INSTALLATION OF TIMING INDICATOR/SET

MODELS: 1985-89 S/T/M TRUCK W/2.5L

When completing the assembly of a 2.5L partial engine, please be aware of the following:

1) 1985 and 1986 2.5L truck engines -

The side-mounted timing indicator and plate assembly with attaching studs, as shovin in Figure 1, should simply be transferred to the new partial engine.

2) 1987 through 1989 2.5L truck engines -

The set screw, as shown in Figure 2, needs to be removed from the partial engine assembly. Apply Loctite 242 (P/N 12345382) or equivalent to the set screw and reinsert into the block. The set screw should be seated flush to the boss surface. This step is required for two reasons:

A. The set screw is loosely threaded into the partial engine block as shipped from GMSPO.

B. The threaded hole breaks out into the coolant jacket and requires application of a sealant to the set screw to prevent a coolant leak.

This step must also precede installation of the air conditioning compressor support, as shown in Figure 2, if so equipped.

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.