Cylinder Head Assembly: Testing and Inspection

NOTES
^ During disassembly of the cylinder head, be sure that the valvetrain components are kept to either and identified so that they can be installed in their original locations.
^ Before removing the cylinder head(s) from the engine and before disassembling the valve mechanism, perform a compression test and note the results.


Remove or Disconnect
1. Cylinder head. Refer to Cylinder Head Assembly / Service and Repair.
2. Rocker arm assemblies. Refer to Rocker Arm / Service and Repair.
3. Spark plug.

Depressing Valve Spring:

4. Compress the valve springs using J 38606.
5. Valve locks.
6. Valve caps.
7. Valve springs.
8. Spring seats.
9. Valve stem oil seals.
10. Valves.
11. Oil gallery (if equipped) and coolant jacket plugs.
^ Threaded plugs.
^ Cup plugs, if damaged or leaking:
a. Obtain a suitable self-threading screw.
b. Drill a hole in the plug.
c. Install the self-threading screw.
d. Pry out plug.


INSPECTION
^ Inspect cylinder head gasket and mating surfaces for leaks, corrosion and blow-by. If the gasket has failed, determine the cause:
- Improper installation.
- Loose or warped cylinder head.
- Missing, off location or not fully seated dowel pins.
- Low torque on cylinder head bolts.
- Warped case (block) surface.
- Scratched surfaces.
- Excessive inlet manifold torque.
- Cracked case (block) tapped holes.

CAUTION Safety glasses MUST be worn when using a power wire brush to avoid damage to the eyes.

CLEAN
^ Clean cylinder head bolts and cylinder head.
- Carefully remove all varnish, soot and carbon to the bare metal.
- DO NOT use a motorized wire brush on any gasket sealing surface.

Valve Guide Cleaner:

Cleaning Valve Guide:

^ Clean valve guides using J 8101.
^ Clean threaded holes.
^ Clean remains of sealer from plug holes.


INSPECTION
1. Inspect cylinder head bolts for damaged threads or stretching, and damaged heads caused by improper use of tools.

CAUTION Suspect bolts MUST be replaced.

2. Inspect cylinder head for cracks, especially between valve seats and in the exhaust ports.
3. Inspect cylinder head deck for corrosion, sand particles in head, and porosity.

CAUTION DO NOT attempt to weld the cylinder head, REPLACE it.

Checking Cylinder Head Flatness:

4. Inspect cylinder head deck, intake and exhaust manifold mating surfaces for flatness.
- These surfaces may be re-conditioned by milling.
- If the surfaces are "out of flat" by more than 0.127 mm 0.005 inch), the surface should be milled.
- If more than 0.25 mm (0.010 inch) of metal must be removed from the head, it should be REPLACED.
5. Inspect all threaded holes for damage. Threads may be reconditioned with thread inserts.
6. Inspect cooling jacket plugs seating surfaces, if plugs have been remove
7. Inspect valve guides, valves, valve seats and valve springs.