Intake Manifold: Service and Repair

Fig. 2 Intake Manifold Bolt Tightening Sequence. 4.3L:

Fig. 3 Intake Manifold Bolt Tightening Sequence. 5.0L & 5.7L:

1. On models equipped with airbag, disable airbag system as described under MAINTENANCE PROCEDURES/AIRBAG SYSTEM DISARMING.
2. On all models, disconnect battery ground cable, drain cooling system and remove air cleaner.
3. Disconnect accelerator, transmission and cruise control linkages, as equipped.
4. Disconnect fuel line from carburetor or TBI unit and remove fuel line clips as needed, then remove carburetor or throttle body from intake manifold.
5. Disconnect necessary vacuum hoses and electrical connectors, noting position for installation.
6. Disconnect upper radiator and heater hoses from manifold.
7. On Cadillac Brougham models, remove thermostat and housing.
8. On all models, remove distributor.
9. Remove ignition coil, AIR pump, cruise control servo and brackets, as needed.
10. Remove alternator upper mounting bracket and EGR solenoids.
11. Remove manifold retaining bolts and the manifold.
12. Reverse procedure to install, noting the following:
a. Ensure surfaces are clean and dry, then apply 3/16 bead of RTV sealer on each block ridge and apply suitable sealer around water outlets, install gaskets and secure gasket position by extending bead of sealer approximately 1/2 inch onto gasket ends.
b. Install manifold and retaining bolts, ensuring areas between case ridges and manifold are completely sealed.
c. Torque manifold bolts to specifications in sequence shown in Figs. 2 and 3.
d. After installing carburetor or TBI unit, check to ensure no fuel leakage is present.
13. Rearm airbag system as described under MAINTENANCE PROCEDURES/AIRBAG SYSTEM DISARMING.