If the cylinder head is removed from the engine, refer to the valve removal and installation procedures in this section and remove the valve springs.
REMOVAL & INSTALLATION
See Figures 1 through 6
- Refer to the rocker arm removal and installation procedures in this section and remove the rocker arm assembly.
- Using an old set of rocker arm shafts, install them in place of the rocker arm assembly; this will prevent bending or scratching the original set of shafts.
- Remove the spark plug(s) from the cylinder head.
- Rotate the crankshaft to position the cylinder (being worked on) to the TDC of its compression stroke.
- Using a Spark Plug Air Hold tool, install it into the spark plug hole and inject compressed air into the cylinder to hold the valves in place.
- Using a valve spring compressor tool, compress the spring(s) and remove the valve keepers. Relax the spring compressor tool, then remove the valve retainer, the spring(s) and the valve seal; keep the parts in the exact order for reinstallation purposes.
If reusing the valve seals, it is recommended to replace the neck springs of the seal; the black spring is used on the exhaust valve seal and the white spring is used on the intake valve seal. The seals are not interchangeable between the intake and the exhaust valves.
- Inspect the springs for fatigue, cracks and/or uniformity; if necessary, replace them.
- To assemble, first lubricate the valves with clean engine oil and slide the valves up and down in the valve guides to make sure they move smoothly.
- Install the valve seals using a valve guide seal installer or suitable tool
- Then install the seals and lubricate the parts with clean engine oil. Use the valve spring compressor tool to compress the springs and carefully install the valve keepers, retainers and springs.
- After removing the valve spring compressor, tap the valve stems with a plastic mallet 2-3 times to make sure the valve keepers and valves are fully seated. Only tap each valve stem along its axis so you do not bend it.
- Refer to the rocker arms/shafts and camshaft installation procedures in this section, then reassemble the rest of the cylinder head.
When installing the springs, be sure to position the closely wound coil ends or painted part toward the cylinder head.
- To complete the installation, use new gaskets and install the cylinder head on the vehicle.
- Refill the cooling system, connect the negative battery terminal, start the engine and check for normal running and leaks.
- Position the valve spring on a flat, clean surface next to a square.
- Rotate the spring against the square to measure the distortion (out-of-roundness). If the spring height varies (between similar springs) by more than 1/16 in. (1.6mm), replace the spring.