Exhaust manifolds — removal and installation

Removal

Warning: Use caution when working around the exhaust manifolds, the sheet metal heat shields can be sharp on the edges. Also, the engine should be cold when this procedure is followed.

1. Disconnect the cable from the negative terminal of the battery (see Engine electrical systems).

2. Raise the vehicle and support it securely on jack stands.

3. If you’re removing the left side manifold, use a dab of paint to mark the alignment of the upper section of the steering intermediate shaft to the lower part of the steering column. Remove the fasteners, then separate the shafts so they can be moved aside (see Suspension and steering).

Caution: Don’t move the wheels or the steering wheel after disconnecting the shafts. The airbag system clock spring could be damaged.

4. Working under the vehicle, apply penetrating oil to the exhaust pipe-to-manifold studs and nuts (they’re usually rusty).

5. Remove the nuts retaining the exhaust pipe (s) to the manifold(s) (see illustration).

8.5 Access the exhaust pipe bolts/nuts from underneath the vehicle — on some models it may be easier to remove the wheel and work through the fender well opening

Chevrolet Silverado V6 engine 4,3L _ Access the exhaust pipe bolts/nuts from underneath the vehicle - on some models it may be easier to remove the wheel and work through the fender well opening

6. Refer to Chapter Tune-up and routine maintenance and disconnect the spark plug wires.

7. Remove the exhaust manifold fasteners (see illustration).

8.7 Exhaust manifold mounting bolts (heat shield removed for clarity) — right side shown, left side similar

Chevrolet Silverado V6 engine 4,3L _ Exhaust manifold mounting bolts (heat shield removed for clarity) - right side shown, left side similar

8. Remove the manifolds along with the heat shields. Throw the gaskets away. The heat shields can be removed at this time.

Installation

9. Check the manifold for cracks and make sure the bolt threads are clean and undamaged. The manifold and cylinder head mating surfaces must be clean before the manifolds are reinstalled — use a gasket scraper to remove all carbon deposits.

10. Position the manifold on a bench and install the heat shields, bolts and gaskets onto the manifold. Retaining tabs surrounding the gasket bolt holes will hold the assembly together as the manifold is installed. Place the manifold on the cylinder head and install the mounting bolts finger tight.

11. When tightening the mounting bolts, work from the center to the ends and be sure to use a torque wrench. Tighten the bolts in two steps to the torque listed in this Chapter’s Specifications. If equipped, bend the locking tabs back against the bolt heads.

12. The remainder of installation is the reverse of removal.

13. Start the engine and check for exhaust leaks.

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