Camshaft: Testing and Inspection

CAMSHAFT INSPECTION

1. 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 camshaft.

2. Inspect cam lobes.
Using a micrometer, measure the cam lobe height.
Standard cam lobe height:
Intake: 42.11 - 42.21 mm (1.6579 - 1.6618 inch)
Exhaust: 41.96 - 42.06 mm (1.6520 - 1.6559 inch)
Minimum cam lobe height:
Intake: 41.96 mm (1.6520 inch)
Exhaust: 41.81 mm (1.6461 inch)
If the cam lobe height is less than minimum, replace the camshaft.

3. Inspect camshaft journals.
Using a micrometer, measure the journal diameter.
Journal diameter:
Intake: 26.949 - 26.965 mm (1.0610 - 1.0616 inch)
Exhaust: 26.959 - 26.975 mm (1.0613 - 1.0620 inch)
If the journal diameter is not as specified, check the oil clearance.

4. 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.
5. Inspect camshaft journal oil clearance.
(a) Clean the bearing caps and camshaft journals.
(b) Place the camshafts on the cylinder head.

(d) Install the bearing caps.

Torque: 16 Nm (12 ft.lb)

CAUTION: Do not turn the camshaft.

(e) Remove the bearing caps.

(f) Measure the Plastigage at its widest point.
Standard oil clearance:
Intake: 0.035 - 0.072 mm (0.0014 - 0.0028 inch)
Exhaust: 0.025 - 0.062 mm (0.0010 - 0.0024 inch)
Maximum oil clearance:
Intake: 0.10 mm (0.0039 inch)
Exhaust: 0.09 mm (0.0035 inch)
If the oil clearance is greater than maximum, replace the camshaft. If necessary, replace the bearing caps and cylinder head as a set.
(g) Completely remove the Plastigage.
(h) Remove the camshafts.
6. 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.
7. 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.