Cylinder Head

CYLINDER HEAD ASSEMBLY (2AZ-FE)
OVERHAUL
1. REMOVE VALVE LIFTER

HINT: Arrange the valve lifters in the correct order.

2. REMOVE INTAKE VALVE
a. Place the cylinder head on wooden blocks.
b. Using SST, compress the spring, then remove the 2 retainer locks.
SST 09202-70020 (09202-00010)
c. Remove the retainer, spring and valve from the cylinder head.

HINT: Arrange the removed parts in the correct order.

3. REMOVE EXHAUST VALVE
a. Place the cylinder head on wooden blocks.
b. Using SST, compress the spring, then remove the 2 retainer locks.
SST 09202-70020 (09202-00010)
c. Remove the retainer, spring and valve from the cylinder head.

HINT: Arrange the removed parts in the correct order.

4. REMOVE VALVE STEM OIL O SEAL OR RING
a. Using needle-nose pliers, remove the 16 oil seals.
5. REMOVE VALVE SPRING SEAT

6. REMOVE STUD BOLT
a. Using torx socket wrenches E5 and E7, remove the 11 stud bolts.

7. CHECK CYLINDER HEAD FOR WARPAGE
a. Using a precision straight edge and a feeler gauge, measure the surface that is in contact with the cylinder block and the manifolds for warpage.
Maximum warpage: 0.08 mm (0.0032 inch)
If the warpage is greater than maximum, replace the cylinder head.

8. CHECK CYLINDER HEAD FOR CRACKS
a. Using a dye penetrate, check the combustion chamber, intake ports, exhaust ports and cylinder block surface for cracks.
If cracked, replace the cylinder head.
9. INSPECT VALVE SEATS
a. Apply a light coat of Prussian blue (or white lead) to the valve face.
b. Lightly press the valve against the seat.

NOTICE: Do not turn the valve.

c. Check the valve face and seat in accordance with the following procedure.
1. If blue appears 360° around the face, the valve is concentric. If not, replace the valve.
2. If blue appears 360° around the valve seat, the guide and face are concentric. If not, resurface the seat.
3. Check that the seat contact is in the middle of the valve face with a width of between 1.0 to 1.4 mm (0.039 to 0.055 inch).
10. REPAIR VALVE SEATS

NOTICE: Releasing the seat cutter pressure gradually helps to make the valve seat faces smoother.

a. If the seating is too high on the valve face, use 30° and 45° cutters to correct the seat.

b. If the seating is too low on the valve face, use 75° and 45° cutters to correct the seat.
c. Lap the valve and valve seat by hand with an abrasive compound.
d. Recheck the valve seating position.

11. CHECK CAMSHAFT THRUST CLEARANCE
a. Install the 2 camshafts.
b. Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.
Standard thrust clearance:
0.040 to 0.095 mm (0.0016 to 0.0037 inch) for intake
0.080 to 0.135 mm (0.0032 to 0.0053 inch) for exhaust
Maximum thrust clearance:
0.110 mm (0.0043 inch) for intake
0.150 mm (0.0059 inch) for exhaust
- If the thrust clearance is greater than maximum, replace the cylinder head.
- If damages are found on the camshaft thrust surfaces, replace the camshaft.

12. CHECK CAMSHAFT OIL CLEARANCE
a. Clean the 10 bearing caps and camshaft journals.
b. Place the 2 camshafts on the cylinder head.
c. Lay a strip of Plastigage across each of the camshaft journal.
d. Install the 10 bearing caps.

NOTICE: Do not turn the camshaft.

e. Remove the 10 bearing caps.

f. Measure the Plastigage at its widest point.

Standard oil clearance

Maximum clearance

NOTICE: Completely remove the Plastigage after the measurement.

If the oil clearance is greater than maximum, replace the cylinder head or the camshaft.

If the oil clearance on the No.1 journal is greater than maximum, choose a new bearing and install it.

HINT:

Cylinder head journal bore diameter

Standard bearing center wall thickness

Camshaft journal diameter: 35.971 to 35.985 mm (1.4162 to 1.4167 inch)

13. INSPECT VALVE LIFTER
a. Using a micrometer, measure the lifter diameter.
Lifter diameter: 30.966 to 30.976 mm (1.2191 to 1.2195 inch)
If the diameter is not as specified, replace the valve lifter.

14. CHECK VALVE LIFTER OIL CLEARANCE
a. Using a caliper gauge, measure the valve lifter bore diameter of the cylinder head.
Lifter bore diameter: 31.009 to 31.025 mm (1.2208 to 1.2215 inch)
If the diameter is not as specified, replace the cylinder head.
b. Subtract the valve lifter diameter measurement from the valve lifter bore diameter measurement.
Standard oil clearance: 0.033 to 0.059 mm (0.0013 to 0.0023 inch)
Maximum oil clearance: 0.079 mm (0.0031 inch)
- If the oil clearance is greater than maximum, replace the valve lifter.
- If necessary, replace the cylinder head.

15. INSPECT INNER COMPRESSION SPRING
a. Using vernier calipers, measure the free length of the valve spring.
Free length: 45.7 mm (1.799 inch)
If the length is not as specified, replace the compression spring.

b. Using a steel square, measure the deviation of the inner compression spring.
Maximum deviation: 1.6 mm (0.063 inch)
Maximum angle (Reference): 2°
If the deviation is greater than maximum, replace the compression spring.

16. INSPECT INTAKE VALVE
a. Using vernier calipers, measure the valve overall length.
Standard overall length: 101.71 mm (4.0043 inch)
Minimum overall length: 101.21 mm (3.9846 inch)
If the overall length is less than minimum, replace the valve.

b. Using a micrometer, measure the diameter of the valve stem.
Valve stem diameter: 5.470 to 5.485 mm (0.2154 to 0.2159 inch)
If the diameter is not as specified, replace the valve.

c. Using vernier calipers, measure the valve head margin thickness.
Standard margin thickness: 1.0 mm (0.039 inch)
Minimum margin thickness: 0.50 mm (0.0197 inch)
If the margin thickness is less than minimum, replace the valve.

17. INSPECT EXHAUST VALVE
a. Using vernier calipers, measure the valve overall length.
Standard overall length: 101.15 mm (3.9823 inch)
Minimum overall length: 100.70 mm (3.9646 inch)
If the overall length is less than minimum, replace the valve.

b. Using a micrometer, measure the diameter of the valve stem.
Valve stem diameter: 5.465 to 5.480 mm (0.2152 to 0.2158 inch)
If the diameter is not as specified, replace the valve.

18. INSPECT VALVE GUIDE BUSH OIL CLEARANCE
a. Using a caliper gauge, measure the inside diameter of the valve guide bush.
Bush inside diameter: 5.510 to 5.530 mm (0.2169 to 0.2177 inch)
If the inside diameter is not as specified, replace the valve guide bush.
b. Subtract the valve stem diameter measurement from the guide bush inside diameter measurement.

Standard oil clearance

Maximum oil clearance

If the oil clearance is greater than maximum, replace the valve and valve guide bush.

19. REMOVE INTAKE VALVE GUIDE BUSH
a. Using SST, tap out the guide bush.
SST 09201-10000 (09201-01050), 09950-70010 (09951-07100)

20. REMOVE EXHAUST VALVE GUIDE BUSH
a. Using SST, tap out the guide bush.
SST 09201-10000 (09201-01050), 09950-70010 (09951-07100)
21. INSTALL INTAKE VALVE GUIDE BUSH
a. Using a caliper gauge, measure the bush bore diameter of the cylinder head.
Diameter: 10.285 to 10.306 mm (0.4049 to 0.4058 inch)
b. Install the STD bush if the diameter is within the specified diameter.
Standard diameter: 10.333 to 10.344 mm (0.4068 to 0.4072 inch)

c. Using SST, tap in a new guide bush to the specified protrusion height.
SST 09201-10000 (09201-01050), 09950-70010 (09951-07100)
Protrusion height: 9.6 to 10 mm (0.3780 to 0.3937 inch)
d. Using a sharp 5.5 mm reamer, ream the valve guide bush to the standard specified clearance between the valve guide bush and valve stem.
Standard oil clearance: 0.025 to 0.060 mm (0.0010 to 0.0024 inch)
22. INSTALL EXHAUST VALVE GUIDE BUSH
a. Using a caliper gauge, measure the bush bore diameter of the cylinder head.
Diameter: 10.285 to 10.306 mm (0.4049 to 0.4058 inch)
b. Install the STD bush if the diameter is within the specified diameter.
Standard diameter: 10.333 to 10.344 mm (0.4068 to 0.4072 inch)

c. Using SST, tap in a new guide bush to the specified protrusion height.
SST 09201-10000 (09201-01050), 09950-70010 (09951-07100)
Protrusion height: 9.6 to 10.0 mm (0.3780 to 0.3937 inch)
d. Using a sharp 5.5 mm reamer, ream the valve guide bush to the standard specified clearance between the valve guide bush and valve stem.
Standard oil clearance: 0.030 to 0.065 mm (0.0012 to 0.0026 inch)

23. INSTALL RING W/HEAD PIN
a. Using a plastic faced hammer, tap in new 4 ring pins to the specified protrusion height.
Protrusion height: 3.0 mm (0.12 inch)

24. INSTALL STUD BOLT
a. Using torx socket wrenches E5 and E7, install the 11 stud bolts.
Torque:
5.0 Nm (51 kgf-cm, 44 inch lbs.) for bolt A
5.0 Nm (51 kgf-cm, 44 inch lbs.) for bolt B
9.5 Nm (97 kgf-cm, 84 inch lbs.) for bolt C
9.5 Nm (97 kgf-cm, 84 inch lbs.) for bolt D
25. INSTALL VALVE SPRING SEAT

26. INSTALL VALVE STEM OIL O SEAL OR RING
a. Apply a light coat of engine oil to a new oil seals.

NOTICE: Pay close attention when installing the intake and exhaust oil seals. Mixing up the two seals can cause installation problems.

HINT: The intake valve stem oil seal is gray and exhaust valve stem oil seal is black.

b. Using SST, push in the 16 oil seals by hand.
SST 09201-41020

27. INSTALL INTAKE VALVE
a. Place the cylinder head on wooden blocks.
b. Install the valve, spring and retainer onto the cylinder head.
c. Using SST, compress the spring, and place the 2 retainer locks around the valve stem.
SST 09202-70020 (09202-00010)

d. Using a plastic faced hammer and discarded valve (its tip is wrapped with tape), lightly tap the installed valve to fit into place.

NOTICE: Be careful not to damage the valve stem tip.

28. INSTALL EXHAUST VALVE
a. Place the cylinder head on wooden blocks.
b. Install the valve, spring and retainer onto the cylinder head.
c. Using SST, compress the spring, and place the 2 retainer locks around the valve stem.
SST 09202-70020 (09202-00010)

d. Using a plastic faced hammer and discarded valve (its tip is wrapped with tape), lightly tap the installed valve to fit into place.

NOTICE: Be careful not to damage the valve stem tip.

29. INSTALL VALVE LIFTER
a. Assemble the valve lifter and the tip of the valve stem with a light coat of engine oil applied.

NOTICE: Install the valve lifters in their original places.