Without RPO NC1 or NF7
Exhaust Manifold Installation -Left (W/O RPO NC1 or NF7)Notice: Refer to Fastener Notice in Service Precautions.
1. If the engine is equipped with coolant heaters, install the left side (1) heater as follows:
1.1. Place the coolant heater (1) in position on the cylinder block.
1.2. Install the coolant heater bolt.
^ Tighten the coolant heater bolt to 10 Nm (89 inch lbs.).
2. With the manifold still on the bench, position a new manifold gasket (1) in place on the manifold sealing surface.
3. Install 2 outer manifold bolts (6) in the manifold to retain the gasket.
4. Install a new manifold to intermediate pipe flange gasket (5).
5. Using 2 hands, place the manifold (2) in the intermediate pipe and onto the cylinder head.
6. Install new manifold flange bolts (3) for maximum joint integrity. Hand tighten. Do not torque the flange bolts to specification until the engine is mounted in the vehicle.
7. Hand tighten the 2 outer manifold bolts.
8. Install the remaining manifold bolts.
^ Tighten the exhaust manifold bolts (6) to 25 Nm (18 ft. lbs.).
9. Coat the oxygen sensor threads with high temperature anti-seize, GM P/N 1237795:3 or equivalent.
10. Install the oxygen sensor (1).
^ Tighten the oxygen sensor to 40 Nm (30 ft. lbs.)