Cylinder Head & Gasket Surface - Cleaning & Inspection
WARNING: This page is about a different car, the 2002 Pontiac Sunfire and 2002 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
- Use the following procedure to remove the cylinder head cup plugs:
- 1.1. Obtain a suitable self-threading screw.
- 1.2. Drill a hole in the plug.
- 1.3. Install the self-threading screw.
- 1.4. Pry out the plug and discard it.
- 1.5. Remove the spark plugs.
- Inspect the cylinder head gasket and mating surfaces for leaks, corrosion and blow-by. If the gasket has failed, use the following faults to determine the cause:
- Improper installation.
- Loose or warped cylinder head.
- Missing, off location or not fully seated dowel pins.
- Corrosion in the seal area around the coolant passages.
- Chips or debris in the cylinder head bolt holes.
- Bolt holes in the cylinder block not drilled or tapped deep enough.
- Other.
- Inspect the cylinder head gasket surface.
- The cylinder head may be reused if corrosion is found only outside a 4 mm (0.375 in) band around each combustion chamber (1).
- Replace the cylinder head if the area between the valve seats is cracked (2).
- Replace the cylinder head if corrosion has been found inside a 4 mm (0.375 in) band around each combustion chamber (3).
- Clean the cylinder head bolts.
Important: Do not use a wire brush on any gasket sealing surface.
- Clean the cylinder head. Remove all varnish, soot and carbon to the bare metal.
- Clean the valve guides.
- Clean the threaded holes. Use a nylon bristle brush.
- Clean the remains of the sealer from the plug holes.
- Inspect the cylinder head bolts for damaged threads or stretching and damaged heads caused by improper use of tools.
- Replace all suspect bolts.
Important: Do not attempt to weld the cylinder head. Replace the cylinder head instead.
- Inspect the cylinder head deck for corrosion, sand inclusions and blow holes.
- Inspect the cylinder head deck, the intake, and exhaust manifold mating surfaces for flatness. These surfaces may be reconditioned by parallel grinding.
- Use the following steps to determine the amount of reconditioning needed:
- If the warpage is less than 0.076 mm (0.003 in), reuse the cylinder head, but do not resurface.
- If the warpage is between 0.076 mm (0.003 in) and 0.25 mm (0.010 in), resurface the cylinder head before reusing.
- If the warpage is over 0.25 mm (0.010 in), discard the cylinder head.
- Inspect all the threaded holes for damage. The threads may be reconditioned with thread inserts.
- Inspect the sealing surfaces.
- Inspect the cylinder head cup plugs.