REMOVAL & INSTALLATION
The engine must be removed from the vehicle to remove the cylinder heads. Although it is physically possible (on some models) to remove the cylinder heads with the engine installed, head gasket failure will result upon installation, due to misalignment of the cylinders. The cylinder heads should be removed with the engine cold to prevent warpage.
- Remove the engine from the vehicle and mount it on a workstand.
- Unbolt and remove the intake manifold together with the carburetor/throttle body and the various pollution control devices. On 1977 and later models, remove the EGR pipe from the intake manifold and cylinder head. On 1982-84 models, this includes removing the thermostatic water valve and hose and the oil filler pipe brackets. On the turbocharged models, remove the turbocharger and exhaust manifold, and disconnect the fuel injection lines.
- Remove the spark plugs.
- Disconnect the crankcase ventilation hose(s) and remove the valve covers.
- Loosen the alternator adjusting bolts, and unbolt the alternator bracket from the cylinder head.
- Remove the air injection distributor tubes from the cylinder heads by unscrewing the fittings on models so equipped.
- On the 1800 Turbo, remove the knock sensor with a 27mm deep well socket only! (A standard socket will damage electrical terminals). Then, remove the fuel injectors.
- Loosen the valve rocker locknuts and adjusting screws (solid lifter engines only). Loosen the rocker shaft mounting nuts, and remove the rocker arm assembly and pushrods.
- Gradually loosen the head bolts using the correct sequence. If a loosening sequence is not illustrated, reverse the tightening sequence given. Remove the cylinder heads and gaskets.
- Construct a cylinder head spacer as shown in the illustration. Assemble the cylinder head on the engine and use the spacer in place of the rocker shaft support. After the cylinder head is tightened to specification following the correct sequence, remove the rocker shaft bolts (or nuts) and spacers, then install the rocker shafts.
- Install the remaining components in the reverse order of removal.
CLEANING & INSPECTION
Invert the cylinder head and clean the carbon from the valve faces and combustion chambers. Use a permanent felt-tip marker and mark the valves for location.
Use a valve spring compressor and compress the valve springs. Lift out the keepers, release the valve spring compressor and remove the valve, spring and spring retainer. Place all parts removed in order so that they can be reinstalled on the same cylinder.
Remove the valves from the cylinder head. Chip away any remaining carbon from the valve heads, combustion chambers and ports. Use a rotary wire brush on an electric drill. Be sure that the deposits are actually removed, rather than burned. Clean the valve faces with a wire wheel taking care not to remove the location numbering. Clean the cylinder head and component parts in an engine cleaning solvent.
Remove the pushrods, and, if hollow, clean out the oil passages using fine wire. Roll each pushrod over a piece of clean glass. If a distinct clicking sound is heard as the pushrod rolls, the rod is bent, and must be replaced.
Remove lifters from their bores, and remove gum and varnish, using solvent. Clean walls of lifter bores. Check lifters for concave wear as illustrated. If face is worn concave, replace lifter, and carefully inspect the camshaft. Lightly lubricate lifter and insert it into its bore. If play is excessive, an oversize lifter must be installed (where possible). Consult a machinist concerning feasibility. If play is satisfactory, remove, lubricate, and reinstall the lifter.
Check the cylinder head for warpage by placing a straightedge across the gasket surface. Using feeler gauges, determine the clearance at the center of the straight edge. Measure across the diagonals, along the longitudinal centerline and across the cylinder head at several points. Should the warpage exceed 0.002 in. the cylinder head must be resurfaced, be sure to observe the following grinding limits: ff-1, 0.0197 in.; all other models, 0.020 in.