GM 12522105 Arm Kit,Valve Rocker

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When installing pivot balls and nuts, ensure the flat side of each nut faces the pivot ball.

To remove rocker arms and pivot balls, first loosen the rocker arm bolts and then remove the rocker arm nuts, rocker arms, and pivot balls. Carefully store them in marked containers for proper reinstallation.

Only loosen each nut enough to rotate the rocker arms to the side for push rod removal.

Reinstall the rocker arm covers, start the engine, check for unusual valve train noises, and inspect for oil leaks at the rocker arm cover joints.

To inspect and remove rocker arms and pushrods, begin by detaching the valve cover from the cylinder head. When removing them, it's crucial to ensure that a specific cylinder is at Top Dead Center (TDC), and the lifters for that cylinder are on the base circle of the camshaft. Rotate the crankshaft to position the piston at its highest point using a plastic pen in the spark plug hole to indicate TDC. Loosen the rocker arm bolts and remove the rocker arm nuts, rocker arms, and pivot balls while carefully storing them in marked containers. For pushrod removal, rotate the rocker arms aside to facilitate pushrod extraction. Additionally, pay attention to pushrod guides if they need to be removed, marking them for proper reinstallation. Examine rocker arms for wear, cracks, and damage, especially where they contact pushrods and valve stems. Ensure that the pushrod-end hole in each rocker arm is open and inspect the rocker arm pivot area for wear, cracks, and galling. Replace worn or damaged rocker arms and use new pivot balls if needed. Lubricate pushrod lower ends with engine oil or moly-base grease, install them in their original locations, and ensure they seat properly in the lifter socket. Apply moly-base grease to valve stem ends and upper pushrod ends before positioning rocker arms and installing bolts. Place rocker arms, install pivot balls and bolts, and tighten rocker arm nuts, taking care to tighten them when there is no valve spring load on the rocker arm. On later models, align the tab on the roller rocker pivot with the slot in the cylinder head casting protrusion. After tightening the rocker arms, reinstall the valve cover, start the engine, and check for oil leaks or valvetrain noises.

To remove the valve covers, start by detaching them from the cylinder heads. Proceed to loosen and remove the rocker arm stud nuts, starting at the front of one cylinder head. Store these nuts separately in marked containers to ensure proper reinstallation. For models through 1998, if only the pushrods need removal, loosen each nut just enough to rotate the rocker arms aside for pushrod removal. In 2000 and later models, roller-rocker arms are retained by bolts instead of pivot balls. Lift off the rocker arms and pivot balls, and store them with the nuts for later reinstallation. Remove the pushrods and store them separately to avoid mixing them up during installation, utilizing a perforated cardboard box for organized storage. Inspect each rocker arm for wear, cracks, and damage, focusing on the areas where pushrods and valve stems contact the rocker arm faces. Ensure the hole at the pushrod end of each rocker arm is open and check the rocker arm pivot area for wear, cracks, and galling. If any rocker arms are worn or damaged, replace them along with new pivot balls, especially on 2000 and later models with roller rocker arms. Inspect the pushrods for cracks and excessive wear, checking for bending by rolling them on a flat surface. To install, lubricate the lower end of each pushrod with clean engine oil or moly-base grease, seat them in their original lifter positions, and apply moly-base grease to valve stem and pushrod ends before positioning the rocker arms over the studs. Install pivot balls and nuts, ensuring the flat side of each nut faces the pivot ball. Tighten the rocker arm nuts. Reassemble the remaining components in reverse order, starting the engine and checking for valve cover leaks and valvetrain noise. Note that valve adjustment is not required for most models; however, specific instructions for valve adjustment on 1994 VIN Z engines are provided, involving setting the engine to TDC, aligning timing marks, and adjusting rocker arm nuts for specified valves at TDC for each cylinder.

Reassemble the remaining components in reverse order.

When removing pushrod guides, mark them for proper reinstallation. This is important to ensure they are placed back in their original positions.

Storing the rocker arm stud nuts separately in marked containers ensures proper reinstallation.

Ensuring a specific cylinder is at TDC and the lifters for that cylinder are on the base circle of the camshaft is important to prevent valve and piston interference when removing rocker arms and pushrods.