REMOVAL & INSTALLATION
See Figures 1 and 2
Be sure to keep all the components in the exact order of removal so they may be installed in there original location; adjust the valve lash after replacing the rocker arms. Coat the replacement rocker arm and ball with engine oil before installation.
Rocker arms studs that have damaged threads or are loose in the cylinder heads may be replaced by reaming the bore and installing oversize studs. Oversizes available are 0.003 in. (0.076mm) and 0.013 in (0.33mm). The bore may also be tapped and screw-in studs installed. Several aftermarket companies produce complete rocker arm stud kits with installation tools.
- Disconnect the negative battery cable.
- Remove the rocker arm cover as outlined in this section
- For all engines, except 1996 5.7L (VIN 5) engines, remove the rocker arm nuts, balls and rocker arms.
- For 1996 5.7L (VIN 5) engines, remove the rocker and nuts and rocker arms.
- If necessary, you can remove the pushrods at this time. Place components in a rack so they can be reinstalled in the same location.
- Coat the bearings surfaces with a thin coating of Molykote® or its equivalent.
- Install the pushrods and make sure the rod is properly seated in the lifter seat.
- Install the rocker arm, balls (if equipped) and nut. For all engines, except the VIN 5, tighten the nut until all lash is eliminated. This can be determined by rotating the pushrod while turning the adjusting nut.
For vehicles through 1995, adjust the valves as follows:
- The engine must be on the No. 1 firing position before proceeding. This may be determined by placing your fingers on the No. 1 rocker arms as the mark crankshaft damper is rotated towards the "0" on the timing tab. If the arms did not move, it is in the No. 1 firing position. If they did move, turn the crankshaft one full revolution to reach the No. 1 position. Remember, the mark on the crankshaft balancer must be aligned with the "0" on the timing tab.
- With the engine on the number 1 firing position, exhaust valves 1, 3, 4 and 8, intake valves 1, 2, 5 and 7 may be adjusted.
- Back out the adjusting nut until lash is felt at the pushrod. Tighten the adjusting nut until all lash is removed, then tighten an additional 1 turn to center the lifter plunger.
- Turn the engine one revolution until the 0 timing mark is once again aligned. Exhaust valves 2, 5, 6 and 7, intake valves 3, 4, 6 and 8 may be adjusted.
- For 1996 5.7L (VIN 5) engines, install the rocker arm nuts and tighten to 18 ft. lbs. (25 Nm).
- Install the rocker arm cover.
- Connect the negative battery cable.