Check the rocker arm adjusting screws and the push
CLEANING AND INSPECTION
rod end of the rocker arms for stripped or broken threads,
The cleaning and inspection procedures are for a
and the ball end of the adjusting screw for nicks.
complete engine overhaul: therefore, for partial engine
scratches or excessive wear.
overhaul or parts replacement, follow the pertinent
cleaning or inspection procedure.
Clean the push rods in a suitable solvent.
Cleaning Remove all gasket material from the
machined surfaces of the manifold. Clean the manifold in
a suitable solvent and dry it with compressed air.
Check the ends of the push rods for nicks, grooves,
roughness or excessive wear.
The push rods can be visually checked for
Inspect the manifold for cracks. damaged gasket
straightness while they are installed in the engine by
surfaces. or other defects that would make it unfit for
rotating them with the valve closed. They also can be
further service. Replace all studs that are stripped or
checked with a dial indicator (Figure 10).
otherwise damaged Remove all filings and foreign matter
If the push rod is visibly bent, it should be replaced
that may have entered the manifold as a result of repairs.
Remove all gasket material from the manifolds.
Inspect the cylinder head Joining flanges of the
exhaust manifold for evidence of exhaust gas leaks.
Inspect the manifolds for cracks, damaged gasket
FIG. 10 Checking Push Rod Runout
surfaces, or other defects that would make them unfit for
VALVE ROCKER ARM AND/OR SHAFT ASSEMBLY
With the valves installed to protect the valve seats,
Cleaning Clean all the parts thoroughly. Make sure all
oil passages are open.
valve heads with a scraper and a wire brush. Be careful
Make sure the oil passage in the push rod end of the
not to damage the cylinder head gasket surface. After the
rocker arm is open.
valves are removed, clean the valve guide bores with a
valve guide cleaning tool. Using cleaning solvent to
remove dirt, grease and other deposits, clean all bolt
On rocker arm shaft assemblies. check the clearance
holes. Remove all deposits from the valves with a fine
between each rocker arm and the shaft by checking the
wire brush or buffing wheel.
ID of the rocker arm bore and the OD of the shaft. If the
clearance between any rocker arm and the shaft exceeds
the wear limit, replace the shaft and/or the rocker arm.
Check the cylinder head for cracks and inspect the
Inspect the shaft and the rocker arm bore for nicks,
gasket surface for burrs and nicks. Replace the head if it
scratches. scores or scuffs.
Inspect the pad at the valve end of the rocker arm for
indications of scuffing or abnormal wear. If the pad is
The following inspection procedures are for a cylinder
grooved, replace the rocker arm. Do not attempt to true
head that is to be completely overhauled. For individual
this surface by grinding.
repair operations, use only the pertinent inspection