Disassembly

CYLINDER HEAD

Components:

DISASSEMBLY
1. REMOVE VALVE LIFTER
a. Remove the valve lifter and adjusting shim.

HINT: Arrange the valve lifters and shims in the correct order.

2. REMOVE INTAKE VALVE
a. Using SST, compress the compression spring and remove the 2 keepers.
SST 09202-70020 (09202-00010)
b. Remove the spring retainer, compression spring, valve and spring seat.

HINT: Arrange the valves, compression springs, spring seats and spring retainers in the correct order.

3. REMOVE EXHAUST VALVE
a. Using SST, compress the compression spring and remove the 2 keepers.
SST 09202-70020 (09202-00010)
b. Remove the spring retainer, compression spring, valve and spring seat.

HINT: Arrange the valves, compression springs, spring seats and spring retainers in the correct order.

4. REMOVE VALVE STEM OIL SEAL
a. Using needle nose pliers, remove the oil seal.

5. REMOVE CAMSHAFT TIMING TUBE ASSEMBLY
a. Mount the hexagon head portion of the camshaft in a vise.

NOTICE:
^ Be careful not to damage the camshaft.
^ Do not remove the 4 bolts shown in the illustration. The bolts determine the backlash of the gear in the timing tube. If any of the bolts are removed, install a new timing tube assembly.

b. Remove the screw plug and seal washer.

c. Using a 10 mm hexagon wrench, remove the bolt.
d. Pullout the timing tube and drive gear from the camshaft.

e. Using SST and a 5 mm hexagon wrench, remove the 4 bolts, drive gear and oil seal.
SST 09960-10010 (09962-01000, 09963-00500)

NOTICE: Be careful not to damage the timing tube.

6. REMOVE CAMSHAFT SUB GEAR
a. Mount the hexagon head portion of the camshaft in a vise.

NOTICE: Be careful not to damage the camshaft.

b. Using SST, turn the sub gear clockwise and remove the service bolt.
SST 09960-10010 (09962-01000, 09963-00500)

c. Using snap ring pliers, remove the snap ring.
d. Remove the wave washer, sub gear and bolt washer.

HINT: Arrange the driven sub gears and bolt washers (RH and LH sides).

e. Using a vernier caliper, measure the free distance between the washer ends.
Free distance: 18.2 to 18.8 mm (0.712 to 0.740 inch)
If the free distance is not as specified, replace the washer.

REPLACEMENT

1. REMOVE INTAKE VALVE GUIDE BUSH
a. Gradually heat the cylinder head to approximately 80 to 100°C (176 to 212°F).

b. Using SST and a hammer, tap out the guide bush.
SST 09201-01055, 09950-70010 (09951-07100)

2. INSTALL INTAKE VALVE GUIDE BUSH
a. Using a caliper gauge, measure the bush bore diameter of the cylinder head.

b. Select a new guide bush (STD or O/S 0.05).

Bush Bore Diameter:

HINT:
^ If the bush bore diameter of the cylinder head is greater than 10.306 mm (0.4057 inch), machine the bush bore diameter to between 10.335 and 10.356 mm (0.4068 to 0.4077 inch).
^ If the bush bore diameter of the cylinder head is greater than 10.356 mm (0.4077 inch), replace the cylinder head.

HINT: Different bushes are used for the intake and exhaust.

Intake bush length: 34.5 mm (1.358 inch)

c. Gradually heat the cylinder head to approximately 80 to 100°C (176 to 212°F).
d. Using SST and a hammer, tap in a new guide bush to the specified protrusion height.
SST 09201-01055, 09950-70010 (09951-07100)
Protrusion height (H): 9.2 to 9.8 mm (0.362 to 0.386 inch)

e. Using a sharp 5.5 mm reamer, ream the guide bush to obtain the standard specified clearance between the guide bush and valve stem.

3. REMOVE EXHAUST VALVE GUIDE BUSH
a. Gradually heat the cylinder head to approximately 80 to 100°C (176 to 212°F).

b. Using SST and a hammer, tap out the guide bush.
SST 09201-01055, 09950-70010 (09951-07100)

4. INSTALL EXHAUST VALVE GUIDE BUSH
a. Using a caliper gauge, measure the bush bore diameter of the cylinder head.
b. Select a new guide bush (STD or O/S 0.05).

Bush Bore Diameter:

HINT:
^ If the bush bore diameter of the cylinder head is greater than 10.306 mm (0.4057 inch), machine the bush bore diameter to between 10.335 and 10.356 mm (0.4068 to 0.4077 inch).
^ If the bush bore diameter of the cylinder head is greater than 10.356 mm (0.4077 inch), replace the cylinder head.

HINT: Different bushes are used for the intake and exhaust.

Exhaust bush length: 40.5 mm (1.594 inch)

e. Using a sharp 5.5 mm reamer, ream the guide bush to obtain the standard specified clearance between the guide bush and valve stem.