Cylinder Head Assembly: Testing and Inspection
2ZR-FE ENGINE MECHANICAL: CYLINDER HEAD: INSPECTION
1. INSPECT CYLINDER HEAD FOR FLATNESS
(a) Using a precision straight edge and a feeler gauge, measure the surface contacting the cylinder block and the manifolds for warpage.
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 VALVE SEATS
(a) Apply a light coat of Prussian Blue to the valve face.
(b) Lightly press the valve face against the valve seat.
(c) Check the valve face and valve seat according to the following procedure:
(1) If Prussian Blue appears 360° around the valve face, the valve face is concentric. If not, replace the valve.
(2) If Prussian Blue appears 360° around the valve seat, the guide and valve face are concentric. If not, resurface the valve seat.
(3) Check that the valve seat contact is in the middle of the valve face with the valve seat width between 1.0 and 1.4 mm (Intake side (0.039 to 0.055 in.)).
(4) Check that the valve seat contact is in the middle of the valve face with the valve seat width between 1.0 and 1.4 mm (Exhaust side (0.039 to 0.055 in.)).
4. 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 camshaft housing. If the thrust surface is damaged, replace the camshaft.
5. INSPECT CAMSHAFT OIL CLEARANCE
(a) Clean the bearing caps and camshaft journals.
(b) Place the camshafts on the camshaft housing.
(c) Lay a strip of Plastigage across each of the camshaft journals.
(d) Install the bearing caps Installation.
NOTICE:
Do not turn the camshaft.
(e) Remove the bearing caps Removal.
(f) Measure the Plastigage at its widest point.
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.
6. INSPECT COMPRESSION SPRING
(a) Using vernier calipers, measure the free length of the valve spring.
Free length:
53.36 mm (2.1008 in.)
If the free length is not as specified, replace the valve spring.
(b) Using steel squares, measure the deviation of the valve spring.
Maximum deviation:
1.0 mm (0.0394 in.)
If the deviation is greater than the maximum, replace the valve spring.
7. INSPECT INTAKE VALVE
(a) Using a gasket scraper, scrape off any carbon on the valve head.
(b) Using vernier calipers, measure the overall length of the valve.
Standard overall length:
109.34 mm (4.3047 in.)
Minimum overall length:
108.84 mm (4.2850 in.)
If the overall length is less than the minimum, replace the valve.
(c) Using a micrometer, measure the diameter of the valve stem.
Valve stem diameter:
5.470 to 5.485 mm (0.2154 to 0.2159 in.)
If the valve stem diameter is not as specified, check the oil clearance.
(d) Using vernier calipers, measure the valve head margin thickness.
Standard margin thickness:
1.0 mm (0.0571 in.)
Minimum margin thickness:
0.5 mm (0.0197 in.)
If the margin thickness is less than the minimum, replace the valve.
8. INSPECT EXHAUST VALVE
(a) Using a gasket scraper, scrape off any carbon on the valve head.
(b) Using vernier calipers, measure the overall length of the valve.
Standard overall length:
108.25 mm (4.2618 in.)
Minimum overall length:
107.75 mm (4.2421 in.)
If the overall length is less than the minimum, replace the valve.
(c) Using a micrometer, measure the diameter of the valve stem.
Valve stem diameter:
5.465 to 5.480 mm (0.2152 to 0.2157 in.)
If the valve stem diameter is not as specified, check the oil clearance.
(d) Using vernier calipers, measure the valve head margin thickness.
Standard margin thickness:
1.01 mm (0.0398 in.)
Minimum margin thickness:
0.5 mm (0.0197 in.)
If the margin thickness is less than the minimum, replace the valve.
9. INSPECT VALVE GUIDE BUSH OIL CLEARANCE
(a) Using a caliper gauge, measure the inside diameter of the guide bush.
Bushing inside diameter:
5.510 to 5.530 mm (0.2169 to 0.2177 in.)
(b) Subtract the valve stem diameter measurement from the guide bush inside diameter measurement.
Standard oil clearance:
Maximum oil clearance:
If the clearance is greater than the maximum, replace the valve and guide bush.