Part 2

OVERHAUL
20. INSPECT CAMSHAFT

a. Inspect the circle runout.
1. Place the camshaft on V-blocks.
2. 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 camshaft.

b. Using a micrometer, measure the cam lobe height.
Standard cam lobe height: 42.610 - 42.710 mm (1.6776 - 1.6815 inch)
Minimum cam lobe height: 42.46 mm (1.6717 inch)
If the cam lobe height is less than minimum, replace the camshaft.
c. Inspect the journal diameter of the camshaft.

1. Using a micrometer, measure the journal diameter of the camshaft for the camshaft bearing.
Journal diameter: 26.954 - 26.970 mm (1.0612 - 1.0618 inch)
If the journal diameter is not as specified, check the oil clearance.

2. Using a micrometer, measure the journal diameter for the camshaft timing tube.
Journal diameter: 30.984 - 31.000 mm (1.2198 - 1.2205 inch)

d. Inspect the journal diameter of the camshaft timing tube.
1. Using a micrometer, measure the journal diameter.
Journal diameter: 39.955 - 39.964 mm (1.5730 - 1.5734 inch)
If the journal diameter is not as specified, check the oil clearance.

e. Install the camshaft timing tube to the camshaft, and check the timing tube turn smoothly.
If necessary, replace the timing tube and camshaft.

f. Check the oil clearance.
1. Install the camshaft timing tube to the camshaft.
2. Clean the bearing caps and journals.
3. Check that bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and cylinder head as a set.
4. Place the camshaft on the cylinder head.
5. Lay a strip of Plastigage across each of the journals.
6. Install the bearing caps.

NOTICE: Do not turn the camshaft.

7. Remove the bearing caps.

8. Measure the Plastigage at its widest point.

Standard oil clearance

Maximum oil clearance

If the oil clearance is greater than maximum, replace the camshaft and timing tube. If necessary, replace the bearing caps and cylinder head as a set.
9. Completely remove the Plastigage.
10. Remove the camshaft.
11. Remove the camshaft timing tube from the camshaft.

g. Check the thrust clearance.
1. Install the camshaft timing tube to the camshaft.
2. Install the camshaft.
3. Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.
Standard thrust clearance: 0.060 - 0.100 mm (0.0024 - 0.0039 inch)
Maximum thrust clearance: 0.13 mm (0.0051 inch)
If the thrust clearance is greater than maximum, replace the camshaft. If necessary, replace the bearing caps and cylinder head as a set.
4. Remove the camshaft.
5. Remove the camshaft timing tube from the camshaft.

h. Check the gear backlash.
1. Install the drive gear to the camshaft timing tube.
2. Install the camshaft timing tube to the camshaft.
3. Install the camshaft and No. 2 camshaft without installing the camshaft sub-gear and front bearing cap.
4. 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 than maximum, replace the drive gear and No. 2 camshaft.
i. Remove the camshaft and No. 2 camshaft.
j. Remove the camshaft timing tube from the camshaft.
k. Remove the drive gear from the camshaft timing tube.
21. INSPECT NO.2 CAMSHAFT

b. Using a micrometer, measure the cam lobe height.
Standard cam lobe height: 42.630 - 42.730 mm (1.6783 - 1.6823 inch)
Minimum cam lobe height: 42.48 mm (1.6724 inch)
If the cam lobe height is less than minimum, replace the No. 2 camshaft.

c. Using a micrometer, measure the journal diameter.
Journal diameter: 26.954 - 26.970 mm (1.0612 - 1.0618 inch)
If the journal diameter is not as specified, check the oil clearance.
d. Check the oil clearance.
1. Clean the bearing caps and journals.

2. Check that bearings for flaking and scoring. If the bearings are damaged, replace the bearing caps and cylinder head as a set.
3. Place the No. 2 camshaft on the cylinder head.
4. Lay a strip of Plastigage across each of the journals.
5. Install the bearing caps.

NOTICE: Do not turn the No. 2 camshaft.

6. Remove the bearing caps.

7. Measure the Plastigage at its widest point.
Standard oil clearance: 0.030 - 0.067 mm (0.0012 - 0.0026 inch)
Maximum oil clearance: 0.100 mm (0.0039 inch)
If the oil clearance is greater than maximum, replace the No. 2 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
8. Completely remove the Plastigage.
9. Remove the No. 2 camshaft.

e. Check the thrust clearance.
1. Install the camshaft.
2. Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.
Standard thrust clearance: 0.030 - 0.075 mm (0.0012 - 0.0030 inch)
Maximum thrust clearance: 0.12 mm (0.0047 inch)
If the thrust clearance is greater than maximum, replace the No. 2 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
3. Remove the No. 2 camshaft.
22. INSPECT NO.3 CAMSHAFT SUB-ASSY

b. Using a micrometer, measure the cam lobe height.
Standard cam lobe height: 42.610 - 42.710 mm (1.6776 - 1.6815 inch)
Minimum cam lobe height: 42.46 mm (1.6717 inch)
If the cam lobe height is less than minimum, replace the No. 3 camshaft.
c. Inspect the journal diameter of the camshaft.

1. Using a micrometer, measure the journal diameter of the No. 3 camshaft for the camshaft bearing.
Journal diameter: 26.954 - 26.970 mm (1.0612 - 1.0618 inch)
If the journal diameter is not as specified, check the oil clearance.

2. Using a micrometer, measure the journal diameter for the camshaft timing tube.
Journal diameter: 30.984 - 31.000 mm (1.2198 - 1.2205 inch)

e. Install the timing tube to the No. 3 camshaft, and check the timing tube turn smoothly.
If necessary, replace the timing tube and No. 3 camshaft.

f. Check the oil clearance.
1. Install the camshaft timing tube to the No. 3 camshaft.
2. Clean the bearing caps and journals.
3. Check that bearings for flaking and scoring.
If the bearings are damaged, replace the bearing caps and cylinder head as a set.
4. Place the No. 3 camshaft on the cylinder head.
5. Lay a strip of Plastigage across each of the journals.
6. Install the bearing caps.

NOTICE: Do not turn the camshaft.

7. Remove the bearing caps.

8. Measure the Plastigage at its widest point.

Standard oil clearance

Maximum oil clearance

If the oil clearance is greater than maximum, replace the No. 3 camshaft and timing tube. If necessary, replace the bearing caps and cylinder head as a set.
9. Completely remove the Plastigage.
10. Remove the camshaft.
11. Remove the camshaft timing tube from the No. 3 camshaft.

g. Check the thrust clearance.
1. Install the camshaft timing tube to the No. 3 camshaft.
2. Install the No. 3 camshaft.
3. Using a dial indicator, measure the thrust clearance while moving the No. 3 camshaft back and forth.
Standard thrust clearance: 0.060 - 0.100 mm (0.0024 - 0.0039 inch)
Maximum thrust clearance: 0.13 mm (0.0051 inch)
If the thrust clearance is greater than maximum, replace the No. 3 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
4. Remove the No. 3 camshaft.
5. Remove the camshaft timing tube from the No. 3 camshaft.

h. Check the gear backlash.
1. Install the drive gear to the camshaft timing tube.
2. Install the camshaft timing tube to the No. 3 camshaft.
3. Install the No. 3 camshaft and No. 4 camshaft without installing the camshaft sub-gear and front bearing cap.
4. 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 than maximum, replace the drive gear and No. 4 camshaft.
i. Remove the No. 3 camshaft and No. 4 camshaft.
j. Remove the camshaft timing tube from the No. 3 camshaft.
k. Remove the drive gear from the camshaft timing tube.
23. INSPECT NO.4 CAMSHAFT SUB-ASSY

2. Check that bearings for flaking and scoring. If the bearings are damaged, replace the bearing caps and cylinder head as a set.
3. Place the No. 4 camshaft on the cylinder head.
4. Lay a strip of Plastigage across each of the journals.
5. Install the bearing caps.

NOTICE: Do not turn the No. 4 camshaft.

6. Remove the bearing caps.

7. Measure the Plastigage at its widest point.
Standard oil clearance: 0.030 - 0.067 mm (0.0012 - 0.0026 inch)
Maximum oil clearance: 0.100 mm (0.0039 inch)
If the oil clearance is greater than maximum, replace the No. 4 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
8. Completely remove the Plastigage.
9. Remove the No. 4 camshaft.

e. Check the thrust clearance.
1. Install the camshaft.
2. Using a dial indicator, measure the thrust clearance while moving the No. 4 camshaft back and forth.
Standard thrust clearance: 0.030 - 0.075 mm (0.0012 - 0.0030 inch)
Maximum thrust clearance: 0.12 mm (0.0047 inch)
If the thrust clearance is greater than maximum, replace the No. 4 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
3. Remove the No. 4 camshaft.

24. INSPECT CYLINDER HEAD SET BOLT
a. Using vernier calipers, measure the thread outside diameter of the bolt.
Standard outside diameter: 9.770 - 9.960 mm (0.3846 - 0.3921 inch)
Minimum outside diameter: 9.70 mm (0.3819 inch)
If the diameter is less than minimum, replace the bolt.
25. INSTALL SPARK PLUG TUBE

HINT: When using a new cylinder head, spark plug tubes must be installed.

a. Apply adhesive to the end of the spark plug tube.
Adhesive: Part No. 08833-00070, THREE BOND 1324 or equivalent

b. Using a wooden block and hammer, tap in a new spark tube until there is 48.4 - 49.6 mm (1.906 - 1.953 inch protruding from the camshaft bearing cap installation surface of the cylinder head.

NOTICE: Avoid tapping a new spark plug tube in too far by measuring the amount of the protrusion while tapping.

26. INSTALL TIGHT PLUG NO.1
a. Apply adhesive to the end of the spark plug tube.
Adhesive: Part No.08833-00070, THREE BOND 1324 or equivalent
b. Using SST and a hammer, tap in a new tight plug as shown in the illustration.
SST 09950-60010 (0951-00200), 09950-70010 (09951-07100)

27. INSTALL RING W/HEAD PIN

28. INSTALL STUD BOLT

29. INSTALL VALVE STEM OIL O SEAL OR RING
a. Using SST, push in a new oil seal.
SST 09201-41020

HINT: The oil seal for intake is brown and the oil seal for exhaust is gray.

30. INSTALL INTAKE VALVE
a. Install the valve, spring seat, compression spring and spring retainer.

b. Using SST, compress the compression spring and place the 2 keepers around the valve stem.
SST 09202-70020 (09202-00010)

c. Using a plastic-faced hammer and the valve stem (not in use) tip wound with vinyl tape, lightly tap the valve stem tip to assure proper fit.

NOTICE: Be careful not do damage the valve stem tip.

31. INSTALL EXHAUST VALVE

a. Install the valve, spring seat, compression spring and spring retainer.
b. Using SST, compress the compression spring and place the 2 keepers around the valve stem.