87. Exhaust Manifold Installation - Left

Exhaust Manifold Installation - Left





Important:
- Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or On-Board Diagnostic (OBD) II system performance.
- The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material.

Important: Do not apply sealant to the first three threads of the bolt.

1. Apply a 5 mm (0.2 inch) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488) or equivalent to the threads of the exhaust manifold bolts. Refer to Sealers, Adhesives, and Lubricants.

2. Install the exhaust manifold and NEW exhaust manifold gasket.

Notice: Refer to Fastener Notice in Service Precautions.

3. Install the exhaust manifold bolts.
3.1. Tighten the exhaust manifold bolts a first pass to 15 Nm (11 lb ft). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
3.2. Tighten the exhaust manifold bolts a final pass to 25 Nm (18 lb ft). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
4. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the left cylinder head.





5. Install the heat shield (603) and bolts (604).
Tighten the heat shield bolts to 9 Nm (80 lb in).