Cylinder Head Assembly: Testing and Inspection
2AZ-FXE ENGINE MECHANICAL: CYLINDER HEAD: INSPECTION
1. INSPECT CYLINDER HEAD FOR WARPAGE
(a) Using a precision straightedge and feeler gauge, measure the warpage of the contact surfaces of the cylinder block sub-assembly and manifolds.
Text in Illustration
Maximum Warpage:
If the warpage is greater than the maximum, replace the cylinder head.
2. INSPECT CYLINDER HEAD FOR CRACKS
(a) Using a dye penetrant, check the intake ports, exhaust ports and cylinder surface for cracks.
If cracked, replace the cylinder head.
3. INSPECT CAMSHAFT THRUST CLEARANCE
(a) Install the camshafts Installation.
(b) Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.
Standard Thrust Clearance:
Maximum Thrust Clearance:
If the thrust clearance is greater than the maximum, replace the cylinder head. If the thrust surface is damaged, replace the camshaft.
4. INSPECT CAMSHAFT OIL CLEARANCE
(a) Clean the bearing caps and camshaft journals.
(b) Place the camshafts on the cylinder head.
(c) Lay a strip of Plastigage across each of the camshaft journals.
Text in Illustration
(d) Install the camshaft bearing caps Installation.
NOTICE:
Do not turn the camshaft.
(e) Remove the camshaft bearing caps Removal.
(f) Measure the Plastigage at its widest point.
Text in Illustration
Standard Oil Clearance:
Maximum Oil Clearance:
NOTICE:
Completely remove the Plastigage after the inspection.
* If the oil clearance is greater than the maximum, replace the camshaft. If necessary, replace the cylinder head.
* If the oil clearance on the camshaft No. 1 journal is greater than the maximum, choose a new bearing and install it.
(1) Check the number mark shown in the illustration.
Text in Illustration
Cylinder Head Journal Bore Diameter:
Bearing Center Wall Thickness:
Camshaft journal diameter:
35.971 to 35.985 mm (1.4162 to 1.4167 in.)
5. INSPECT COMPRESSION SPRING
(a) Using a vernier caliper, measure the free length of the valve spring.
Standard free length:
47.43 mm (1.867 in.)
If the free length is not as specified, replace the valve spring.
(b) Using a steel set square, measure the deviation of the compression spring.
Text in Illustration
Maximum deviation:
1.6 mm (0.0630 in.)
If the deviation is greater than the maximum, replace the compression spring.
6. INSPECT INTAKE VALVE
(a) Using a gasket scraper, scrape off any carbon on the valve head.
(b) Using a wire brush, thoroughly clean the valve.
(c) Using a vernier caliper, measure the overall length of the valve.
Text in Illustration
Standard overall length:
101.71 mm (4.0043 in.)
Minimum overall length:
101.21 mm (3.9846 in.)
If the overall length is less than the minimum, replace the valve.
(d) Using a micrometer, measure the diameter of the valve stem.
Standard valve stem diameter:
5.470 to 5.485 mm (0.2154 to 0.2159 in.)
If the valve stem is not as specified, check the oil clearance.
(e) Using a vernier caliper, measure the valve head margin thickness.
Text in Illustration
Standard margin thickness:
1.05 to 1.45 mm (0.0413 to 0.0571 in.)
Minimum margin thickness:
0.50 mm (0.0197 in.)
If the margin thickness is less than the minimum, replace the valve.
7. INSPECT EXHAUST VALVE
(a) Using a gasket scraper, scrape off any carbon on the valve head.
(b) Using a wire brush, thoroughly clean the valve.
(c) Using a vernier caliper, measure the overall length of the valve.
Text in Illustration
Standard overall length:
101.15 mm (3.9823 in.)
Minimum overall length:
100.70 mm (3.9646 in.)
If the overall length is less than the minimum, replace the valve.
(d) Using a micrometer, measure the diameter of the valve stem.
Standard valve stem diameter:
5.465 to 5.480 mm (0.2152 to 0.2157 in.)
If the valve stem is not as specified, check the oil clearance.
(e) Using a vernier caliper, measure the valve head margin thickness.
Text in Illustration
Standard margin thickness:
1.20 to 1.60 mm (0.0472 to 0.0630 in.)
Minimum margin thickness:
0.50 mm (0.0197 in.)
If the margin thickness is less than the minimum, replace the valve.
8. INSPECT INTAKE VALVE GUIDE BUSH
(a) Using a caliper gauge, measure the inside diameter of the guide bush.
Standard bush inside diameter:
5.510 to 5.530 mm (0.2169 to 0.2177 in.)
(b) Subtract the valve stem diameter measurement from the bush inside diameter measurement.
Standard oil clearance:
0.025 to 0.060 mm (0.000984 to 0.00236 in.)
Maximum oil clearance:
0.080 mm (0.00315 in.)
If the clearance is greater than the maximum, replace the valve and guide bush.
9. INSPECT EXHAUST VALVE GUIDE BUSH
(a) Using a caliper gauge, measure the inside diameter of the guide bush.
Standard bush inside diameter:
5.510 to 5.530 mm (0.2169 to 0.2177 in.)
(b) Subtract the valve stem diameter measurement from the bush inside diameter measurement.
Standard oil clearance:
0.030 to 0.065 mm (0.00118 to 0.00256 in.)
Maximum oil clearance:
0.10 mm (0.00394 in.)
If the clearance is greater than the maximum, replace the valve and guide bush.
10. INSPECT VALVE LIFTER
(a) Using a micrometer, measure the lifter diameter.
Standard lifter diameter:
30.966 to 30.976 mm (1.2191 to 1.2195 in.)
(b) Using a caliper gauge, measure the lifter bore diameter of the cylinder head.
Standard lifter bore diameter:
31.009 to 31.025 mm (1.2208 to 1.2215 in.)
(c) Subtract the lifter diameter measurement from the lifter bore diameter measurement.
Standard oil clearance:
0.033 to 0.059 mm (0.00130 to 0.00232 in.)
Maximum oil clearance:
0.07 mm (0.00276 in.)
If the oil clearance is greater than the maximum, replace the lifter. If necessary, replace the cylinder head.
11. INSPECT CYLINDER HEAD SET BOLT
(a) Using a vernier caliper, measure the length of the cylinder head bolt from the seat to the end.
Text in Illustration
Standard bolt length:
141.3 to 142.7 mm (5.563 to 5.618 in.)
Maximum bolt length:
144.2 mm (5.677 in.)
If the bolt length is greater than the maximum, replace the cylinder head set bolt.