut is now used on the turbocharger mounting stud of the above listed On-highway Truck Engines. The use of a former locknut resulted in reports of exhaust leaks, loss of power, and broken mounting studs. Proper torque tightening of the new locknut with a new mounting stud will eliminate stretched turbocharger mounting studs and cracked turbocharger mounting studs.
Adaptable To: A flanged hex Spiralock 168-7800 Locknut is now used on the stainless steel 238-4665 Taperlock Stud that secures the turbocharger to the exhaust manifold. When the 168-7800 Locknut is assembled with a new 238-4665 Taperlock Stud, the assembly should be torqued to 55 ± 5 N·m (41 ± 4 lb ft). The 168-7800 Locknut is effective with the (S/N: BXS1-UP) On-highway Truck Engines. Broken studs and stretched studs were reported by product support when the previous 2N-2766 Locknut was torqued onto the stud.
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| Illustration 1 | g01054399 |
The Spiralock 168-7800 Locknut (1) has a partial flat top surface without any pressed inward stake marks around the top corners of the nut. The previous 2N-2766 Locknut (2) has a top surface that is rounded with pressed stake marks around the corners of the nut. All four of the mounting studs and locknuts should be replaced together.