Operation CHARM: Car repair manuals for everyone.

29. Valve Rocker Arm and Shaft Clean and Inspect

Rocker Arm Shaft Inspection

^ Tool Required
- J 7872 Magnetic Base Dial Indicator Set





1. Place the rocker-arm shaft in two V-Blocks, and use a dial indicator in order to measure the runout of the rocker-arm shaft.
Rocker Arm Shaft Runout Maximum Runout = 0.20 mm (0.008 inch)
2. If the measured runout exceeds the specifications, replace the rocker-arm shaft.

Rocker Arm Inspection





1. Inspect the tips and the cam-riding face (3) of the rocker arms for excessive wear.
2. Replace any rocker arm that shows excessive wear.

Rocker Arm-to-Rocker Arm Shaft Clearance Inspection

^ Tools Required
- J 26900-5 Vernier Caliper
- J 26900-2 Outside Micrometer





1. Using an outside micrometer, measure the diameter of the rocker-arm shaft.
Standard Rocker Arm Shaft Diameter 15.969 - 15.984 mm (0.6287 - 0.6293 inch)
2. Using a Vernier caliper, measure the inside diameter of the rocker arm.
Standard Rocker Arm Inside Diameter 15.985 - 16.005 mm (0.629 - 0.630 inch)
3. Subtract the rocker arm inside diameter from the rocker-arm shaft outside diameter in order to determine the rocker-arm to rocker-arm shaft clearance. Standard Rocker Arm-to-Rocker Arm Shaft Clearance 0.001 - 0.036 mm (0.0001 - 0.0014 inch)
4. If the measured clearance exceeds the specifications, replace the rocker arm components as necessary.