Removal & Installation
When servicing the engine, be absolutely sure to mark vacuum hoses and wiring so that these items may be properly reconnected during installation. Also, when disconnecting fittings of metal lines (fuel, power brake vacuum), always use two flare nut (or line) wrenches. Hold the wrench on the large fitting with pressure on the wrench as if you were tightening the fitting (clockwise), THEN loosen and disconnect the smaller fitting from the larger fitting. If this is not done, damage (twisting) to the line will result.
Properly relieve the fuel system pressure before disconnecting any lines.
Before servicing the vehicle, refer to the Precautions Section.
NOTEDisconnecting the negative battery cable on some vehicles may interfere with the functions of the on-board computer systems and may require the computer to undergo a relearning process, once the negative battery cable is reconnected.
NOTEIf working near and/or around the SRS system and components, be sure to properly disable the SRS system. See disarming/arming the SRS system.
- Disconnect the negative battery cable.
- Relieve the fuel system pressure.
- Drain cooling system into a suitable container. Be sure to properly dispose of used coolant.
Remove the drive belt(s).
Remove the intake manifold.
- Remove the exhaust manifolds.
- Remove the diverter valve, if equipped.
- Disconnect the power steering pump, generator, and/or air conditioning brackets, as necessary, and position aside.
- Remove the rocker arm cover or valve cover.
- Tag and disconnect spark plug wires from the spark plugs. Disconnect ground strap and/or negative battery cable from cylinder head as applicable.
- Loosen cylinder head bolts gradually and in 3 passes.
- Clean dirt from cylinder head and adjacent area to avoid getting dirt into engine.
- If necessary, remove rocker arm assemblies and lift out pushrods.
Remove cylinder head.
Be sure to use new fasteners, as required.
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread sealer are identified. Do not use paints, lubricants or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners.
- Cylinder heads using a steel gasket should have both sides of the new gasket coated with a good sealer. The coating should be thin and even. Do not use sealer on composite type gaskets.
- Place gasket over dowel pins.
Place cylinder head over dowel pins and gasket.
- Coat the threads of the cylinder head bolts with sealing compound, part 1052080 or equivalent Install bolts finger-tight.
- Following the proper torque sequence, tighten the cylinder head bolts, in 3 passes, to 68 ft. lbs. (92 Nm).
- If removed, position pushrods and attach rocker arm assemblies. Adjust the valves.
- Connect spark plug wires, and the body ground strap.
- Attach rocker arm cover or valve cover.
- Attach power steering pump, generator and/or air conditioning brackets if removed. Install the diverter valve, the oil level indicator and tube, if removed.
- Attach the intake and exhaust manifolds.
- Attach both ends of the negative battery to cylinder head cable.
- Attach fuel filler cap, add coolant and inspect the engine for fluid leakage.
- Change the engine oil and filter.
- Start the engine and set the idle and timing to specification.
- Using the GM diagnostic scan tool or aftermarket equivalent reprogram the necessary systems and components. Be sure to follow the scan tool manufacturer-s directions.