Cylinder Head Assembly: Testing and Inspection

INSPECTION
1. Clean top surfaces of pistons and cylinder block.

(a) Turn the crankshaft, and bring each piston to Top Dead Center (TDC). Using a gasket scraper, remove all the carbon from the piston top surface.

(b) Using a gasket scraper, remove all the gasket material from the cylinder block surface.
(c) Using compressed air, blow carbon and oil from the bolt holes.

WARNING: Protect your eyes when using high pressure compressed air.

2. Remove gasket material.
Using a gasket scraper, remove all the gasket material from the cylinder block contact surface.

CAUTION: Be careful not to scratch the cylinder block contact surface.

3. Clean combustion chambers.
Using a wire brush, remove all the carbon from the combustion chambers.

CAUTION: Be careful not to scratch the cylinder block contact surface.

4. Clean cylinder heads.
Using a soft brush and solvent, thoroughly clean the cylinder head.

5. Clean valve guide bushings.
Using a valve guide bushing brush and solvent, clean all the guide bushings.

6. Inspect for flatness.
Using a precision straight edge and feeler gauge, measure the surfaces contacting the cylinder block and the manifolds for warpage.
Maximum warpage: 0.10 mm (0.0039 inch)
If warpage is greater than maximum, replace the cylinder head.

7. Inspect for cracks.
Using a dye penetrant, check the combustion chamber, intake ports, exhaust ports and cylinder block surface for cracks. If cracked, replace the cylinder head.

8. Clean valves.
(a) Using a gasket scraper, chip off any carbon from the valve head.
(b) Using a wire brush, thoroughly clean the valve.
9. Inspect valve stems and guide bushings.

(a) Using a caliper gauge, measure the inside diameter of the guide bushing.
Bushing inside diameter: 5.510 - 5.530 mm (0.2169 - 0.2177 inch)

(b) Using a micrometer, measure the diameter of the valve stem.
Valve stem diameter:
Intake: 5.470 - 5.485 mm (0.2154 - 0.2159 inch)
Exhaust: 5.465 - 5.480 mm (0.2152 - 0.2157 inch)
(c) Subtract the valve stem diameter measurement from the guide bushing guide bushing inside diameter measurement.
Standard oil clearance:
Intake: 0.025 - 0.060 mm (0.0010 - 0.0024 inch)
Exhaust: 0.030 - 0.065 mm (0.0012 - 0.0026 inch)
Maximum oil clearance:
Intake: 0.08 mm (0.0031 inch)
Exhaust: 0.10 mm (0.0039 inch)
If the clearance is greater than maximum, replace the valve and guide bushing.
10. If necessary, replace valve guide seals.
11. Inspect and grind valves.

12. Inspect and clean valve seats.
13. Inspect valve springs.
14. Inspect camshafts.

15. Inspect camshaft gear spring.
Using vernier calipers, measure the free distance between the spring ends.
Free distance: 18.2 - 18.8 mm (0.712 - 0.740 inch)
If the free distance is not as specified, replace the gear spring.
16. Inspect valve lifters and lifter bores.

17. Inspect air intake chamber.
Using a precision straight edge and feeler gauge, measure the surface contacting the intake manifold for warpage.
Maximum warpage: 0.10 mm (0.0039 inch)
If warpage is greater than maximum, replace the chamber.

18. Inspect intake manifold.
Using a precision straight edge and feeler gauge, measure the surface contacting the cylinder head and air intake chamber for warpage.
Maximum warpage:
Air intake chamber side: 0.15 mm (0.0059 inch)
Cylinder head side: 0.08 mm (0.0031 inch)
If warpage is greater than maximum, replace the manifold.

19. Inspect exhaust manifolds.
Using a precision straight edge and feeler gauge, measure the surface contacting the cylinder head for warpage.
Maximum warpage: 0.50 mm (0.0196 inch)
If warpage is greater than maximum, replace the manifold.

20. Inspect 12 pointed head cylinder head bolts.
Using vernier calipers, measure the tension portion diameter of the bolt.
Standard outside diameter: 8.95 - 9.05 mm (0.3524 - 0.3563 inch)
Minimum outside diameter: 8.75 mm (0.3445 inch)
If the diameter is less than minimum, replace the bolt.
21. If necessary, replace spark plug tube gaskets.

(a) Bend up the tab on the ventilation baffle plate which prevents the gasket from the slipping out.
(b) Using a screwdriver and hammer, tap out the gasket.

(d) Using SST Replacer # 09608-03071 or equivalent and a hammer, tap in a new gasket until its surface is flush with the upper edge of the cylinder head cover.
(e) Apply a light coat of Multipurpose (MP) grease to the gasket lip.
(f) Return the ventilation plate tab to its original position.