Part 2

CYLINDER HEAD (Continued)

11. INSPECT NO. 2 CAMSHAFT

Exhaust Of RH Bank:

(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 in.)
If the circle runout is greater than the maximum, replace the No. 2 camshaft.

Exhaust Of RH Bank:

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

Exhaust Of RH Bank:

(c) Using a micrometer, measure the journal diameter.
Standard journal diameter: 26.954 to 26.970 mm (1.0612 to 1.0618 in.)
If the journal diameter is not as specified, check the oil clearance.

Exhaust Of RH Bank:

(d) Check the oil clearance.
(1) Clean the bearing caps and journals.
(2) Check the 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: Be careful not to turn the No. 2 camshaft.

(6) Remove the bearing caps.

Exhaust Of RH Bank:

(7) Measure the Plastigage at its widest point.
Standard oil clearance: 0.030 to 0.067 mm (0.0012 to 0.0026 in.)
Maximum oil clearance: 0.100 mm (0.0039 in.)
If the oil clearance is greater than the 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.

Exhaust Of RH Bank:

(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 to 0.075 mm (0.0012 to 0.0030 in.)
Maximum thrust clearance: 0.12 mm (0.0047 in.)
If the thrust clearance is greater than the maximum, replace the No. 2 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
(3) Remove the No. 2 camshaft.

12. INSPECT NO. 3 CAMSHAFT SUB-ASSEMBLY

Intake Of LH Bank:

(b) Using a micrometer, measure the cam lobe height.
Standard cam lobe height: 42.610 to 42.710 mm (1.6776 to 1.6815 in.)
Minimum cam lobe height: 42.46 mm (1.6717 in.)
If the cam lobe height is less than the minimum, replace the No. 3 camshaft.

Intake Of LH Bank:

(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.
Standard journal diameter: 26.954 to 26.970 mm (1.0612 to 1.0618 in.)
If the journal diameter is not as specified, check the oil clearance.

Intake Of LH Bank:

(2) Using a micrometer, measure the journal diameter for the camshaft timing tube.
Standard journal diameter: 30.984 to 31.000 mm (1.2198 to 1.2205 in.)
If the journal diameter is not as specified, check the oil clearance.

Intake Of LH Bank:

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

Intake Of LH Bank:

(e) Install the timing tube to the No. 3 camshaft, and check that the timing tube turns smoothly.
If necessary, replace the timing tube and No. 3 camshaft.

Intake Of LH Bank:

(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 the 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: Be careful not to turn the camshaft.

(7) Remove the bearing caps.

Intake Of LH Bank:

(8) Measure the Plastigage at its widest point.

Standard oil clearance:

Maximum oil clearance:

If the oil clearance is greater than the 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.

Intake Of LH Bank:

(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 to 0.100 mm (0.0024 to 0.0039 in.)
Maximum thrust clearance: 0.13 mm (0.0051 in.)
If the thrust clearance is greater than the 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.

Intake Of LH Bank:

(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 to 0.200 mm (0.0008 to 0.0079 in.)
Maximum backlash: 0.30 mm (0.0188 in.)
If the backlash is greater than the 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.

13. INSPECT NO. 4 CAMSHAFT SUB-ASSEMBLY

Exhaust Of LH Bank:

(c) Using a micrometer, measure the journal diameter.
Standard journal diameter: 26.954 to 26.970 mm (1.0612 to 1.0618 in.)
If the journal diameter is not as specified, check the oil clearance.

Exhaust Of LH Bank:

(d) Check the oil clearance.
(1) Clean the bearing caps and journals.
(2) Check the 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: Be careful not to turn the No. 4 camshaft.

(6) Remove the bearing caps.

Exhaust Of LH Bank:

(7) Measure the Plastigage at its widest point.
Standard oil clearance: 0.030 to 0.067 mm (0.0012 to 0.0026 in.)
Maximum oil clearance: 0.100 mm (0.0039 in.)
If the oil clearance is greater than the 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.

Exhaust Of LH Bank:

(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 oil clearance: 0.030 to 0.075 mm (0.0012 to 0.0030 in.)
Maximum oil clearance: 0.12 mm (0.0047 in.)
If the thrust clearance is greater than the maximum, replace the No. 4 camshaft. If necessary, replace the bearing caps and cylinder head as a set.
(3) Remove the No. 4 camshaft.

14. INSPECT CYLINDER HEAD SET BOLT
(a) Using a vernier caliper, measure the thread outside diameter of the bolt.
Standard outside diameter: 9.770 to 9.960 mm (0.3846 to 0.3921 in.)
Minimum outside diameter: 9.70 mm (0.3819 in.)
If the diameter is less than the minimum, replace the bolt.

REPLACEMENT
1. REMOVE INTAKE VALVE GUIDE BUSH

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

(b) Using SST and a hammer, tap out the guide bush.
SST 09201-01055, 09950-70010 (09951-07100)
2. INSTALL INTAKE VALVE GUIDE BUSH

(a) Using a caliper gauge, measure the bush bore diameter of the cylinder head.

(b) Select a new guide bush (STD or O/S 0.05).

Bush bore diameter:

HINT:
^ If the bush bore diameter of the cylinder head is greater than 10.306 mm (0.4057 in.), machine the bush bore diameter to between 10.335 and 10.356 mm (0.4068 to 0.4077 in.).
^ If the bush bore diameter of the cylinder head is greater than 10.356 mm (0.4077 in.), replace the cylinder head.

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

Intake bush length: 34.5 mm (1.358 in.)

(c) Gradually heat the cylinder head to approximately 80 to 100°C (176 to 212°F).
(d) Using SST and a hammer, tap in a new guide bush to the specified protrusion height.
SST 09201-01055, 09950-70010 (09951-07100)
Protrusion height (H): 9.2 to 9.8 mm (0.362 to 0.386 in.)

(e) Using a sharp 5.5 mm reamer, ream the guide bush to obtain the standard specified clearance between the guide bush and valve stem.

3. REMOVE EXHAUST VALVE GUIDE BUSH

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

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

4. INSTALL EXHAUST VALVE GUIDE BUSH

(a) Using a caliper gauge, measure the bush bore diameter of the cylinder head.
(b) Select a new guide bush (STD or O/S 0.05).

Bush bore diameter:

HINT:
^ If the bush bore diameter of the cylinder head is greater than 10.306 mm (0.4057 in.), machine the bush bore diameter to between 10.335 and 10.356 mm (0.4068 to 0.4077 in.).
^ If the bush bore diameter of the cylinder head is greater than 10.356 mm (0.4077 in.), replace the cylinder head.

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

Exhaust bush length: 40.5 mm (1.594 in.)

(e) Using a sharp 5.5 mm reamer, ream the guide bush to obtain the standard specified clearance between the guide bush and valve stem.