This bulletin applies to BMW 2, 3, 4 and 5 series vehicles with turbocharged B46/48 engines. If an oil leak is observed at the turbo oil return line connection, inspect the asbestos-free gasket. It may have been installed flipped upside down with the raised bead surface facing toward the turbo.
The asbestos-free gasket part number (P/N) 11 42 7 577 017 must be installed with the raised bead surface facing toward the oil return line. To repair the leak, replace the oil pipe outlet P/N 11 42 7 617 535, the asbestos-free gasket, and the O-ring P/N 11 42 8 604 872.
Example of correct gasket orientation with the gasket bead facing the return line. Don’t forget to also replace the O-ring.
About the Author
Information courtesy of Mitchell 1
Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.
Mike Mavrigian
Motor Age Editor
Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.