Valve Rocker Arm and Shaft Cleaning and Inspection. Chevrolet Metro 1998

For 1990-2009 cars

### 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 to measure the runout of the rocker arm shaft.

Rocker Arm Shaft Runout
Maximum Runout = 0.20 mm (0.008 in)

2. If the measured runout exceeds the specifications, replace the rocker arm shaft.

### Rocker Arm Inspection

1. Inspect the tips and cam-riding face 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 in)

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 in)

3. Subtract the rocker arm inside diameter from the rocker arm shaft outside diameter and this will 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 in)

4. If the measured clearance exceeds the specifications, replace the rocker arm components as necessary.