Part 2

3UZ-FE ENGINE MECHANICAL: CYLINDER HEAD: INSPECTION

10. 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 in.)

* If the circle runout is greater than the maximum, replace the camshaft.

(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 camshaft.

(c) Inspect the journal diameter of the camshaft.

(1) Using a micrometer, measure the journal diameter of the 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.

(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.

(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.

(e) Install the camshaft timing tube to the camshaft, and check that the timing tube turns 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 the 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 the 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 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 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 to 0.200 mm (0.0008 to 0.0079 in.)

Maximum backlash:

0.30 mm (0.0118 in.)

* If the backlash is greater than the 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.

11. INSPECT NO. 2 CAMSHAFT

(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.

(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.

(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.

(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.

(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

(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.

(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.

(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.

(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.

(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.

(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

(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.

(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.

(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.