Tools Required
Visual Inspection Procedure
- Inspect the cylinder head for the following:
 
| •  | Cracks, damage or pitting in the combustion chambers. | 
 
|     | Important: DO NOT machine the camshaft bearing journals.
 | 
| •  | Scoring of the camshaft bearings and/or the journals. If the camshaft bearing journals appear to be scored or damaged, you must replace the cylinder head. | 
 
| •  | Debris in the oil galleries. Continue to clean the galleries until all debris is removed. | 
 
| •  | Coolant leaks or damage to the deck face sealing surface. If coolant leaks are present, measure the surface warpage as described under Cylinder Head Measurement. | 
 
| •  | Damage to any gasket surfaces | 
 
| •  | Damage to any threaded bolt holes | 
 
| •  | Burnt or eroded areas in the combustion chamber | 
 
| •  | Cracks in the exhaust ports and combustion chambers | 
 
| •  | External cracks in the water chamber | 
 
| •  | Restrictions in the intake or exhaust passages | 
 
| •  | Restrictions in the cooling system passages | 
 
| •  | Rusted, damaged, or leaking core plugs | 
 
- If the cylinder head is cracked or damaged, it must be replaced. No welding or patching of the cylinder head is recommended.
 
- The oil passage from the left cylinder head deck face that feeds the stationary
hydraulic lifters (SHLAs) and the camshafts has a pressed-in restrictor. The orifice within the restrictor is 3 mm (0.1181 in). DO NOT remove the restrictor. Ensure the restrictor and oil passage are clean and free of any debris.
 
- Ensure the left cylinder head oil gallery
restictor is installed to the proper depth of 1.5-5.5 mm (0.059-0.216 in).
 
- The oil passage from the right cylinder head deck face that feeds the stationary
hydraulic lifters (SHLAs) and the camshafts has a pressed-in restrictor. The orifice within the restrictor is 3 mm (0.1181 in). DO NOT remove the restrictor. Ensure the restrictor and oil passage are clean and free of any debris.
 
- Ensure the right cylinder head oil
gallery restictor is installed to the proper depth of 1.5-5.5 mm (0.059-0.216 in).
 
Cleaning Procedure
- Clean all cylinder head surfaces with non-corrosive solvent.
 
Caution: Refer to Safety Glasses Caution in the Preface section.
- Blow out all the oil galleries using compressed air.
 
- Remove any carbon deposits from the combustion chambers using the 
J 8358 
 .
 
- Remove any gasket material with the 
J 28410 
 .
 
- Clean any debris or build-up from the lifter pockets.
 
- Inspect the cylinder head again for the items noted under Visual Inspection.
 
Cylinder Head Measurement
Notice: Refer to Fastener Notice in the Preface section.
- Measure the camshaft clearance specification using the following procedure:
 
| 1.1.  | Install the camshaft caps. | 
 
| 1.2.  | Install the camshaft caps bolts. | 
 
Tighten
Tighten the camshaft bearing caps bolts to 5 N·m (44 lb in).
| 1.3.  | Measure the camshaft bearings using an inside micrometer. | 
 
| 1.5.  | Subtract the camshaft journal diameter from the camshaft bearing diameter in order to obtain the running clearance. | 
 
| 1.6.  | If the running clearance exceeds the specifications and the camshaft journals are within specification, replace the cylinder head. Refer to 
Engine Mechanical Specifications
 . | 
 
- Measure the camshaft thrust specification using the following procedure:
 
| 2.1.  | Inspect each camshaft cap thrust surface for excessive scoring/wear. | 
 
| 2.3.  | Install the intake and exhaust camshafts in the cylinder head. | 
 
| 2.4.  | Install the camshaft caps. | 
 
| 2.5.  | Install the camshaft caps bolts. | 
 
Tighten
Tighten the camshaft bearing caps bolts to 5 N·m (44 lb in).
| 2.7.  | If the camshaft thrust bearing clearance is not to specification repair or replace the cylinder head. | 
 
- Measure the cylinder head flatness using the following procedure:
 
| 3.1.  | Clean any remaining head gasket material from the cylinder head face. | 
 
| 3.2.  | Place a straight-edge diagonally across the cylinder head face surface. | 
 
| 3.3.  | Measure the clearance between the straight-edge and the cylinder head using a feeler gage at four points along the straight-edge. | 
 
|    •  | If warpage is less than 0.05 mm (0.002 in), the cylinder head surface does not require resurfacing. | 
 
|    •  | If warpage is between 0.05-0.20 mm (0.002-0.008 in), the cylinder head must be resurfaced. | 
 
Valve Guide Measurement Procedure
- Measure the valve stem (1)-to-guide (2) clearance as follows:
 
| •  | Excessive valve stem-to-guide clearance may cause an excessive oil consumption and may also case a valve to break. Insufficient clearance will result in noisy and sticky functioning of the valve and will disturb the engine assembly smoothness. | 
 
| •  | Clamp the 
J 8001 
 to the cylinder head at the camshaft cover rail. | 
 
| •  | Locate the dial indicator so that the movement of the valve stem from side to side, crossways to the cylinder head, will cause a direct movement of the indicator stem. | 
 
| •  | The dial indicator stem must contact the side of the valve stem just
above the valve guide. | 
 
| •  | Drop the valve head about 1.6 mm (0.0064 in) off the valve seat. | 
 
| •  | Use light pressure when moving the valve stem from side to side in order to obtain a clearance reading. | 
 
- If the clearance for the intake valve is greater than 0.11 mm (0.0045 in) and a new standard diameter valve stem will not bring the clearance within specifications, the cylinder head must be replaced.
 
- If the clearance for the exhaust valve is greater than 0.12 mm (0.005 in) and a new standard diameter valve stem will not bring the clearance within specifications, the cylinder head must be replaced.
 
- Valve guide wear at the bottom 10 mm (0.39 in) of the valve guide is not significant to normal operation.