Disassembly and Reassembly
CYLINDER HEAD
COMPONENTS
DISASSEMBLY
1. Remove the engine.
2. Refer to intake manifold.
3. Remove the cables from the spark plugs. The cables should be removed by holding the boot portion.
4. Remove the ignition coil.
5. Remove the upper and lower timing belt cover.
6. Remove the timing belt and camshaft sprockets.
7. Remove the heat protector and exhaust manifold assembly.
8. Remove the coolant pump pulley and head cover.
9. Remove the intake and exhaust camshaft.
10. Remove the cylinder head assembly. The cylinder head bolts should be removed using the 12 mm socket, in two or three steps.
11. Clean the gasket pieces from the cylinder block top surface and cylinder head bottom surface.
NOTE: Make sure that fragments from the gasket do not fall in the engine.
RETAINER LOCK
1. Compress the valve spring using special tool. (09222 - 28000, 09222 - 28100)
2. Remove the retainer lock.
3. Remove the valve spring, valve spring retainer valve spring sheet and valve.
INSPECTION
CYLINDER HEAD
1. Remove scale, sealing compound and carbon deposits. After cleaning oil passages, apply compressed air to make certain that the passages are not clogged.
2. Visually check the cylinder head for cracks, damage or water leakage.
3. Check the cylinder head surface for flatness with a straight edge and feeler gauge as shown in the illustration.
Cylinder head flatness
Standard dimensions: Max. 0.03 mm (0.0059 inch)
Service limit: 0.05 mm (0.0020 inch)
VALVE GUIDES
Check the valve stem - to - guide clearance. If the clearance exceeds the service limit, replace the valve guide with a new oversize guide.
Valve stem-to-guide clearance
Standard value
Intake: 0.02 - 0.05 mm (0.0009 - 0.0020 inch)
Exhaust: 0.050 - 0.085 mm (0.0020 - 0.0033 inch)
VALVE
1. Replace the valve if its stem is bent, worn or damaged. Also replace it if the stem end (the surface contacting the hydraulic-lash adjuster) is hollowed out.
2. Check the valve face contact area, and recondition or replace as necessary.
3. Replace the valve if the width of the margin (thickness of the valve head) is less than the minimum specified.
Valve margin
Standard value
Intake: 1.0 mm (0.0394 inch)
Exhaust: 1.3 mm (0.0512 inch)
VALVE SPRING
1. Check the free height of each valve spring and replace if necessary.
2. Using a square, test the squareness of each valve spring. If the spring is excessively out-of-square, replace it.
Valve spring
Standard value
Free height: 46.4 mm (1.8268 inch)
Load: 24 kg /37.9 mm (53 lbs./1.492 inch)
Out - of - square: Max. 2°
Service limit
Free height: 0.45.4 mm (1.787 inch)
Out - of - square: Max. 4°
REPLACING VALVE GUIDE
1. Using the special tool (09222-22000B), withdraw the old valve guide out the bottom of the cylinder head.
2. Recondition the valve guide hole so that it can receive the newly press-fitted oversize valve guide.
VALVE GUIDE OVERSIZES
3. Using the special tool (09221-29000(A), 09222 22000(B)) press-fit the valve guide. The valve guide must be press-fitted from the upper side of the cylinder head. Keep in mind that the intake and exhaust valve guides are different in length.
4. After the valve guide is press-fitted, insert a new valve and check for proper clearance.
5. After the valve guide is replaced, check that the valve is fully seated. Recondition the valve seats as necessary.
NOTE: Do not install a valve guide valves it is oversize.
REPLACING VALVE SEAT RING
1. Cut away the inner face of the valve seat to reduce the wall thickness.
2. Enlarge the diameter of the valve seat so that it matches the specified hole diameter of the new valve seat ring.
VALVE SEAT RING OVERSIZES
3. Heat the cylinder head to about 250°C (480°F) and press-fit an oversize seat ring for the bore in the cylinder head.
4. Using lapping compound, lap the valve to the new seat.
Valve seat contact width
Intake: 0.9 - 1.3 mm (0.035 - 0.051 inch)
Exhaust: 0.9 - 1.3 mm (0.035 - 0.051 inch)
REASSEMBLY
1. Install the spring seats.
2. Using special tool (09222 - 28200), lightly tap the seal in position.
NOTE:
^ Do not reuse old valve stem seals.
^ Incorrect installation of the seal could result in oil leakage of from the valve guides.
3. Apply engine oil to each valve. Insert the valve into their guides. Avoid pushing the valve into the seal by force. After installing the valve,check that it moves smoothly.
4. Place valve springs so that the side coated with enamel faces toward the valve spring retainer.
5. Using the special tool (09222-28000, 09222-28100), compress the spring and install the retainer locks. After installing the valves, ensure that the retainer locks are correctly in place before releasing the valve-spring compressor.
NOTE: When the spring is compressed, check that the valve stem seal is not pressed against the bottom of the retainer.
6. Clean both gasket surfaces of the cylinder head and cylinder block.
7. Verify the identification marks on the cylinder head gasket.
8. Install the gasket so that the surface with the identification mark faces toward the cylinder head.
NOTE: Do not apply sealant to these surfaces.
9. Tighten the cylinder head bolts in the sequence shown in the illustration with a torque wrench.
10. Tighten the cylinder head bolts. Starting at top center, tighten all cylinder head bolts in sequence as shown in the illustration, using the 12 mm socket.
Tightening procedure
Cylinder head bolt: 105 - 115 Nm (1050 - 1 150 kg-cm, 75 - 82 ft. lbs.)