Exhaust Manifold

REMOVAL & INSTALLATION

NOTE: On turbocharged engines, the turbocharger and exhaust manifold are removed as a unit. For exhaust manifold removal on engines so equipped, please refer to the Turbocharger Removal and Installation procedure which follows later in this section.

1. On carbureted engines, disconnect the hot air duct from the exhaust manifold insulator assembly (heat stove).
2. Disconnect the secondary air pipe assembly at the exhaust manifold, and position the pipes out of the way.
3. Disconnect the oxygen sensor's electrical lead. Unscrew and remove the sensor, if necessary.

   Fig. 1: Disconnect the secondary air pipe at the exhaust manifold

   Fig. 2: Remove the bolt which fastens the secondary air pipes to the rocker arm cover

   Fig. 3: Move the secondary air pipe assembly out of the way

   NOTE: If both the manifold and sensor are to be re-used, the oxygen sensor need not be removed.

4. Remove the insulator assembly from the exhaust manifold.
5. Remove the exhaust pipe or front catalytic converter attaching nuts, then disconnect the exhaust pipe or converter.
6. Unfasten the exhaust manifold attaching nuts, then remove the manifold and gaskets.

   Fig. 4: Remove the bolt which fastens the insulator assembly to the exhaust manifold

   Fig. 5: Unscrew the secondary air pipe fitting from the exhaust manifold

   Fig. 6: Lift off the insulator

7. Check the manifold for distortion with a metal straight edge and a feeler gauge as described under Cylinder Head Overhaul. Repair or replace as necessary.

   To install:

8. Position new gasket(s) and the manifold over the mounting studs. Torque the nuts to specification in several stages, working from the center outwards.
9. Connect and fasten the exhaust pipe/front catalytic converter to the manifold, using a new gasket.
10. Position and fasten the insulator assembly over the manifold. Install the fitting for the secondary air pipe assembly.

    Fig. 7: Remove the nuts which secure the front catalytic converter or exhaust pipe to the exhaust manifold

    Fig. 8: Remove the nuts which fasten the exhaust manifold to the cylinder head

    Fig. 9: Withdraw the exhaust manifold from its mounting studs

    Fig. 10: Remove the exhaust manifold gasket

11. Coat the threads with anti-seize compound and install the oxygen sensor, if applicable. Reconnect the electrical lead.
12. Position the secondary air pipe assembly and connect it to the manifold fitting. Fasten any retaining brackets or clamps.
13. On carbureted engines, connect the hot air duct to the insulator assembly.