Inspection

Inspection

Cylinder Head
1. Inspect for flatness.
Using a precision straight edge and feeler gauge, measure the surface contacting cylinder block and the manifolds for warpage.

Flatness of cylinder head gasket surface
Standard : 0.03mm(0.0012in.) or less
Flatness of manifold gasket surface
Standard : 0.15mm(0.0059in.) or less





2. Inspect for cracks.
Check the combustion chamber, intake ports, exhaust ports and cylinder block surface for cracks. If cracked, replace the cylinder head.

Valve And Valve Spring
1. Inspect valve stems and valve guides.
(1) Using a caliper gauge, measure the inside diameter of the valve guide.

Valve guide inside diameter
Intake / Exhaust :
6.000 - 6.015mm (2.2362 - 2.2368in.)





(2) Using a micrometer, measure the outer diameter of the valve stem.

Valve stem outer diameter
Intake : 5.965 - 5.980mm (0.2348 - 0.2354in.)
Exhaust : 5.950 - 5.965mm (0.2343 - 0.2348in.)





(3) Calculate the clearance between the valve guides and the stems by difference between the valve stem measured diameter and the valve guide measured inside diameter.

Valve stem-to-guide clearance
[Standard]
Intake : 0.020 - 0.050mm (0.0008 - 0.0020in.)
Exhaust : 0.035 - 0.065mm (0.0014 - 0.0026in.)
[Limit]
Intake : 0.10mm (0.0039in.) or less
Exhaust : 0.13mm (0.0051in.) or less


2. Inspect valves.
(1) Check the valve face angle.
(2) Check that the surface of the valve for wear.
If the valve face is worn, replace the valve.
(3) Check the valve head margin thickness.
If the margin thickness is less than the specification, replace the valve.

Specification
Intake : 1.0mm(0.0394in.)
Exhaust : 1.3mm(0.0512.)





(4) Check the valve length.

Length
Intake : 110.1mm(4.3346in)
Exhaust : 111.1mm(4.3740in)


(5) Check the surface of the valve stem tip for wear.
If the valve stem tip is worn, replace the valve.
3. Inspect valve seats
(1) Check the valve seat for evidence of overheating or improper contact with the valve face.
If the valve seat is worn, replace cylinder head.
(2) Before reconditioning the seat, check the valve guide for wear. If the valve guide is worn, replace the valve guide first.
(3) Recondition the valve seat with a valve seat grinder or cutter. The valve seat contact width should be within specifications and centered on the valve face.
4. Inspect valve springs.
(1) Using a steel square, measure the out-of-square of the valve spring.
(2) Using vernier calipers, measure the free length of the valve spring.

Valve spring
[Standard]
Free height : 46.8mm (1.8425in.)
Out-of-square : 1.5° or less






MLA(Mechanical Lash Adjuster)
1. Inspect MLA.
Using a micrometer, measure the MLA outside diameter.

MLA O.D.
Intake/Exhaust :
29.964 - 29.980mm(1.1797 - 1.1803in.)


2. Using a caliper gauge, measure MLA tappet bore inner diameter of cylinder head.

Tappet bore I.D.
Intake/Exhaust :
30.000 - 30.025mm(1.1811 - 1.1821in.)


3. Calculate the clearance by subtracting MLA outside diameter measurement from tappet bore inside diameter measurement.

MLA to tappet bore clearance
[Standard]
Intake/Exhaust : 0.020 - 0.061mm(0.0008 - 0.0024in.)
[Limit]
Intake/Exhaust : 0.07mm(0.0027in.) or less


Camshaft
1. Inspect cam lobes.
Using a micrometer, measure the cam lobe height.

Cam height
[Standard value]
Intake : 44.5mm (1.7520in.)
Exhaust : 44.5mm (1.7520in.)





If the cam lobe height is less than standard, replace the camshaft.
2. Check the cam lobe surface for wear or damage. If necessary, replace it.
3. Inspect camshaft journal clearance.
(1) Clean the bearing caps and camshaft journals.
(2) Place the camshafts on the cylinder head.
(3) Lay a strip of plastigage across each of the camshaft journals.




(4) Install the bearing caps with the tightening torque.

CAUTION:
Do not turn the camshaft.

(5) Remove the bearing caps.
(6) Measure the plastigage at its widest point.

Bearing oil clearance
[Standard value]
Intake : 0.020 - 0.057mm (0.0008 - 0.0022in.)
Exhaust : 0.020 - 0.057mm (0.0008 - 0.0022in.)





If the oil clearance is greater than the maximum, replace the camshaft. If necessary, replace the cylinder head.
(7) Completely remove the plastigage.
(8) Remove the camshafts.
4. Inspect camshaft end play.
(1) Install the camshafts.
(2) Using a dial indicator, measure the end play while moving the camshaft back and forth.

Camshaft end play
[Standard value] : 0.1 - 0.2mm(0.0039 - 0.0079in.)





If the end play is greater than the maximum, replace the camshaft. If necessary, replace the cylinder head.
(3) Remove the camshafts.

CVVT Assembly
1. Inspect CVVT assembly.
(1) Fix the CVVT assembly with a vice. Ensure that the cam lobe and journal is not damaged.
(2) Check that the CVVT assembly will not turn.
It should not be turned.
(3) Apply vinyl tape to the retard hole except the one(A) indicated by the arrow in the illustration.




(4) Wind tape around the tip of the air gun and apply air of approx. 150kpa(1.5kgf/cm2, 21psi) to the port of the camshaft.
(Perform this in order to release the lock pin for the maximum delay angle locking.)

NOTE:
When the oil splashes, wipe it off with a shop rag.

(5) After the lock pin released, the CVVT assembly can turned in advanced direction.
If the air applied is leaked much, the lock pin can not be released.
(6) Except the position where the lock pin meets at the maximum delay angle, let the CVVT assembly turn back and forth and check the movable range and that there is no resistance to movement.

Standard : Movable smoothly in the range about 30°


(7) Turn the CVVT assembly with your hand in retard direction and lock it at the maximum delay angle position.