Spark

Cylinder Head Cleaning and Inspection

1. Remove any old thread sealant, gasket material or sealant.
2. Clean all cylinder head surfaces with non-corrosive solvent.

Warning: Refer to Safety Glasses and Compressed Air Warning in the Preface section.

3. Blow out all the oil galleries using compressed air.
4. Remove any carbon deposits from the combustion chambers.
5. Clean any debris or build-up from the lifter pockets.

1. Inspect the cylinder head camshaft bearing surfaces for the following conditions:

•	Scoring or pitting above acceptable tolerances

•	Discolouration from overheating

•	Deformation from wear above acceptable tolerances

•	If the camshaft bearing journals appear to be scored or damaged, you must replace the cylinder head. DO NOT machine the camshaft bearing journals.

2. If any of the above conditions exist on the camshaft bearing surfaces, replace the cylinder head.
3. Inspect the cylinder head for the following:

•	Cracks, damage or pitting in the combustion chambers

•	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 - Deck Flatness Inspection.

•	Burrs or any defects that may degrade the sealing of the NEW secondary camshaft drive chain tensioner gasket

•	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 passages

•	Restrictions in the inlet or exhaust passages

•	Restrictions in the cooling system passages

•	Rusted, damaged or leaking core plugs

4. If the cylinder head is cracked or damaged, it must be replaced. No welding or patching of the cylinder head is recommended.

Deck Flatness Inspection

1. Ensure the cylinder head (1) decks are clean and free of gasket material.
2. Inspect the surface for any imperfections or scratches that may inhibit correct cylinder head gasket sealing.
3. Place a straight-edge (2) diagonally across the cylinder head (1) deck face surface.
4. Measure the clearance between the straight-edge (2) and the cylinder head (1) deck face using a feeler gauge at 4 points along the straight-edge (2).

•	If the warpage is less than 0.05 mm (0.002 in), the cylinder head (1) deck surface does not require resurfacing.

•	If the warpage is between 0.05-0.20 mm (0.002-0.008 in) or any imperfections or scratches that may inhibit correct cylinder head gasket sealing are present, the cylinder head (1) deck surface requires resurfacing.

•	If the cylinder head (1) deck surface requires more than 0.25 mm (0.010 in) material removal the cylinder head (1) must be replaced.