TIMING CHAIN COVER AND OIL PUMP PRESS REGULATOR VALVE P/N

VEHICLES AFFECTED: 1987 'A', 'C', 'E', AND 'H' MODELS EQUIPPED WITH 3.0L (VIN CODE L) AND 3.8L (VIN CODE 3) ENGINES

A change was made in the timing chain cover and oil pump pressure regulator valve on the above engines at the start of 1987 production. The new valve and cover differ from past models and the two are not interchangeable. See illustration.

Use of the new valve in the old cover will produce abnormally high oil pressures and possible oil leaks. Use of the old valve in the new cover will result in loss of oil pressure, and the oil pressure light will come on. However, the new valve and cover together can be used on past model applications.

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.