REMOVAL AND INSTALLATION
4 and 6-Cylinder Engines
- Drain the cooling system and remove the air cleaner. Disconnect the PCV hose.
- Disconnect the choke cable (four-cylinder), the accelerator pedal rod at the bellcrank on the manifold, and the fuel and vacuum lines at the carburetor.
- Disconnect the exhaust pipe at the manifold flange, then remove the manifold bolts and clamps and remove the manifolds and carburetor as an assembly.
- Remove the fuel and vacuum line retaining clip from the water outlet. Disconnect the wire harness from the heat-sending unit and coil, leaving the harness clear of the clips on the rocker arm cover.
- Disconnect the radiator hose from the water outlet housing and the battery ground strap at the cylinder head.
- Tag and disconnect the wires and remove the spark plugs. On the six-cylinder engine, disconnect the coil-to-distributor primary wire lead at the coil and remove the coil.
- Remove the rocker arm cover. Back off the rocker arm nuts, pivot the rocker arms to clear the pushrods, and remove the pushrods.
- Remove the cylinder head bolts, cylinder head, and gasket.
- Place a new cylinder head gasket over the dowel pins in the cylinder block.
- Guide and lower the cylinder head into place over the dowels and gasket.
- Oil the cylinder head bolts, install, and run them down snugly.
- Tighten the cylinder head bolts a little at a time with a torque wrench in the correct sequence. Final torque should be 90-95 ft lbs.
- Install the valve pushrods down through the cylinder head openings and seat them in their lifter sockets.
- Install the rocker arms, balls, and nuts, and tighten the rocker arm nuts until all pushrod play is taken up.
- Install the thermostat, thermostat housing, and water outlet, using new gaskets. Connect the radiator hose.
- Install the heat-sending switch and torque to 15-20 ft lbs.
- Clean the spark plugs or install new ones. Set the gaps.
- Torque 13 / 16 in. hex plugs to 20 ft lbs. and 5 / 8 in. hex plugs to 15 ft lbs. Tapered seat plugs are used on some engines starting in 1970 and all engines beginning in 1971.
- Install the coil (on six-cylinder engines) then connect the heat-sending unit and coil primary wires, and connect the battery ground cable at the cylinder head.
- Clean the surfaces and install a new gasket over the manifold studs. Install the manifold. Install the bolts and clamps and torque as specified.
- Connect the throttle linkage and the choke wire (on the four-cylinder engine).
- Connect the PCV, fuel, and vacuum lines and secure the lines the clip at the water outlet.
- Fill the cooling system and check for leaks.
- Adjust the valve lash.
- Install the rocker arm cover and position the wiring harness in the clips.
- Clean and install the air cleaner.
- Remove the intake manifold as described in the appropriate procedure in this section.
- Remove the rocker cover. Loosen rocker arm nuts, and then rotate rocker arms to disengage them from the pushrods. Mark pushrod locations, and then remove them.
- Drain the cooling system into a suitable container.
- Remove fuel and vacuum lines from the clip at the thermostat housing, and disconnect all wiring from temperature sending units. Where engine has an air pump, disconnect the air injection hose at the check valve.
- Disconnect battery ground strap. Disconnect upper radiator hose from the thermostat housing.
- Remove cylinder head bolts, and then remove head and gasket. Inspect the head for warpage and cracks, as described below in the rebuilding section.
Make sure gasket surfaces on both head and block are clean of foreign matter, and free of any nicks or heavy scratches. Bolt threads and female thread in the block must be clean. Do not use gasket sealer with a composition steel and asbestos gasket.
- Coat gasket with sealer, unless it's a composition gasket. Position the gasket over the dowel pins.
- Carefully guide the head into position over the dowel pins and gasket.
- Coat threads of all cylinder head bolts