Inspection [08/2015 - 10/2016]: Procedure

WARNING: This page is about a different car, the 2018 Toyota Sequoia, 2017 Toyota Sequoia, and 2016 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.

INSPECT CAMSHAFT OIL CLEARANCE

Clean the bearing caps, camshaft housing and camshaft journals.
Place the camshafts on the camshaft housing.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Lay a strip of Plastigage across each of the camshaft journals.

Install the camshaft bearing caps. Refer to INSTALLATION [08/2015 - 10/2016] .
NOTE:
Do not turn the camshaft.
Install the camshaft housing. Refer to INSTALLATION [08/2015 - 10/2016] .
NOTE:
Do not turn the camshaft.
Remove the camshaft bearing caps. Refer to REMOVAL [08/2015 - 08/2018] .

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Measure the Plastigage at its widest point.

Standard Oil Clearance

Item	Specified Condition
No. 1 journal	0.030 to 0.065 mm (0.00118 to 0.00256 in.)
Other journal	0.025 to 0.062 mm (0.000984 to 0.00244 in.)

Maximum Oil Clearance

Item	Specified Condition
No. 1 journal	0.10 mm (0.00394 in.)
Other journal	0.09 mm (0.00354 in.)

If the oil clearance is more than the maximum, replace the camshaft. If necessary, replace the camshaft housing.

INSPECT CAMSHAFT THRUST CLEARANCE

Install the camshafts.

Using a dial indicator, measure the thrust clearance while moving the camshaft back and forth.

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Standard thrust clearance

0.08 to 0.135 mm (0.00315 to 0.00531 in.)

Maximum thrust clearance

0.15 mm (0.00591 in.)

If the thrust clearance is more than the maximum, replace the camshaft housing. If the thrust surface is damaged, replace the camshaft.

INSPECT COMPRESSION SPRING

HINT:

The shape of the inner compression spring determines whether the valve spring type described here is A or B.

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

Standard free length

Type	Specified Condition
Valve Spring Type A	49.69 to 53.19 mm (1.96 to 2.09 in.)
Valve Spring Type B	49.38 to 53.38 mm (1.94 to 2.10 in.)

If the free length is not as specified, replace the spring.

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Valve Spring Type A:

Using a steel square, measure the deviation of the inner compression spring.
Maximum deviation

1.0 mm (0.0394 in.)

Maximum angle. Reference)

2°

If the deviation is greater than the maximum, replace the spring.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Valve Spring Type B:

Using a steel square, measure the deviation of the inner compression spring.
Maximum deviation

1.0 mm (0.0394 in.)

Maximum angle. Reference)

2°

If the deviation is greater than the maximum, replace the spring.

INSPECT INTAKE VALVE

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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.)

If the diameter is not as specified, replace the valve and guide bush.

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

Standard margin thickness

1.10 to 1.40 mm (0.0433 to 0.0551 in.)

Minimum margin thickness

0.50 mm (0.0197 in.)

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

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Using a vernier caliper, measure the valve's overall length.

Standard overall length

105.85 mm (4.17 in.)

Minimum overall length

105.35 mm (4.15 in.)

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

INSPECT EXHAUST VALVE

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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.)

If the diameter is not as specified, replace the valve and guide bush.

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

Standard margin thickness

1.25 to 1.55 mm (0.0492 to 0.0610 in.)

Minimum margin thickness

0.50 mm (0.0197 in.)

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

Using a vernier caliper, measure the valve's overall length.

Standard overall length

110.40 mm (4.35 in.)

Minimum overall length

109.90 mm (4.33 in.)

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

INSPECT VALVE GUIDE BUSH OIL CLEARANCE

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

5.51 to 5.53 mm (0.217 to 0.218 in.)

Subtract the valve stem diameter measurement from the guide bush inside diameter measurement.

Standard Oil Clearance

Item	Specified Condition
Intake	0.025 to 0.060 mm (0.00098 to 0.00236 in.)
Exhaust	0.030 to 0.065 mm (0.00118 to 0.00256 in.)

Maximum Oil Clearance

Item	Specified Condition
Intake	0.08 mm (0.00315 in.)
Exhaust	0.10 mm (0.00394 in.)

If the oil clearance is more than the maximum, replace the valve and guide bush.

INSPECT INTAKE VALVE SEAT

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1. Apply a light coat of Prussian blue to the valve face.
2. Lightly press the valve face against the valve seat.
  HINT:
  
  Do not rotate the valve while pressing the valve.
3. Check the valve face and valve seat.
  1. Check that the contact surfaces of the valve seat and valve face are in the middle area of their respective surfaces, with the width between 1.1 to 1.5 mm (0.0433 to 0.0591 in.).
    If not, correct the valve seat.
  2. Check that the contact surfaces of the valve seat and valve face are even around the entire valve seat.
    If not, correct the valve seat.
INSPECT EXHAUST VALVE SEAT

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. Apply a light coat of Prussian blue to the valve face.
2. Lightly press the valve face against the valve seat.
  HINT:
  
  Do not rotate the valve while pressing the valve.
3. Check the valve face and valve seat.
  1. Check that the contact surfaces of the valve seat and valve face are in the middle area of their respective surfaces, with the width between 1.1 to 1.5 mm (0.0433 to 0.0591 in.).
    If not, correct the valve seat.
  2. Check that the contact surfaces of the valve seat and valve face are even around the entire valve seat.
    If not, correct the valve seat.

INSPECT CYLINDER HEAD SUB-ASSEMBLY

Using a precision straightedge and feeler gauge, measure the warpage of the surfaces where the cylinder head contacts the cylinder block and manifold.

Standard Warpage

Item	Specified Condition
Cylinder block side	0.05 mm (0.00197 in.)
Intake manifold side	0.08 mm (0.00315 in.)
Exhaust manifold side	0.05 mm (0.00197 in.)

Maximum warpage

0.10 mm (0.00394 in.)

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

Using a dye penetrant, check the intake ports, exhaust ports and cylinder surface for cracks.

If cracked, replace the cylinder head.