Cylinder and Camshaft Inspection DOHC

Tools Required

SA9179NE Dial Indicator

Inspection Procedure

1. Install the camshaft and bearing caps. Refer to Cylinder Head Assemble for additional detail.
1. Oil the camshaft journals and install the camshaft. Install the bearing caps with the arrows on the caps pointed toward the camshaft sprockets, front of the cylinder head.

Important

Bolt threads should be lightly oiled prior to installation. The holes must be clean and free from oil and debris.

2. The bolts must be pulled down uniformly.
Tighten

Tighten camshaft bearing cap-to-head (LL0) to 14 N·m (10 lb in).

3. The camshaft should rotate freely. If the camshaft binds, check for burrs in the cylinder head and caps journals.




2. Measure the camshaft thrust, or end play. Using a SA9179NE or equivalent, measure the thrust clearance while moving each camshaft back and forth. If clearance is greater than maximum, replace the cylinder head or camshaft.
Specifications
Thrust Clearance
• Standard: 0.005-0.2 mm (0.002-0.008 in)
• Service Limit: 0.25 mm (0.01 in) max.
3. Remove the camshafts from the cylinder head:
1. Remove the bearing caps.
2. Remove each camshaft.




4. Inspect the camshaft bore for flatness. Using a precision straight edge and feeler gage, measure the surfaces contacting the camshaft for warpage. If warpage is greater than the maximum, replace the cylinder head.
Specifications
Maximum Warpage
• Standard: 0.05 mm (0.002 in) max.
• Service Limit: 0.075 mm (0.003 in) max.




5. Inspect the camshaft:
6. Place the camshaft ends in V-blocks and, using a SA9179NE , or equivalent, measure the total runout at the center journal. If the runout is greater than maximum, replace the camshaft.
Specifications
Circle Total Runout
• Standard: 0.05 mm (0.002 in) max.
• Service Limit: 0.1 mm (0.004 in) max.




7. Using a dial indicator, measure the cam lobe lift/rise. Place the camshaft in V-blocks located next to the lobe being measured.




8. If the cam lobe lift/rise is less than minimum, replace the camshaft.
Specifications
Cam Lobe Lift Rise
• Intake Standard: 8.96-9.04 mm (0.3528-0.3559 in) max.
• Intake Service Limit: 8.91 mm (0.351 in) max.
• Exhaust Standard: 8.66-8.74 mm (0.3409-0.3441 in) max.
• Exhaust Service Limit: 8.61 mm (0.339 in) max.




9. Using a micrometer, measure the journal diameter.
Specifications
Journal Diameter
• Standard: 28.95-28.97 mm (1.1398-1.1406 in)
• Service Limit: 28.925 mm (1.139 in) min.




10. Install the camshaft bearing caps. Using an inside micrometer, measure the housing bore diameter.
Specifications
Bore Diameter
• Standard: 29-29.026 mm (1.141-1.142 in)
• Service Limit: 29.05 mm (1.144 in) max.

Important

Plastigage®, or equivalent can be used to measure the bearing clearance.

11. Subtract the journal diameter measurement from the housing bore diameter measurement. If the clearance is greater than the maximum, replace the camshaft and/or cylinder head.
Specifications
Oil Clearance
• Standard: 0.03-0.076 mm (0.0012-0.003 in)
• Service Limit: 0.125 mm (0.005 in) max.