Disassembly

DISASSEMBLY
1. REMOVE WATER OUTLET WITH WATER BYPASS HOSE
Remove the 2 nuts, bolt, water outlet and gasket.
2. REMOVE ENGINE HANGER
3. REMOVE CAMSHAFT POSITION SENSOR
4. REMOVE ECT SENSOR





5. REMOVE VALVE LIFTERS AND SHIMS

HINT: Store the valve lifters and shims in correct order.

6. REMOVE VALVES





a. Using SST compress the valve spring and remove the 2 keepers.
SST 09202-70020 (09202-00010)
b. Remove the spring retainer, valve spring, valve and spring seat.

HINT: Store the valves, valve springs, spring seats and spring retainers in correct order.

c. Using needle-nose pliers, remove the oil seal.

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 top surface of the cylinder block.
c. Using compressed air, blow carbon and oil from the bolt holes.

CAUTION: Protect your eyes when using high-pressure compressed air.

2. INSPECT CYLINDER BLOCK FOR FLATNESS
3. CLEAN CYLINDER HEAD





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

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





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

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





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





d. Clean the cylinder head. Using a soft brush and solvent, thoroughly clean the cylinder head.
4. INSPECT CYLINDER HEAD





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





b. Inspect for the 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.





5. CLEAN VALVES
a. Using a gasket scraper, chip off any carbon from the valve head.
b. Using a wire brush, thoroughly clean the valve.
6. INSPECT VALVE STEMS AND GUIDE BUSHINGS





a. Using a caliper gauge, measure the inside diameter of the guide bushing.
Bushing inside diameter: 6.010 - 6.030 mm (0.2366 - 0.2374 inch)





b. Using a micrometer, measure the diameter of the valve stem.





Valve stem diameter

c. Subtract the valve stem diameter measurement from the guide bushing inside diameter measurement.





Standard oil clearance





Maximum oil clearance

If the clearance is greater than maximum, replace the valve and guide bushing.
7. INSPECT AND GRIND VALVES
a. Grind the valve enough to remove pits and carbon.





b. Check that the valve is ground to the correct valve face angle.
Valve face angle: 44.5°





c. Check the valve head margin thickness.
Standard margin thickness: 0.8 - 1.2 mm (0.031 - 0.047 inch)
Minimum margin thickness: 0.5 mm (0.020 inch)
If the margin thickness is less than minimum, replace the valve





d. Check the valve overall length.





Standard overall length





Minimum overall length

If the overall length is less than minimum, replace the valve.





e. Check the surface of the valve stem tip for wear.
If the valve stem tip is worn, resurface the tip with a grinder or replace the valve.

NOTICE: Do not grind off more than the minimum overall length.

8. INSPECT AND CLEAN VALVE SEATS





a. Using a45° carbide cutter, resurface the valve seats.
Remove only enough metal to clean the seats.





b. Check the valve seating position.
Apply a thin coat of Prussian blue (or white lead) to the valve face. Lightly press the valve against the seat. Do not rotate the valve.
c. Check the valve face and seat for the following:
- If blue appears360° around the face, the valve is concentric. If not, replace the valve.
- If blue appears360° around the valve seat, the guide and face are concentric. If not, resurface the seat.
- Check that the seat contact is in the middle of the valve face with the following width:





If not, correct the valve seats as follows:





1) If the seating is too high on the valve face, use 15° and 45° cutters to correct the seat.





2) If the seating is too low on the valve face, use 75° and 45° cutters to correct the seat.





d. Hand-lap the valve and valve seat with an abrasive compound.
e. After hand-lapping, clean the valve and valve seat.
9. INSPECT VALVE SPRINGS





a. Using a steel square, measure the deviation of the valve spring.
Maximum deviation: 2.0 mm (0.079 inch)
If deviation is greater than maximum, replace the valve spring.
b. Using vernier calipers, measure the free length of the valve spring.





Free length





If the free length is not as specified, replace the valve spring.





c. Using a spring tester, measure the tension of the valve spring at the specified installed length.
Installed tension: 186.2 - 205.8 N (19.0 - 21.0 kgf, 41.9 - 46.3 lbs.) at 34.5 mm (1.358 inch)
If the installed tension is not as specified, replace the valve spring.





10. INSPECT CAMSHAFTS 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: 0.08 mm (0.0031 inch)
If the circle runout is greater than maximum, replace the cam shaft.





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





Standard cam lobe height





Minimum cam lobe height

If the lobe height is less than minimum, replace the camshaft.





12. INSPECT CAMSHAFT JOURNALS
Using a micrometer, measure the journal diameter.
Journal diameter: 28.949 - 28.965 mm (1.1397 - 1.1404 inch)
If the journal diameter is not as specified check the oil clearance.
13. INSPECT CAMSHAFT BEARING
Check the bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and cylinder head as a set.
14. 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 journals.
d. Install the bearing caps.

NOTICE: Do not turn the camshaft.

e. Remove the bearing caps.





f. Measure the Plastigage at its widest point.
Standard oil clearance: 0.035 - 0.072 mm (0.0014 - 0.0028 inch)
Maximum oil clearance: 0.10 mm (0.0039 inch)
If the oil clearance is greater than maximum, replace the cam shaft. If necessary, replace the bearing caps and cylinder head as a set.
Completely remove the Plastigage.





15. 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: 0.080 - 0.190 mm (0.0031 - 0.0075 inch)
Maximum thrust clearance: 0.30 mm (0.0118 inch)
If the thrust clearance is greater than maximum, replace the camshaft. If necessary, replace the bearing caps and cylinder head as a set.





16. 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 - 31.016 mm (1.2205 - 1.2211 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.





17. INSPECT AIR INTAKE CHAMBER
Using a precision straight edge and feeler gauge, measure the surfaces contacting the intake manifold for warpage.
Maximum warpage: 0.15 mm (0.0059 inch)
If warpage is greater than maximum, replace the chamber.





18. INSPECT INTAKE MANIFOLD
Using a precision straight edge and feeler gauge, measure the surfaces contacting the cylinder head and air intake chamber for warpage.
Maximum warpage: 0.15 mm (0.0059 inch)
If warpage is greater than maximum, replace the manifold.





19. INSPECT EXHAUST MANIFOLD
Using a precision straight edge and feeler gauge, measure the surfaces 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 CYLINDER HEAD BOLTS
Using a vernier caliper, measure the thread outside diameter of the bolt.
Standard outside diameter: 10.8 - 11.0 mm (0.425 - 0.433 inch)
Minimum outside diameter: 10.7 mm (0.421 inch)
If the diameter is less than minimum, replace the bolt.

REPLACEMENT
REPLACE VALVE GUIDE BUSHINGS





a. Using SST and a hammer, tap out the guide bushing.
SST 09201-10000 (09201-01060), 09950-70010 (09951-07100)





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





c. Select a new guide bushing (STD or O/S 0.05).
If the bushing bore diameter of the cylinder head is greater than 11.006 mm (0.4333 inch), machine the bushing bore to the following dimension: 11.035 - 11.056 mm (0.4344 - 0.4353 inch)
If the bushing bore diameter of the cylinder head is greater than 11.056 mm (0.4353 inch), replace the cylinder head.





d. Using SST and a hammer, tap in a new guide bushing to the specified protrusion height.
SST 09201-10000 (09201-01060), 09950-70010 (09951-07100)





Protrusion height





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





e. Using a sharp 6 mm reamer, ream the guide bushing to obtain the standard specified clearance between the guide bushing and valve stem.