OIL CONTAMINATION ON TURBO CHARGED ENGINE

1.8L AND 2.0L OHC TURBO - OIL CONTAMINATION

1984-88 L-4 TURBO 1.8L (VIN J) AND 2.0L (VIN M) ENGINES IN SUNBIRD AND GRAND AM VEHICLES

The cleanliness of oil in a turbo application is extremely important, as implied by the "more frequently" change interval status in the owner's manual. Any "built-up" oil contamination in the lubricating system should be eliminated. That is why the service manual procedure (Section 6J-4, regarding oil change with a turbo replacement) should be followed.

An often overlooked source of contamination is the turbo oil feed and return lines. A new turbo's bearings can be quickly destroyed by any line contamination.

Before installing a new turbo, both the feed and return oil lines should be checked visually for contamination and by probing with a length of wire. If contamination is suspected, replace the suspect line.

Use applicable service labor code and labor time.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.