Replacing a Head Gasket on a Pontiac Sunbird 2.0

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The 1982 through 1986 Pontiac Sunbird featured three engines: the 1.8-liter, 2.0-liter and 2.2-liter engines. All require the same process to replace the head gasket. The head gasket is made with a composite material and a steel core, and may "blow" if you overheat the vehicle. If you remove the head to find that the gasket is not bad, it must still be replaced because you cannot reuse the head gasket. The head bolts are torque-to-yield, and therefore must be replaced with new bolts.

Things You'll Need

  • Set of wrenches
  • Drain pan
  • Set of sockets
  • Floor jack
  • Jack stands
  • Tape and marker
  • Screwdriver
  • Set of line wrenches
  • Plastic scraper
  • Shop rags
  • Sealing compound
  • Torque wrench
  • Locate the relay box near the driver side fender well. Lift the cover off the relay box, and using the diagram on the underside of the cover, locate the fuel pump relay. Pull the relay out of its socket. Start the engine and allow it to run until it stalls, to relieve fuel pressure in the fuel system. If the engine will not start, crank it over five or six times to relieve the fuel pressure.

  • Disconnect the negative battery cable, using the appropriate wrench, then set it aside, making sure that it does not touch metal. Slide the drain pan under the radiator, open the petcock and remove the radiator cap to drain the coolant.

  • Remove the air cleaner assembly, using the appropriate socket. Raise the vehicle using the floor jack, and support it with jack stands. Remove the exhaust shield using the appropriate socket, then disconnect the exhaust pipe. Loosen the clamp on the heater hose at the intake manifold using the screwdriver, then pull the heater hose off the intake. Lower the vehicle using the floor jack.

  • Unscrew the mounting bolts on the engine lift bracket and air management system, then remove the lift bracket and air management as an assembly. Match-mark the distributor from the base to the intake manifold so you can reinstall it in its proper position. Unplug the wiring harness connectors, then remove the distributor using the appropriate sockets.

  • Label all vacuum lines and wiring harness connectors using the tape and marker. Remove the vacuum lines and wiring harness connectors. Disconnect the vacuum manifold at the back of the alternator bracket and remove the air management pipe at the exhaust check valve using the appropriate wrench.

  • Disconnect the accelerator linkage at the throttle body unit, remove the linkage bracket using the appropriate socket and lay the linkage out of the way. Loosen the hose clamp on the upper radiator hose at the thermostat, then pull the hose off the thermostat.

  • Remove the bolt that attaches the dipstick tube, then remove the dipstick tube and bracket. Loosen the adjusting bolts for the accessory drive belts and push each accessory toward the center of the engine to relive tension on the belts. Lift the belts off the pulleys, and remove the idler pulley using the appropriate socket.

  • Unbolt the power steering pump, but do not remove the lines. Lay the pump out of the way. Disconnect the fuel lines at the throttle body, using the appropriate line wrench. Unbolt the alternator, but do not remove the wires. Set the alternator aside. Remove the alternator upper mounting bracket using the appropriate socket.

  • Remove the valve cover using the appropriate socket. Remove the rocker arms and pushrods using the appropriate socket, and lay them out in the order you took them off, because they must be reinstalled in the same positions.

  • Remove the head bolts in the reverse order as shown in the illustration that is in the first entry in the References section below. Lift the head, intake and exhaust manifold off as an assembly. Clean the gasket mating surfaces of the engine and head, using the plastic scraper and shop rags.

  • Position the new head gasket on the dowel pins on the block and guide the head gasket into place. Coat the head bolts with sealing compound, then install them finger tight.

  • Tighten the bolts to 18 foot-pounds of torque in the sequence outlined in the same referenced illustration. Turn the bolts an additional 60 degrees. Turn the bolts an additional 60 degrees a second time, and finally turn the bolts an additional 30 degrees.

  • Reinstall the rocker arms and pushrods in their original locations. Adjust the valves when the lifter is on the base circle of a camshaft lobe. Crank the engine until the mark on the crankshaft pulley lines up with the "0" mark on the timing tab. Make sure that the engine is in the number one firing position by placing your fingers on the number one rocker arms as the mark on the crankshaft pulley gets close to the "0" mark. If the valves do not move as you are bumping the engine over, the engine is in the number one firing position.

  • Adjust the number one and three cylinder exhaust valves and the number one and two intake valves at this position, by backing the adjusting nut out until lash can be felt at the pushrod (free-play), then turn the nut until all the lash has been removed (no freeplay). The easiest way to "find" freeplay is to turn the pushrod between your thumb and forefinger while loosening or tightening the nut: As soon as the pushrod turns while loosening the nut, you have free-play. While tightening, as soon as the pushrod stops turning, there is no lash or free-play.

  • Turn the nut an additional 1-1/2-turns once you remove the lash. Rotate the engine one complete turn, until the "0" mark lines up with the timing tab again. Adjust the exhaust valves on cylinders two and four, and the intake valves on cylinders three and four the same way you just adjusted the other valves.

  • Reinstall the valve cover and the rest of the parts in reverse order of removal. Fill the radiator with 50/50 antifreeze. Reconnect the negative battery cable. Start the engine and allow it to come to operating temperature. At this time, the thermostat opens and allows the coolant to flow. Add coolant as needed.

Tips & Warnings

  • Make sure that the engine is cold prior to starting this procedure.
  • Discard the coolant in an appropriate manner. It is poisonous to animals and detrimental to the environment.

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