For 1990-2009 cars

## Cylinder Head Replacement Left

#### Special Tools

J 36660-A Torque Angle Meter

### Removal Procedure

Important: During disassembly, keep the valve train components together and identified so that they can be installed in their original locations.

Do a compression test and note the results before you do the following repairs:

• | Remove the cylinder head(s)

• | Disassemble the valve mechanism

1. Depressurize the fuel system. Refer to Fuel Pressure Relief for the 3.1L engine.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

2. Disconnect the negative battery cable.
3. Drain the cooling system. Recover the cooling system. Refer to Cooling System Draining and Filling .
4. Remove the top half of the air cleaner assembly. Remove the throttle body duct.
5. Remove the exhaust crossover heat shield.
6. Remove the exhaust crossover.
7. Remove the valve rocker arm cover. Refer to Valve Rocker Arm Cover Replacement .
8. Remove the intake manifold. Refer to Intake Manifold Replacement .
9. Remove the left exhaust manifold. Refer to Exhaust Manifold Replacement .
10. Remove the oil level indicator. Refer to Oil Level Indicator and Tube Replacement .

Important: Keep the pushrods in order. Install the pushrods in the original position.

11. Remove the pushrods.
12. Remove and discard the cylinder head bolts.
13. Remove the cylinder head.
14. Clean the mating surfaces on the following items:

• | Cylinder head

• | Cylinder block

• | Intake manifold

15. Clean the cylinder block bolt threads.

### Installation Procedure

1. Place the cylinder head gasket in position over the dowel pins. Ensure that the This Side Up note is showing.
2. Install the cylinder head.

Notice: Refer to Fastener Notice in the Preface section.

Notice: This component uses torque-to-yield bolts. When servicing this component do not reuse the bolts, New torque-to-yield bolts must be installed. Reusing used torque-to-yield bolts will not provide proper bolt torque and clamp load. Failure to install NEW torque-to-yield bolts may lead to engine damage.

3. Install the NEW cylinder head bolts.

Tighten
Tighten the bolts to 60 N·m (44 lb ft) in the sequence shown. Use the J 36660-A to tighten the bolts an additional 95 degrees.

4. Install the intake gasket.
5. Install the pushrods in their original locations.

• | Coat the pushrod ends with prelube.

• | Use GM P/N 1052356 or the equivalent.

• | The intake pushrods are 144 mm (5.75 in).

• | The exhaust pushrods are 152.5 mm (6.0 in).

• | Make sure that the pushrods seat in the lifter.

6. Install the valve rocker arm bolts. Refer to Valve Rocker Arm and Push Rod Replacement .
7. Install the intake manifold. Refer to Intake Manifold Replacement .
8. Install the valve rocker cover. Refer to Valve Rocker Arm Cover Replacement .
9. Install the oil level indicator. Refer to Oil Level Indicator and Tube Replacement .
10. Install the left exhaust manifold. Refer to Exhaust Manifold Replacement .
11. Install the exhaust crossover pipe.

Tighten
Tighten the exhaust crossover pipe nuts/studs to 25 N·m (18 lb ft).

12. Install the exhaust crossover heat shield.

Tighten
Tighten the exhaust crossover heat shield bolts to 10 N·m (89 lb in).

13. Fill the cooling system. Refer to Cooling System Draining and Filling .
14. Install the throttle body duct. Install the top half of the air cleaner assembly.
15. Connect the negative battery cable.

## Cylinder Head Replacement Right

#### Special Tools

J 36660-A Torque Angle Meter

### Removal Procedure

Important: During disassembly, keep the valve train components together and identified so that they can be installed in their original locations.

Do a compression test and note the results before you do the following repairs:

• | Remove the cylinder head(s)

• | Disassemble the valve mechanism

1. Depressurize the fuel system. Refer to Fuel Pressure Relief for the 3.1L engine.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

2. Disconnect the negative battery cable.
3. Drain the cooling system. Recover the cooling system. Refer to Cooling System Draining and Filling .
4. Remove the top half of the air cleaner assembly. Remove the throttle body duct.
5. Remove the exhaust crossover heat shield.
6. Remove the exhaust crossover from both of the exhaust manifolds.
7. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
8. Remove the right exhaust manifold. Refer to Exhaust Manifold Replacement .
9. Lower the vehicle.
10. Remove the spark plug wires at the right cylinder head.
11. Remove the valve rocker cover. Refer to Valve Rocker Arm Cover Replacement .
12. Remove the intake manifold. Refer to Intake Manifold Replacement .

Important: Keep the pushrods in order. Install the pushrods in the original position.

13. Remove the pushrods.
14. Remove and discard the cylinder head bolts.
15. Remove the cylinder head.
16. Clean the mating surfaces on the following items:

• | Cylinder head

• | Cylinder block

• | Intake manifold

17. Clean the cylinder block bolt threads.

### Installation Procedure

1. Place the cylinder head gasket in position over the dowel pins. Ensure that the This Side Up note is showing.
2. Install the cylinder head.

Notice: Refer to Fastener Notice in the Preface section.

Notice: This component uses torque-to-yield bolts. When servicing this component do not reuse the bolts, New torque-to-yield bolts must be installed. Reusing used torque-to-yield bolts will not provide proper bolt torque and clamp load. Failure to install NEW torque-to-yield bolts may lead to engine damage.

3. Install the NEW cylinder head bolts.

Tighten
Tighten the bolts to 60 N·m (44 lb ft) in the sequence shown. Use the J 36660-A in order to tighten the bolts an additional 95 degrees.

4. Install the intake gasket.
5. Install the pushrods in the original locations.

• | Coat the ends of the pushrods with prelube.

• | Use GM P/N 1052356 or the equivalent.

• | The intake pushrods are 144 mm (5.75 in).

• | The exhaust pushrods are 152.5 mm (6.0 in).

• | Make sure that the pushrods seat in the lifter.

6. Install the valve rocker arm bolts. Refer to Valve Rocker Arm and Push Rod Replacement .
7. Install the intake manifold. Refer to Intake Manifold Replacement .
8. Install the valve rocker cover. Refer to Valve Rocker Arm Cover Replacement .
9. Install the spark plug wires to the cylinder head.
10. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
11. Install the right exhaust manifold. Refer to Exhaust Manifold Replacement .
12. Lower the vehicle.
13. Install the exhaust crossover at the right manifold.

Tighten
Tighten the exhaust crossover manifold to nut/stud to 25 N·m (18 lb ft).

14. Install the exhaust crossover heat shield.

Tighten
Tighten the exhaust crossover heat shield bolts to 10 N·m (89 lb in).

15. Fill the cooling system. Refer to Cooling System Draining and Filling .
16. Install the throttle body duct. Install the top half of the air cleaner.
17. Connect the negative battery cable.