Timing Chain Cover/Oil Pump Pressure Regulator Valve

Bulletin 87-6-5

Date Dec., '86

Ref. No. 87-036-6
SUBJECT: NEW TIMING CHAIN COVER AND OIL PUMP PRESSURE REGULATOR VALVE

MODELS AFFECTED: 1987 CENTURYS, LESABRES, ELECTRAS AND RIVIERAS EQUIPPED WITH 3.0L (VIN CODE L) AND 3.8L (VIN CODE 3) ENGINES

TIMING CHAIN COVER:

SOLID VALVE:

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.