Cylinder Head Assembly
Cylinder HeadCYLINDER HEAD AND CAMSHAFT:
CYLINDER HEAD AND CAMSHAFT:
CYLINDER HEAD AND VALVE ASSEMBLY:
REMOVAL
1. Remove the V-belts.
2. Remove the crank pulley.
3. Remove the timing belt cover.
4. Remove the timing belt.
5. Remove the cam sprocket.
6. Remove the intake manifold.
7. Remove the bolt which installs the A/C compressor bracket on cylinder head.
8. Remove the camshaft.
9. Remove the cylinder head bolts in alphabetical sequence shown in the figure. Leave the bolts (A) and (D) engaged by three or four threads to prevent the cylinder head from falling.
10. While tapping the cylinder head with a plastic hammer, separate it from cylinder block. Remove the bolts (A) and (D) to remove cylinder head.
11. Remove the cylinder head gasket.
CAUTION: Be careful not to scratch the mating surface of cylinder block and cylinder head.
12. Similarly, remove the cylinder head (RH).
INSTALLATION
1. Install the cylinder head and gaskets on cylinder block.
CAUTION:
^ Replace with a new cylinder head gasket.
^ Be careful not to scratch the mating surface of cylinder block and cylinder head.
2. Tighten the cylinder head bolts.
a. Apply a thin coat of engine oil to washer and bolt thread.
b. Tighten all bolts to 29 Nm (3.0 kgf-m, 22 ft. lbs.) in alphabetical sequence.
c. Tighten all bolts to 69 Nm (7.0 kgf-m, 51 ft. lbs.) in alphabetical sequence.
d. Loosen all the bolts by 1800 in the reverse order of tightening, and loosen them again by 180°.
e. Tighten all bolts to 49 Nm (5.0 kgf-m, 36 ft. lbs.) in alphabetical sequence.
f. Tighten all bolts by 80 to 90° in alphabetical sequence.
g. Tighten all bolts by 40 to 45° in alphabetical sequence.
CAUTION: Do not tighten the bolts more than 45°.
h. Further tighten the bolts (A) and (B) by 40 to 45°.
CAUTION: Make sure the total "re-tightening angle" of the previous step (2) does not exceed 90°.
3. Install the camshaft.
4. Install the A/C compressor bracket on cylinder head.
5. Install the intake manifold.
6. Install the cam sprocket.
7. Install the timing belt.
8. Install the timing belt cover.
9. Install the crank pulley.
10. Install the V-belts.
DISASSEMBLY
1. Remove the valve lifter.
2. Compress the valve spring and remove the valve spring retainer key. Remove each valve and valve spring.
ST1 498267600 CYLINDER HEAD TABLE
ST2 499718000 VALVE SPRING REMOVER
NOTE: Keep all the removed parts in order for re-installing in their original positions.
CAUTION:
^ Mark each valve to prevent confusion.
^ Pay careful attention not to damage the lips of intake valve oil seals and exhaust valve oil seals.
ASSEMBLY
1. Installation of valve spring and valve:
a. Coat the stem of each valve with engine oil and insert the valve into valve guide.
NOTE: When inserting the valve into valve guide, use special care not to damage the oil seal lip.
b. Set the cylinder head on ST1.
c. Install the valve spring and retainer using ST2.
ST1 498267600 CYLINDER HEAD TABLE
ST2 499718000VALVE SPRING REMOVER
NOTE: Be sure to install the valve spring with its close-coiled end facing the seat on cylinder head.
d. Compress the valve spring and install the retainer key.
e. After installing, tap the valve spring retainers lightly with a wooden hammer for better seating.
2. Apply oil to the surfaces of the valve lifter.
3. Install the valve lifter.
INSPECTION
1. CYLINDER HEAD
1. Visually check for cracks and damage. Use liquid penetrant tester on the important sections to check for fissures.
2. Measure the warping of the cylinder head surface that mates with crankcase using a straight edge (A) and thickness gauge (B).
If the warping exceeds 0.035 mm (0.0014 inch), regrind the surface with a surface grinder.
Service limit: 0.035 mm (0.0014 inch)
Grinding limit: 0.3 mm (0.012 inch)
Standard height of cylinder head. 127.5 mm (5.02 inch)
NOTE: The cylinder can become warped if the head bolts are tightened at ununiform torques when installing the cylinder head.
2. VALVE SEAT
Inspect the intake and exhaust valve seats, and correct the contact surfaces with a valve seat cutter if they are defective or when valve guides are replaced.
Valve seat width: W
Intake
Standard. 0.6 - 1.4 mm (0.024 - 0.055 inch)
Service limit: 1.7 mm (0.067 inch)
Exhaust
Standard. 1.2 - 1.8 mm (0.047 - 0.071 inch)
Service limit: 2.2 mm (0.087 inch)
3. VALVE GUIDE
1. Check the clearance between valve guide and stem. The clearance can be checked by measuring respectively the outer diameter of valve stem with a micrometer and the inner diameter of valve guide with a caliper gauge. Clearance between the valve guide and valve stem:
Standard.
Intake 0.030 - 0.057 mm (0.0012 - 0.0022 inch)
Exhaust 0.040 - 0.067 mm (0.0016 - 0.0026 inch)
Service limit. 0.15 mm (0.0059 inch)
2. If the clearance between valve guide and valve stem exceeds the limit, replace the valve guide or valve itself whichever shows greater amount of wear. See the following procedure for valve guide replacement.
Valve guide inner diameter. 6.000 - 6.012 mm (0.2362 - 0.2367 inch)
Valve stem outer diameters:
Intake 5.955 - 5.970 mm (0.2344 - 0.2350 inch)
Exhaust 5.945 - 5.960 mm (0.2341 - 0.2346 inch)
a. Place the cylinder head on ST1 with the combustion chamber upward so that valve guides fit the holes in ST1.
b. Insert the ST2 into valve guide and press it down to remove the valve guide.
ST1 498267600 CYLINDER HEAD TABLE
ST2 499767200 VALVE GUIDE REMOVER
c. Turn the cylinder head upside down and place the ST as shown in the figure.
ST 18251AA020 VALVE GUIDE ADJUSTER
d. Before installing a new valve guide, make sure that neither scratches nor damages exist on the inner surface of valve guide holes in cylinder head.
e. Put a new valve guide, coated with sufficient oil, in the cylinder head, and insert the ST1 into valve guide. Press in until the valve guide upper end is flush with the upper surface of ST2.
ST1 499767200 VALVE GUIDE REMOVER
ST2 18251AA020 VALVE GUIDE ADJUSTER
f. Check the valve guide protrusion.
Valve guide protrusion: 15.8 - 16.2 mm (0.622 - 0.638 inch)
g. Insert the ST in valve guide, and rotate the ST slowly clockwise while pushing it lightly. Bring the ST back while rotating it clockwise. (Reaming Work)
h. After reaming, clean the valve guide to remove chips.
ST 499767400 VALVE GUIDE REAMER
CAUTION: Apply engine oil to the ST when reaming.
NOTE:
^ If the inner surface of valve guide is damaged, the edge of ST should be slightly ground with oil stone.
^ If the inner surface of valve guide becomes lustrous and the ST does not chip, use a new ST or remedy the ST.
i. Recheck the contact condition between valve face and valve seat after replacing the valve guide.
4. INTAKE AND EXHAUST VALVE
1. Inspect the flange and stem of valve, and replace if damaged, worn, or deformed. If "H" is less than the specified limit, replace with a new valve. H.
Intake (A)
Standard. 1.0 - 1.4 mm (0.039 - 0.055 inch)
Service limit. 0.8 mm (0.031 inch)
Exhaust (B)
Standard. 1.3 - 1.7 mm (0.057 - 0.067 inch)
Service limit. 0.8 mm (0.031 inch)
2. Put a small amount of grinding compound on the seat surface, and lap the valve and valve seat.
NOTE:
^ Replace with a new valve oil seal after lapping.
^ It is possible to differentiate between the intake valve and the exhaust valve by their overall length.
Valve overall length:
Intake (A) 104.4 mm (4.110 inch)
Exhaust (B) 104.65 mm (4.120 inch)
5. VALVE SPRING
1. Check the valve springs for damage, free length, and spring constant. Replace the valve spring if it is not within standard values presented in the table.
2. To measure the squareness of the valve spring, stand the spring on a surface plate and measure its deflection at the top of spring using a try square.
6. INTAKE AND EXHAUST VALVE OIL SEAL
1. For the following, replace the oil seal with a new one.
2. See the procedure and subsequent for replacement procedures.
^ When the lip is damaged.
^ When the spring is out of the specified position.
^ When readjusting the surfaces of intake valve and valve sheet.
^ When replacing the intake valve guide.
2. Place the cylinder head on ST1.
3. Press-fit the oil seal to the specified dimension indicated in the figure using ST2.
ST1 498267600 CYLINDER HEAD TABLE
ST2 498857100 VALVE OIL SEAL GUIDE
CAUTION:
^ Apply engine oil to oil seal before press-fitting.
^ When press-fitting the oil seal, do not use a hammer or strike in.
^ Note that the intake valve oil seal and exhaust valve oil seal are differentiated by colors.
Color of rubber part.
Intake [Gray]
Exhaust [Green]
7. VALVE LIFTER
1. Check the valve lifter visually.
2. Measure the outer diameter of valve lifter.
Outer diameter. 34.959 - 34.975 mm (1.3763 - 1.3770 inch)
3. Measure the inner diameter of valve lifter mating surface on cylinder head.
Inner diameter. 34.994 - 35.016 mm (1.3777 - 1.3786 inch)
NOTE: If difference between outer diameter of valve lifter and inner diameter of valve lifter mating part is over the limit, replace the cylinder head.
Standard. 0.019 - 0.057 mm (0.0007 - 0.0022 inch)
Service limit: 0.100 mm (0.0039 inch)
DISPOSAL
CAUTION:
^ Metallic sodium is enclosed in the exhaust valve. Metallic sodium is extremely alkaline and may produce severe chemical reactions. Full consideration must be therefore be given to the following points when handling or disposing of the valve.
^ Since metallic sodium may cause blindness if contacted with the eyes, burns if contacted with the skin, and fire, do not deliberately take the valve apart.
1. If the valve is damaged, remove the valve and neutralize it by immersing it in water, and dispose of it in the same way that general steel materials are disposed of. The disposal method is described in the following.
a. Wearing rubber gloves, remove the damaged valve from the cylinder head.
b. Prepare a large receptacle (bucket or other container) in a well ventilated location, and fill the receptacle with water. (at least 10 liters)
c. Immerse the damaged valve in the receptacle.
CAUTION: A severe reaction may occur, so stand at least 2 - 3 m from the receptacle. Because the reaction will produce hydrogen gas, moreover, keep the receptacle away from sparks or flames.
d. Once the reaction is completed (about 4 - 5 hours have elapsed), carefully remove the valve using large pincers so that the reaction liquid does not contact your skin, and dispose of it with other parts that are being disposed of.
e. The reaction liquid is a strong alkaline solution, so it must be disposed of in accordance with local regulations.
CAUTION: Make sure the reaction liquid does not contact your skin. If contact with skin occurs, immediately wash the affected area with large quantities of water.
