Off Vehicle Service
REMOVAL - CYLINDER HEAD OFF1. With cylinder head removed from cylinder block, compress valve springs using a universal valve spring compressor.
2. Remove valve retaining locks, valve spring retainers, valve stem seals and valve springs.
3. Before removing valves, remove any burrs from valve stem lock grooves to prevent damage to the valve guides. Identify valves, locks and retainers to insure installation in original location.
4. Inspect the valves.
INSPECTION
1. Whenever valves have been removed for inspection, reconditioning or replacement, valve springs should be tested for correct tension. Discard the springs that do not meet specifications. The following specifications apply to both intake and exhaust valves springs:
^ Valve Closed Nominal Tension 76 lbs. @ 38.0 mm (1.50 in.)
^ Valve Open Nominal Tension 136 lbs. @ 29.75 mm (1.17 in.)
2. Inspect each valve spring for squareness with a steel square and surface plate, test springs from both ends. If the spring is more than 1.5 mm (1/16 in.) out of square, install a new spring.
INSTALLATION - CYLINDER HEAD OFF
1. Coat valve stems with clean engine oil and insert in cylinder head.
Fig.35:
2. Install new valve stem seals on all valves using a valve stem seal tool (Fig. 35). The valve stem seals should be pushed firmly and squarely over valve guide.
CAUTION: When oversize valves are used, the corresponding oversize valve seal must also be used. Excessive guide wear may result if oversize seals are not used with oversize valves.
3. Install valve springs and retainers. Compress valve springs only enough to install locks, taking care not to misalign the direction of compression. Nicked valve stems may result from misalignment of the valve spring compressor.
CAUTION: When depressing the valve spring retainers with valve spring compressor the locks can become dislocated. Ensure both locks are in the correct location after removing tool.
Fig.36:
4. Check the valve spring installed height B after refacing the valve and seat (Fig. 36). Make sure measurements are taken from top of spring seat to the bottom surface of spring retainer. If height is greater than 38.75 mm (1.525 in.), install a 0.762 mm (0.030 in.) spacer under the valve spring seat to bring spring height back within specification.