In Vehicle Service
REMOVAL - CYLINDER HEAD ON1. Disconnect negative battery cable.
2. Remove timing belt.
3. Remove cylinder head cover.
4. Remove camshafts.
5. Rotate crankshaft until piston is at TDC.
6. With air hose attached to adapter tool installed in spark plug hole, apply 90 - 120 psi air pressure.
7. Using Special Tool MD-998772-A with adapter 6779 (Fig. 30), compress valve springs and remove valve locks.
8. Remove valve spring(s).
9. Remove valve stem seal(s) by a using valve stem seal tool (Fig. 32).
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 ON
1. Install valve seal/valve spring seat assembly (Fig. 31). Push the assembly down to seat it onto the valve guide.
2. Install valve spring and retainer, use Special Tool MD-998772-A with adapter 6779 to compress valve springs only enough to install locks (Fig. 30). Correct alignment of tool is necessary to avoid nicking valve stems.
3. Remove air hose and install spark plugs.
4. Install camshafts.
5. Install cylinder head cover.
6. Install timing belt.
7. Connect negative battery cable.