REMOVAL & INSTALLATION
- Remove the cylinder head.
- On the 2.2L engine, remove the rocker arms/shafts assemblies and the camshaft.
- Block the head on its side, or install a pair of head-holding brackets made especially for valve removal.
- Use a socket slightly larger than the valve stem and keepers, place the socket over the valve stem and gently hit the socket with a plastic hammer to break loose any varnish buildup.
- Remove the valve keepers, retainer, and valve spring using a valve spring compressor (the locking C-clamp type is the easiest to use).
- Place the parts from each valve in a separate container, numbered and identified for the valve and cylinder.
- Remove and discard the valve stem oil seal, a new seal will be used at assembly time.
- Remove the valves from the cylinder head and place, in order, through holes punched in a stiff piece of cardboard.
- Use an electric drill and 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, being careful around valve seat areas.
- Use a valve guide cleaning brush and safe solvent to clean the valve guides.
- Clean the valves with a revolving wire brush. Heavy carbon deposits may be removed with blunt drift.
When using a wire brush to remove carbon from the cylinder head or valves, make sure the deposits are actually removed and not just burnished.
- Wash and clean all valve springs, keepers, retainers etc., in safe solvent. Remember to keep parts from each valve separate.
- Check the cylinder head for cracks. Cracks usually start around the exhaust valve seat because it is the hottest part of the combustion chamber. If a crack is suspected but cannot be detected visually, have the area checked by pressure testing, with a dye penetrant or other method by an automotive machine shop.
- Inspect the valves, guides, springs and seats and machine or replace parts, as necessary.
- On the 2.2L engine, install new valve seals with valve seal installer tool T87C-6510-B or equivalent. Dip each valve in clean engine oil and install in its original location.
- On the 3.0L engine, dip each valve in clean engine oil and install in its original location. Install new valve seals, using a 5 / 8 in. deep-well socket and a light mallet to seat the seal on the cylinder head and valve stem.
- Install any required shims, the valve spring and the retainer over the valve stem. Compress the spring with the valve spring compressor and install the keepers.
- After all the valves and springs have been assembled, take a mallet and lightly strike each valve stem tip squarely to seat the keepers.
- On the 2.2L engine, install the camshaft and the rocker arm/shaft assemblies.
- Remove the valves from the cylinder head. Clean the valves, valve guides, valve seats and related components, as explained earlier.
- Visually check the valves for obvious wear or damage. A burnt valve will have discoloration, severe galling or pitting and even cracks on one area of the valve face. Minor pits, grooves, etc. can be removed by re-facing. Check the valve stems bends and for obvious wear that is indicated by a step between the part of the stem that travels in the valve guide and the part of the stem near the keeper grooves.
- Check the valve stem-to-guide clearance. If a dial indicator is not on hand, a visual inspection can give you a fairly good idea if the guide, valve stem or both are worn. Insert the valve into the guide until the valve head is slightly away from the valve seat. Wiggle the valve sideways. A small amount of wobble is normal, excessive wobble means a worn guide and/or valve stem. If a dial indicator is on hand, mount the indicator so that gauge stem is 90° to the valve stem as close to the top of the valve guide as possible. Move the valve from the seat, and measure the valve guide-to-stem clearance by rocking the stem back and forth to actuate the dial indicator. Measure the valve stem using a micrometer and compare to specifications to determine whether stem or guide is causing excessive clearance.
- The valve guide, if worn, must be repaired before the valve seats can be resurfaced. A new valve guide should be installed or, in some cases, knurled. Consult the automotive machine shop.
- If the valve guide is okay, measure the valve seat concentricity using a runout gauge. Follow the manufacturers instructions. If runout is excessive, reface or replace the valve and machine or replace the valve seat.
- Valves and seats must always be machined together. Never use a refaced valve on a valve seat that has not been machined; never use a valve that has not been refaced on a machined valve seat.
- Determine if the valve is usable as explained in the Inspection procedure.
- Refer to specifications for the correct valve face machining angle. Make sure the valve re-facer grinding wheels are properly dressed.
- Reface the valve face only enough to remove the pits and grooves or correct any runout. If the edge of the valve head is less than 32 in. (0.8mm) thick after grinding, replace the valve, as the valve will run too hot in the engine.
- Remove all grooves or score marks from the end of the valve stem, and chamfer it, as necessary. Do not remove more than 0.010 in. (0.254mm) from the end of the valve stem.
- When the engine is reassembled, it will be necessary to check the clearance between the rocker arm pad and the valve stem tip. Refer to .