Engine Timing Chain - Rattle on Start-Up

90oldsmobile11 TIMING CHAIN RATTLE TYPE NOISE FROM ENGINE SUBJECT


ON START UP-(INSTALL PF1225 ENGINE OIL FILTER)


MODELS/YEARS 1987-90 CUTLASS CALAIS AND CUTLASS SUPREME
WITH 2.3L (VIN A AND D)
NUMBER: 90-T-156

CORP.REF.NO: 076102

DATE: August 1990

SECTION: 6
Some owners of 1987-90 Cutlass Calais and Cutlass Supreme models equipped wfth a 2.3L engine may comment about a rattle type noise from the engine when the vehicle is first started. This noise will usually disappear within a few seconds.

This condition may be the result of oil, from the engine oil filter draining back into the crankcase after the engine has been shut off. As a result, engine oil pressure sufficient to fully extend the timing chain tensioner plunger, (which properly tensions the timing chain) may be delayed a few seconds when the engine is started. While there is no adverse affect on component durability or performance, timing chain noise may occur for this brief period of time.

To minimize oil filter drain back and timing chain start up rattle noise, it is recommended that an AC Type, PF1225 oil filter be installed. This filter exhibits excellent anti-drainback characteristics and is now being used in production. The PF1225 is also the recommended service replacement oil filter for this engine.