Disassembly, Inspection and Assembly

Note: For additional information on camshaft removal refer to camshaft, engine, service and repair: Service and Repair

CYLINDER HEAD AND VALVE TRAIN COMPONENTS

- Tools Required
- MKM-571-B Gauge
- KM-340-0 Cutter Set
- KM-340-7 Guide Drift
- KM-340-13 Cutters
- KM-340-26 Cutters
- KM-348 Valve Spring Compressor
- KM-653 Adapter
- KM-805 Valve Guide Reamer

Disassembly Procedure
1. Remove the cylinder head with the intake manifold and the exhaust manifold attached.
2. Remove the coolant temperature sensor (CTS).
3. Remove the exhaust manifold heat shield bolts.
4. Remove the exhaust manifold heat shield.





5. Remove the exhaust manifold retaining nuts in the sequence shown.
6. Remove the exhaust manifold.
7. Remove the exhaust manifold gasket.
8. Remove the exhaust manifold studs.
9. Remove the thermostat housing mounting bolts.
10. Remove the thermostat housing assembly.





11. Remove the fuel rail retaining bolts and the fuel rail assembly.





12. Remove the intake manifold retaining nuts and retaining bolts in the sequence shown.
13. Remove the intake manifold.
14. Remove the intake manifold gasket.
15. Remove the intake manifold studs.





16. Remove the electronic ignition (EI) system ignition coil mounting bolts.
17. Remove the EI system ignition coil with the ignition wires attached.
18. Remove the EI system ignition coil mounting bracket bolts.
19. Remove the EI system ignition coil mounting bracket.
20. Remove the exhaust gas recirculation (EGR) valve adapter bolts.
21. Remove the EGR valve adapter.
22. Remove the EGR valve adapter gasket.
23. Remove the spark plugs.





24. Remove the camshaft cap bolts and in the sequence shown.
25. Remove the intake camshaft caps. Maintain the correct positions for installation.
26. Remove the intake camshaft.





27. Remove the intake valve lash adjusters.
28. Remove the exhaust camshaft caps. Maintain the correct positions for installation.
29. Remove the exhaust camshaft.
30. Remove the exhaust valve lash adjusters.





31. Compress the valve springs with the valve spring compressor KM-348 and the adapter KM-653.
32. Remove the valve retainers.
33. Remove the valve spring compressor KM-348 and the adapter KM-653.
34. Remove the valve spring caps.
35. Remove the valve springs. Maintain the original position of the valves springs for installation.





36. Remove the valves. Maintain the original position of the valves for installation.
37. Remove the valve stem seals.

Cylinder Head Inspection
1. Clean the sealing surfaces.
2. Inspect the cylinder head gasket and mating surfaces for leaks, corrosion and blowby.
3. Inspect the cylinder head for cracks.





4. Inspect the length and width of the cylinder head using a feeler gauge and a straight edge.
5. Check the sealing surfaces for deformation and warpage. The cylinder head sealing surfaces must be flat within 0.050 mm (0.002 inch) maximum.





6. Measure the height of the cylinder head from sealing surface to sealing surface. The cylinder head height should be 138.13 to 138.18 mm (5.438 to 5.440 inches). If the cylinder head height is less than 138.13 mm (5.438 inches), replace the cylinder head.
7. Inspect all threaded holes for damage.
8. Inspect all valve seats for excessive wear and burned spots.

Valve Inspection





1. Inspect the valve stem tip for wear.
2. Inspect the valve retainer grooves and the oil seal grooves for chips and wear.
3. Inspect the valves for burns or cracks.
4. Inspect the valve stem for burrs and scratches.
5. Inspect the valve stem. The valve stem must be straight.
6. Inspect the valve face for grooving. If the groove is so deep that refacing the valve would result in a sharp edge, replace the valve.
7. Inspect the valve spring. If the valve spring ends are not parallel, replace the valve spring.





8. Measure the valve spring height. If the valve spring height does not match the specifications, replace the valve spring.
9. Inspect the valve spring seating surface of the valve rotators for wear or gouges. Replace as required.

Cleaning Procedure





1. Clean the cylinder head.
2. Clean the valve guides.
3. Clean all of the threaded holes.
4. Clean all carbon, oil, and varnish from the valves.

Cylinder Head Overhaul
Valve Grind-in
1. Lubricate the valve stem using a fine-grained paste.





2. Lift the valve rhythmically from the seat with a commercially available valve grinding tool in order to distribute the paste.





3. Check the contact pattern on the valve head and in the cylinder head.
4. Clean the valves, the valve guides, and the cylinder head.

Valve Grind





1. Make sure there are no crater line burns on the valve cone.
2. The valve may be reground only two times. Do not grind the valve stem end.
3. The angle at the valve face is 45 degrees.
4. Inspect the assembly height of the intake valves and the exhaust valves.

Valve Guide - Ream





1. Measure the diameter of the valve guide using gauge MKM-571-B and a commercially available inside micrometer.

Important: Valve oversizes may already have been fitted in production.








2. An oversize service code is on the valve guide and the valve stem end. The above table gives the correct size, reamer, and production code for each service.
3. Ream the valve guide from the upper side of the cylinder head to the next oversize.
4. After reaming, cross out the code and emboss the valve guide with the new code.

Valve Seat - Cut
1. Place the cylinder head on wooden blocks.





2. Cut the intake and the exhaust valve seats using the guide drift KM-340-7 as follows:
- Valve seat: A 45-degree side using the cutter KM-340-13.
- Upper correction angle: A 30-degree side using the cutter KM-340-13.
- Lower Correction Angle: A 60-degree side using cutter KM-340-26.
3. Clean the chippings from the cylinder head.
4. Inspect the dimension to make sure the valve seat width is as follows.
- Intake: 1.17 to 1.57 mm (0.046 to 0.062 inch).
- Exhaust: 1.07 to 1.47 mm (0.042 to 0.058 inch).
5. Inspect the assembly height of the intake valves and the exhaust valves.
6. If the dimension is exceeded, install new valves.
7. Inspect the assembly height of the intake valves and the exhaust valves again.
8. If the valve assembly height is still too large despite replacing the valves, replace the cylinder head.

Assembly Procedure





1. Install the valve stem seals.
2. Lubricate the valve stems with engine oil.
3. Carefully install the valves in their original positions. Do not damage the valve stem seals.
4. Install the valve springs in their original positions.
5. Install the valve spring caps.





6. Compress the valve springs with the valve spring compressor KM-348 and adapter KM-653.
7. Install the valve retainers.
8. Remove the valve spring compressor KM-348 and adapter KM-653.
9. Lubricate the valve lash adjusters with engine oil.





10. Install the valve lash adjusters.
11. Install the intake camshaft.
12. Install the intake camshaft caps in their original positions.
13. Install the exhaust camshaft.
14. Install the exhaust camshaft caps in their original positions.
15. Install the camshaft cap bolts.





16. Tighten the camshaft cap bolts gradually and in the sequence shown for each camshaft cap
- Tighten the camshaft cap bolts to 16 Nm (12 ft. lbs.).
17. Install the spark plugs.
- Tighten the spark plugs to 25 Nm (18 ft. lbs.).
18. Install the exhaust gas recirculation (EGR) valve adapter gasket.
19. Install the EGR valve adapter.
20. Install the EGR valve adapter bolts.
- Tighten the exhaust gas recirculation valve adapter bolts to 25 Nm (18 ft. lbs.).
21. Install the EI system ignition coil mounting bracket.





22. Install the EI system ignition coil mounting bracket bolts.
- Tighten the electronic ignition system ignition coil mounting bracket bolts to 10 Nm (89 inch lbs.).
23. Install the EI ignition coil with the ignition wires attached.
24. Install the EI ignition coil mounting bolts.
- Tighten the electronic ignition system ignition coil mounting bolts to 10 Nm (89 inch lbs.).
25. Install the intake manifold studs.
26. Install the intake manifold gasket.
27. Install the intake manifold.





28. Install the intake manifold retaining nuts and retaining bolts in the sequence shown.
- Tighten the intake manifold retaining nuts/bolts to 25 Nm (18 ft. lbs.).





29. Install the fuel rail assembly with the bolts.
- Tighten the fuel rail retaining bolts to 25 Nm (18 ft. lbs.).
30. Install the thermostat housing assembly.
31. Install the thermostat housing mounting bolts.
- Tighten the thermostat housing mounting bolts to 20 Nm (15 ft. lbs.).
32. Install the exhaust manifold studs.
33. Install the exhaust manifold gasket.
34. Install the exhaust manifold.





35. Install the exhaust manifold retaining nuts in the sequence shown.
- Tighten the exhaust manifold retaining nuts to 25 Nm (18 ft. lbs.).
36. Install the exhaust manifold heat shield.
37. Install the exhaust manifold heat shield bolts.
- Tighten the exhaust manifold heat shield bolts to 15 Nm (11 ft. lbs.).





38. Install the CTS.
- Tighten the coolant temperature sensor to 20 Nm (15 ft. lbs.).
39. Install the cylinder head with the intake manifold and the exhaust manifold attached.