Rocker Arms and Pushrods

VALVE ROCKER ARMS AND PUSHRODS

Rocker Arms And Pushrods:

REMOVE OR DISCONNECT
1. Valve rocker cover; one or both.
2. Rocker arm nuts, rocker arm balls, rocker arms, and pushrods.
3. Place rocker arm balls, rocker arms, and pushrods in a rack so they may be reinstalled in the same locations.

INSTALL OR CONNECT

IMPORTANT
^ Rocker arm studs that have damaged threads should be replaced with new studs. Coat threads of rocker arm stud with sealing compound, GM P/N 1052080 or equivalent.

NOTICE: Whenever new rocker arms and/or rocker arm balls are being installed, coat bearing surfaces of rocker arms and rocker arm balls with prelube, GM P/N 3755008 or its equivalent.

1. Pushrods. Be sure pushrods seat in lifter socket.
2. Rocker arms, rocker arm balls, and nuts. Finger tighten.
3. Adjust valves when lifter is on base circle of camshaft lobe as follows:
a. Rotate engine until mark on torsional damper lines up with the "0" mark on the engine front cover timing tab, and the engine is in the # 1 cylinder firing position. This may be determined by observing the # 1 cylinder valves as the mark on the damper comes near the "0" mark. If both intake and exhaust valves are closed, the engine is in the # 1 cylinder firing position. If either valve is off its seat as the mark comes up to the timing tab, the engine is in # 6 cylinder firing position and should be rotated 360° to reach the # 1 cylinder position. The # 1 cylinder firing position can also be detected by a gust of air exiting the spark plug hole as the piston approaches "TDC".
b. With the engine in the # 1 firing position, the following valves may be adjusted:

^ Exhaust -- 1, 3, 4, 8.

^ Intake -- 1, 2, 5, 7.

c. Tighten rocker arm nuts until there is no movement of the pushrod. This can be determined by rotating pushrod while turning adjusting nut. Turn adjusting nut an additional 360°.
d. Rotate the crankshaft one revolution until the pointer "0" mark and torsional damper mark are again in alignment. This is the # 6 cylinder firing position. With the engine in this position, the following valves may be adjusted:

^ Exhaust -- 2, 5, 6, 7.

^ Intake -- 3, 4, 6, 8.

4. Install rocker arm covers.