NR Series ENGINE MECHANICAL  CYLINDER HEAD  INSPECTION  

2.188,2.073 2.604,1.656 true 0.531,2.021 1.188,2.594 true 0.583,3.406 1.302,3.792 true 0.354,1.854 0.667,2.01 0.313,0.156 10 false *a 2.625,1.521 2.938,1.677 0.313,0.156 10 false *c 0.385,3.281 0.698,3.438 0.313,0.156 10 false *b

*a	Bottom Side
*b	Intake Manifold Side
*c	Turbocharger Sub-assembly Side

Using a precision straightedge and feeler gauge, check the surfaces which contact the cylinder block sub-assembly, turbocharger sub-assembly and intake manifold for warpage.

Maximum Warpage:

Item	Specified Condition
Bottom side	0.05 mm (0.00197 in.)
Intake manifold side	0.10 mm (0.00394 in.)
Turbocharger sub-assembly side	0.05 mm (0.00197 in.)

HINT:

If the warpage is more than the maximum, replace the cylinder head sub-assembly.

Using a dye penetrant, check the intake ports, exhaust ports and bottom surface of the cylinder head sub-assembly for cracks.

HINT:

If cracks are found, replace the cylinder head sub-assembly.

2.115,0.979 2.427,1.135 0.313,0.156 10 false *a

*a	Overall Length

Using a vernier caliper, measure the overall length of the intake valve.

Standard Overall Length:

103.35 mm (4.07 in.)

Minimum Overall Length:

103.10 mm (4.06 in.)

HINT:

If the overall length is less than the minimum, replace the intake valve.

Using a micrometer, measure the diameter of the valve stem.

Standard Valve Stem Diameter:

5.470 to 5.485 mm (0.215 to 0.216 in.)

HINT:

If the valve stem diameter is not as specified, check the intake valve guide bush oil clearance.

Click hereEngine / Hybrid System>NR Series (ENGINE MECHANICAL)>CYLINDER HEAD>INSPECTION201906,999999,_51,_080739,_0391937,RM100000001HN2O_01_0038,

0.625,1.802 0.938,1.958 0.313,0.156 10 false *a

*a	Margin Thickness

Using a vernier caliper, measure the valve head margin thickness.

Standard Margin Thickness:

1.0 mm (0.0394 in.)

Minimum Margin Thickness:

0.5 mm (0.0197 in.)

HINT:

If the margin thickness is less than the minimum, replace the intake valve.

2.146,1.01 2.458,1.167 0.313,0.156 10 false *a

*a	Overall Length

Using a vernier caliper, measure the overall length of the exhaust valve.

Standard Overall Length:

104.50 mm (4.11 in.)

Minimum Overall Length:

104.25 mm (4.10 in.)

HINT:

If the overall length is less than the minimum, replace the exhaust valve.

Using a micrometer, measure the diameter of the valve stem.

Standard Valve Stem Diameter:

5.465 to 5.480 mm (0.215 to 0.216 in.)

HINT:

If the valve stem diameter is not as specified, check the exhaust valve guide bush oil clearance.

Click hereEngine / Hybrid System>NR Series (ENGINE MECHANICAL)>CYLINDER HEAD>INSPECTION201906,999999,_51,_080739,_0391937,RM100000001HN2O_01_0038,

0.635,1.813 0.948,1.969 0.313,0.156 10 false *a

*a	Margin Thickness

Using a vernier caliper, measure the valve head margin thickness.

Standard Margin Thickness:

1.2 mm (0.0472 in.)

Minimum Margin Thickness:

0.7 mm (0.0276 in.)

HINT:

If the margin thickness is less than the minimum, replace the exhaust valve.

Intake Side:

i.

Using a vernier caliper, measure the free length of the intake valve compression spring.

Standard Free Length:

55.60 mm (2.19 in.)

ii.

1.115,0.667 1.542,0.667 false 0.917,0.594 1.229,0.75 0.313,0.156 10 false *a 0.927,1.292 1.323,1.521 0.396,0.229 10 false *b

*a	Steel Square
*b	40.29 mm (1.59 in.)

Using a steel square, measure the deviation of the intake valve compression spring.

Maximum Angle (Reference):

2°

HINT:

If the angle is more than the maximum, replace the intake valve compression spring.

Exhaust Side:

i.

Using a vernier caliper, measure the free length of the exhaust valve compression spring.

Standard Free Length:

59.30 mm (2.33 in.)

ii.

1.115,0.667 1.542,0.667 false 0.917,0.594 1.229,0.75 0.313,0.156 10 false *a 0.927,1.292 1.323,1.521 0.396,0.229 10 false *b

*a	Steel Square
*b	44.4 mm (1.75 in.)

Using a steel square, measure the deviation of the exhaust valve compression spring.

Maximum Angle (Reference):

2°

HINT:

If the angle is more than the maximum, replace the exhaust valve compression spring.

Using a caliper gauge, measure the inside diameter of the valve guide bush.

Standard Valve Guide Bush Inside Diameter:

5.510 to 5.530 mm (0.217 to 0.218 in.)

2.885,1.177 3.198,1.333 0.313,0.156 10 false *a

*a

Width

Lightly press the valve face against the valve seat.

NOTICE:

Do not rotate the valve while pressing it.