Part 2

DISASSEMBLY





13. INSPECT CAMSHAFT FOR RUNOUT
a. Place the camshaft on V-blocks.
b. Using a dial indicator, measure the circle runout at the center journal.
Maximum circle runout: 0.06 mm (0.0024 inch)
If the circle runout is greater than maximum, replace the cam shaft.





14. INSPECT CAM LOBES
Using a micrometer, measure the cam lobe height.





Standard cam lobe height





Minimum cam lobe height

If the cam lobe height is less than minimum, replace the cam shaft.





15. INSPECT CAMSHAFT JOURNALS
Using a micrometer, measure the journal diameter.





Journal diameter

If the journal diameter is not as specified, check the oil clearance.





16. INSPECT CAMSHAFT BEARINGS
Check that bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and cylinder head as a set.
17. INSPECT CAMSHAFT JOURNAL 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 journal.





d. Install the bearing caps.
Torque: 16 Nm (160 kgf-cm, 12 ft. lbs.)

NOTICE: Do not turn the camshaft.

e. Remove the bearing caps.





f. Measure the Plastigage at its widest point.





Standard oil clearance





Maximum oil clearance

If the oil clearance is greater than maximum, replace the cam shaft. If necessary, replace the bearing caps and cylinder head as a set.
g. Completely remove the Plastigage.
h. Remove the camshafts.





18. INSPECT CAMSHAFT THRUST CLEARANCE
a. Install the camshafts.
b. Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.
Standard thrust clearance: 0.040 - 0.090 mm (0.0016 - 0.0035 inch)
Maximum thrust clearance: 0.12 mm (0.0047 inch)
If the thrust clearance is greater than maximum, replace the camshaft. If necessary, replace the bearing caps and cylinder head as a set.
c. Remove the camshafts.





19. INSPECT CAMSHAFT GEAR BACKLASH
a. Install the camshafts without installing the exhaust cam sub-gear.
b. Using a dial indicator, measure the backlash.
Standard backlash: 0.020 - 0.200 mm (0.0008 - 0.0079 inch)
Maximum backlash: 0.30 mm (0.0188 inch)
If the backlash is greater then maximum, replace the camshafts.
c. Remove the camshafts.





20. 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.
21. INSPECT VALVE LIFTERS AND LIFTER BORES





a. Using a caliper gauge, measure the lifter bore diameter of the cylinder head.
Lifter bore diameter: 31.000 - 31.018 mm (1.2205 - 1.2212 inch)





b. Using a micrometer, measure the lifter diameter.
Lifter diameter: 30.966 - 30.976 mm (1.2191 - 1.2195 inch)
c. Subtract the lifter diameter measurement from the lifter bore diameter measurement.
Standard oil clearance: 0.024 - 0.050 mm (0.0009 - 0.0020 inch)
Maximum oil clearance: 0.07 mm (0.0028 inch)
If the oil clearance is greater than maximum, replace the lifter. If necessary, replace the cylinder head.





22. 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.





23. 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

If warpage is greater than maximum, replace the manifold.





24. 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.





25. 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.

REPLACEMENT
1. REPLACE VALVE GUIDE BUSHINGS





a. Gradually heat the cylinder head to 80 - 100°C (176 - 212°F).





b. Using SST and a hammer, tap out the guide bushing.
SST 09201-01055, 09950-70010 (09951-07100)





c. Using a caliper gauge, measure the bushing bore diameter of the cylinder head.





d. Select a new guide bushing (STD or O/S 0.05).
If the bushing bore diameter of the cylinder head is greater than 10.313 mm (0.4060 inch), machine the bushing bore to the following dimension: 10.345 - 10.363 mm (0.4073 - 0.4080 inch)
If the bushing bore diameter of the cylinder head is greater than 10.363 mm (0.4080 inch), replace the cylinder head.





HINT: Different bushings are used for the intake and exhaust.

e. Gradually heat the cylinder head to 80 - 100°C (176 - 212°F).





f. Using SST and a hammer, tap in a new guide bushing to the specified protrusion height.
SST 09201-01055, 09950-70010 (09951-07100)





Protrusion height





g. Using a sharp 5.5 mm reamer, ream the guide bushing to obtain the standard specified clearance between the guide bushing and valve stem.
2. 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.





c. Using needle-nose pliers, pry out the gasket.





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