57. Cylinder Head Clean and Inspect
Cylinder Head Cleaning and Inspection^ Tools Required
- J 8001 Dial Indicator Set
- J 8358 Carbon Removal Brush
- J 28410 Gasket Remover
Visual Inspection Procedure
1. 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
2. If the cylinder head is cracked or damaged, it must be replaced. No welding or patching of the cylinder head is recommended.
Cleaning Procedure
1. Clean all cylinder head surfaces with non-corrosive solvent.
Caution: Refer to Safety Glasses Caution in Service Precautions.
2. Blow out all the oil galleries using compressed air.
3. Remove any carbon deposits from the combustion chambers using the J 8358.
4. Remove any gasket material with the J 28410.
5. Clean any debris or build-up from the lifter pockets.
6. Inspect the cylinder head again for the items noted under Visual Inspection.
Cylinder Head Measurement
Notice: Refer to Fastener Notice in Service Precautions.
1. Measure the camshaft clearance specification using the following procedure:
1.1. Install the camshaft caps.
1.2. Install the camshaft caps bolts.
Tighten the camshaft bearing caps bolts to 5 Nm (44 inch lbs.).
1.3. Measure the camshaft bearings using an inside micrometer.
1.4. Inspect and measure the camshaft journal diameters.
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.
2. Measure the camshaft thrust specification using the following procedure:
2.1. Inspect each camshaft cap thrust surface for excessive scoring/wear.
2.2. Inspect each camshaft.
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 the camshaft bearing caps bolts to 5 Nm (44 inch lbs.).
2.6. Measure the camshaft thrust bearing clearance at the front camshaft bearing cap.
2.7. If the camshaft thrust bearing clearance is not to specification repair or replace the cylinder head.
3. 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 inch), the cylinder head surface does not require resurfacing.
^ If warpage is between 0.05 - 0.20 mm (0.002 - 0.008 inch), the cylinder head must be resurfaced.