THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN NO. 89-225-6, DATED JULY 1989. THE 1990-91 MODEL YEAR HAS BEEN ADDED AS WELL AS THE PART NUMBER CORRECTED. ALL COPIES OF 89-225-6 SHOULD BE DISCARDED.
- Two styles of rocker arm cover are available, with and without dimples in the flange area.
- Both silicone/steel and cork/rubber gaskets are available for service applications.
- With the dimpled cover, the cork/rubber gasket, P/N 101 01 791 is preferred; however, RTV may be used.
- With the non-dimpled cover, the silicone/steel gasket, P/N 10124688 is preferred. However, the cork/rubber gasket may be used.
Parts are currently available from GMSPO.
Even though the gaskets are less sensitive to surface contamination, it is recommended that the sealing surfaces be as clean as possible to assure a reliable seal.
Inspect the rocker arm cover for any bent or distorted flanges. If the flanges are damaged, replace the cover with a new like part.
For the composite cork/rubber gasket, remove the protective paper from the gasket. Place the sticky side of the gasket onto the rocker arm cover.
Install the rocker arm cover onto the cylinder head and torque the cover bolts to 45 in. lb. (5 N. m).
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.