Exhaust Manifold: Service and Repair
EXHAUST MANIFOLD REMOVAL1. Raise vehicle and disconnect exhaust pipe from rear cowl side.exhaust manifold at articulated joint.
Fig. 18 Separate Articulated Joint, Disconnect Oxygen Sensor Wire:
2. Disconnect Oxygen Sensor lead wire at the rear exhaust manifold.
Fig. 19 Crossover Pipe:
3. Remove bolts attaching cross-over pipe to manifold.
4. Remove nuts attaching rear manifold to cylinder head and remove manifold.
5. Lower vehicle and remove screws attaching front heat shield to front manifold.
6. Remove bolts fastening crossover pipe to front exhaust manifold and nuts fastening manifold to cylinder head. Remove assemblies.
INSPECTION
Fig. 20 Check Exhaust Manifold Mounting Surface:
Inspect exhaust manifolds for damage or cracks and check distortion of the cylinder head mounting surface and exhaust crossover mounting surface with a straightedge and thickness gauge.
INSTALLATION
Fig. 21 Identify Exhaust Manifold Gaskets:
NOTE: Install the gaskets with the numbers 1-3-5 embossed on the top on the rear bank and those with numbers 2-4-6 on the front, Radiator side, bank.
1. Install rear exhaust manifold and tighten attaching nuts to 20 Nm (175 in. lbs.).
2. Attach exhaust pipe to exhaust manifold and tighten shoulder bolt to 28 Nm (250 in. lbs.).
3. Attach crossover pipe to exhaust manifold and tighten bolt to 69 Nm 51 ft. lbs.).
4. Connect heated oxygen sensor lead.
5. Install front exhaust manifold and attach exhaust crossover.
6. Install front manifold heat shield and tighten attaching screws to 15 Nm (130 in. lbs.).