Buick Regal: Cylinder Head Disassemble

Special Tools

• EN-43963 Valve Spring Compressor (off car)
• EN-46116 Valve Stem Seal Remover/Installer
• EN-50717 Valve Spring Compressor

For equivalent regional tools, refer to Special Tools.

1.

Remove the intake camshaft position sensor (2) and bolt (1).

2.

Remove the exhaust camshaft position sensor (2) and bolt (1).

3.

WARNING: Compressed valve springs have high tension against the valve spring compressor. Valve springs that are not properly compressed by or released from the valve spring compressor can be ejected from the valve spring compressor with intense force. Use care when compressing or releasing the valve spring with the valve spring compressor and when removing or installing the valve stem keys. Failing to use care may cause personal injury.

CAUTION: Do not compress the valve springs to less than 24.0 mm (0.943 in). Contact between the valve spring retainer and the valve stem oil seal can cause potential valve stem oil seal damage.

NOTE: Ensure that the valve train components are kept together and identified in order for proper installation in their original position.

Perform the following procedure to remove the valve keys, springs, and retainers:

1. Using the EN-50717 fixture and the EN-43963 compressor adapter, compress the valve spring.
2. Remove the valve keys (1).
3. Slowly release the compression from the valve spring assembly.
4. Remove the retainer (2).

4.

Remove the springs (1).

5.

CAUTION: Do not damage the valve guide. Remove any burrs that have formed at the key groove by chamfering the valve stem with an oil stone or a file.

Using EN-46116 remover, remove the valve seals (1). Discard the seals, do not reuse.

6.

Remove the valves (1, 2).

7.

Remove the cylinder head plug (1).

8.

Remove the cylinder head plugs (1).

CYLINDER HEAD CLEANING AND INSPECTION

Special Tools

• EN 22738-B Valve Spring Tester
• EN-28410 Gasket Remover
• EN-39358 Spark Plug Socket
• GE 7872 Magnetic Base Dial Indicator

For equivalent regional tools, refer to Special Tools.

Valve Cleaning and Inspection

1.

NOTE: Do not use a wire brush on any part of the valve stem.

NOTE: Do not grind or condition the intake valve. If the intake valve is out of specification, replace the valve.

Clean the valves of carbon, oil and varnish. Use a soft bristle wire brush to clean any carbon build-up from the valve head. Varnish can be removed by soaking in Parts Immersion Solvent.

2. Clean the valve guides.

3. Inspect the valve stem for pitting or wear (4).

4. Inspect the valve key groove for chipping or wear (5). Replace the valve if chipped or worn.

5. Inspect the valve face for burning or cracking (1). If pieces are broken off, inspect the corresponding piston and cylinder head area for damage.

6. Inspect the valve stem for burrs and scratches. Burrs and minor scratches may be removed with an oil stone.

7. Inspect the valve stem for straightness (3) and the valve head for bending or distortion using V blocks. Bent or distorted valves must be replaced.

8. Clean the deposits from the valve face. Inspect the valve face for grooving.

9. Replace the valve if the face is grooved. Valve faces cannot be machined. If worn, or damaged, the valves must be replaced.

10. Replace the valve if the valve head O.D. and chamfer (2) is worn or out of specification. Refer to Valve and Seat Grinding.

11. The valves may be lightly lapped to the valve seats.

12. Replace the valve if the valve tip (6) is worn.

13. If no apparent wear, pitting, grooving, or distortion is present, perform the valve measurement and reconditioning procedure to verify valve specification. Refer to Valve and Seat Grinding.

Valve Guide Measurement

1.

Measure the valve stem (1)-to-guide (2) clearance. Excessive valve stem-to-guide clearance may cause an excessive oil consumption and may also cause a valve to break. Insufficient clearance will result in noisy and sticky functioning of the valve and will disturb the engine assembly smoothness.

2. Clamp the GE 7872 dial indicator to the cylinder head at the camshaft cover rail.

3. 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.

4. Drop the valve head about 0.064 mm (0.0025 in) off the valve seat.

5. Use light pressure when moving the valve stem from side to side in order to obtain a clearance reading. Refer to Engine Mechanical Specifications for proper clearance.

NOTE: Valve guide wear at the bottom 10 mm (0.390 in) of the valve guide is not significant to normal operation.

6. If the clearance for the valve is greater than specifications and a new standard diameter valve stem will not bring the clearance within specifications, replace the cylinder head.

Valve Spring Cleaning and Inspection

1. Clean the valve springs in solvent.

WARNING: Refer to Safety Glasses Warning.

2. Dry the valve springs with compressed air.

3. Inspect the valve springs for broken coils or coil ends.

4.

Measure the valve spring tension using the EN 22738-B tester. Refer to Engine Mechanical Specifications 5. If low valve spring load is found, replace the valve springs. DO NOT use shims to increase spring load. The use of shims can cause the valve spring to bottom out before the camshaft lobe is at peak lift.

Valve Rocker Arm Cleaning and Inspection

1.

Inspect the camshaft follower roller (1) for the following:

• Flat spots
• Excessive scoring and pitting
• Ensure the roller spins freely

2. Inspect the camshaft follower valve tip area (2).

3. Inspect the camshaft follower stationary hydraulic lash adjuster (SHLA) pivot area (3).

4. Replace the camshaft follower or followers as necessary.

Cylinder Head and Gasket Surface Cleaning and Inspection

1.

Remove the spark plugs (1) using EN-39358 socket.

2. 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:

1. Improper installation
2. Loose or warped cylinder head
3. Missing, off location or not fully seated dowel pins
4. Corrosion in the seal area around the coolant passages
5. Chips or debris in the cylinder head bolt holes
6. Bolt holes in the cylinder block not drilled or tapped deep enough

3.

Inspect the cylinder head gasket surface.

• 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).

4. Ensure proper use of room temperature vulcanizing (RTV) sealant.

NOTE: Do not use a wire brush on any gasket sealing surface.

5. Remove the sealant from the rear cap mating surface with EN-28410 remover. Care must be used to avoid gouging or scraping the sealing surfaces.

6. Clean the cylinder head. Remove all varnish, soot and carbon to the bare metal.

7. Clean the valve guides.

8. Clean the threaded holes. Use a nylon bristle brush.

9. Clean the remains of the sealer from the plug holes.

10. Inspect the cylinder head for cracks. Check between the valve seats and in the exhaust ports.

NOTE: Do not attempt to weld the cylinder head, replace it.

11. Inspect the cylinder head deck for corrosion, sand inclusions and blow holes.

12.

Using a straight edge (1) and feeler gauge (2), inspect the cylinder head deck surface for flatness. Refer to Engine Mechanical Specifications. If the cylinder head is out of specification, replace the cylinder head. Do not machine the cylinder head.

13. Inspect all the threaded holes for damage. Threads may be reconditioned with thread inserts.

14. Inspect the sealing surfaces.

15.

Inspect the intake camshaft bearing rear cap (2) for damage.

16. Inspect the camshaft bearing caps (1) for damage.

17. Inspect the camshaft front upper and lower bearing caps (3, 4) for damage.

18.

CAUTION: Refer to Component Fastener Tightening Caution.

Install the spark plugs (1) using EN-39358 socket. Tighten the plugs to 20 N.m (15 lb ft).

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