See Figure 1
The following procedures to be performed with cylinder head removed from engine.
- Compress the valve springs using Tool C-3422A or equivalent. Do not mix the removed parts. Place the parts from each valve in a separate container, numbered and identified for the valve and cylinder.
- Remove the valve retaining locks, valve spring retainers, valve stem seal, valve springs and valve spring seats from the valve stem.
Before removing valve assembly remove any burrs from valve stem lock grooves to prevent damage to valve guides.
- Remove the valve assembly.
See Figure 2
- Clean valves thoroughly.
- Check valve stem tip for pitting or depression.
- Check for ridge wear on valve stem area.
- Inspect valve (with Prussian blue) for even contact between valve face and cylinder head valve seat.
- Gently remove valve stem seals with a pliers or screwdriver by prying side-to-side. Do not reused old seals.
- Remove carbon and varnish deposits from inside of valve guides of cylinder head with a suitable guide cleaner.
- Use an electric drill and soft rotary wire brush to clean the intake and exhaust valve ports, combustion chamber and valve seats. In some cases, the carbon build-up will have to be chipped away. Use a blunt pointed drift for carbon chipping, be careful around valve seat areas.
When using a wire brush to clean carbon on the valve ports, valves, etc., be sure the deposits are actually removed, rather then burnished.
- Wash and clean all valve spring, locks, retainers and other related components in safe solvent. Remember to keep parts from each valve separate.
If valve guide replacement is necessary, or valve or seat refacing is necessary, the job must be handled by a qualified machine shop.If a valve seat is damaged, burnt or loose, the seat may be resurfaced or replaced as necessary. The automotive machine shop can handle the job for you.
CHECKING VALVE SPRINGS
See Figures 3, 4 and 5
Place the valve spring on a flat surface next to a carpenters square. Measure the height of the spring, and rotate the spring against the edge of the square to measure distortion. If the spring height varies (by comparison) by more than 1 / 16 in. (1.58mm) or if the distortion exceeds 1 / 16 in. (1.58mm), replace the spring.
Have the valve springs tested for spring pressure at the installed and compressed (installed height minus valve lift) height using a valve spring tester. Springs should be within one pound, plus or minus of each other. Replace the springs as necessary.
See Figure 6
- Coat valve stems with lubrication oil and install in cylinder head.
- Install a new valve stem seal on the valve. The valve stem seal should be install firmly and squarely over the valve guide.' The lower edge of the seal should rest on the valve guide boss.
- Install the valve spring seat, valve spring, and retainer.
- Using Tool C-3422A, or equivalent, compress the valve spring only far enough to install the retainer locks. Install the retainer locks and make certain that the locks are in their correct location before removing the valve compressor.
- Repeat Steps 1-4 on the remaining valves.