Inspection [10/2015 - ]: Procedure

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INSPECT NO. 1 VALVE ROCKER ARM SUB-ASSEMBLY
1. Turn the roller by hand and check that it turns smoothly.
  If the roller does not turn smoothly, replace the No. 1 valve rocker arm sub-assembly.

INSPECT VALVE LASH ADJUSTER ASSEMBLY

NOTE:

Keep the adjuster free from dirt and foreign matter.
Only use clean engine oil.

Place the valve lash adjuster assembly into a container filled with engine oil.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Correct	*b	Incorrect
*c	Tapered Path	*d	Low Pressure Chamber
*e	High Pressure Chamber	*f	Plunger
*g	Check Ball	-	-

Insert the tip of SST into the plunger and use the tip to press down on the check ball inside the plunger.
- SST: 09276-75010
Squeeze SST and the valve lash adjuster assembly together to move the plunger up and down 5 to 6 times.
Check the movement of the plunger and bleed air.
OK

Plunger moves up and down.

NOTE:
When bleeding air from the high pressure chamber, make sure that the tip of SST is actually pressing the check ball as shown in the illustration. If the check ball is not pressed, air will not bleed.
After bleeding the air, remove SST. Then try to quickly and firmly press the plunger with your fingers.
OK

Plunger is very difficult to move.

If the plunger is easy to move, replace the valve lash adjuster assembly.

INSPECT CAMSHAFT

Inspect the camshaft runout.
1. Place the camshaft on V-blocks.
2. Using a dial indicator, measure the runout at the center journal.
  Maximum Runout
  
  0.03 mm (0.00118 in.)
  
  If the runout is more than the maximum, replace the camshaft.
  
  HINT:
  
  Check the oil clearance after replacing the camshaft.
Inspect the cam lobes.
1. Using a micrometer, measure the cam lobe height.
  Standard Cam Lobe Height
  
  44.155 to 44.255 mm (1.738 to 1.742 in.)
  
  Minimum Cam Lobe Height
  
  44.045 mm (1.734 in.)
  
  If the cam lobe height is less than the minimum, replace the camshaft.

Inspect the camshaft journals.

Using a micrometer, measure the journal diameter.

Standard Journal Diameter

Item	Specified Condition
No. 1 journal	34.449 to 34.465 mm (1.356 to 1.357 in.)
Other journals	22.959 to 22.975 mm (0.904 to 0.905 in.)

If the result is not as specified, check the oil clearance.

INSPECT NO. 2 CAMSHAFT

Inspect the No. 2 camshaft runout.
1. Place the No. 2 camshaft on V-blocks.
2. Using a dial indicator, measure the runout at the center journal.
  Maximum Runout
  
  0.03 mm (0.00118 in.)
  
  If the runout is more than the maximum, replace the No. 2 camshaft.
  
  HINT:
  
  Check the oil clearance after replacing the No. 2 camshaft.
Inspect the cam lobes.
1. Using a micrometer, measure the cam lobe height.
  Standard Cam Lobe Height
  
  43.499 to 43.599 mm (1.713 to 1.716 in.)
  
  Minimum Cam Lobe Height
  
  43.389 mm (1.708 in.)
  
  If the cam lobe height is less than the minimum, replace the No. 2 camshaft.

Inspect the No. 2 camshaft journals.

Using a micrometer, measure the journal diameter.

Standard Journal Diameter

Item	Specified Condition
No. 1 journal	34.449 to 34.465 mm (1.356 to 1.357 in.)
Other journals	22.959 to 22.975 mm (0.904 to 0.905 in.)

If the result is not as specified, check the oil clearance.

INSPECT CAMSHAFT OIL CLEARANCE

NOTE:

Do not turn the camshafts.

Clean the camshaft bearing caps, camshaft housing sub-assembly and camshaft journals.
Place the camshaft and No. 2 camshaft on the camshaft housing sub-assembly.

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Plastigage

Place the No. 1 camshaft bearing cap, No. 2 camshaft bearing cap, No. 3 camshaft bearing cap and No. 4 camshaft bearing cap to the camshaft housing sub-assembly.
Install the 11 bearing cap bolts in the order shown in the illustration.
Torque: 16 N*m (163 kgf*cm, 12 ft.*lbf)

Fig 1: Bearing Cap Bolts Tightening Sequence
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NOTE:
Do not turn the camshafts.
Install the camshaft housing sub-assembly, and then install the 22 bearing cap bolts in the order shown in the illustration.
Torque: 27 N*m (275 kgf*cm, 20 ft.*lbf)

Fig 2: Bearing Cap Bolts Tightening Sequence
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Remove the 4 camshaft bearing caps.
See step 32

Measure the Plastigage at its widest point.

Standard Oil Clearance

Item	Specified Condition
Intake No. 1 journal	0.035 to 0.072 mm (0.00138 to 0.00283 in.)
Exhaust No. 1 journal	0.005 to 0.054 mm (0.000197 to 0.00213 in.)
Other journals	0.025 to 0.062 mm (0.000984 to 0.00244 in.)

Maximum Oil Clearance

Item	Specified Condition
Intake No. 1 journal	0.085 mm (0.00335 in.)
Exhaust No. 1 journal	0.085 mm (0.00335 in.)
Other journals	0.085 mm (0.00335 in.)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Plastigage
*b	No. 1 Journal
*c	Other Journals

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

INSPECT CAMSHAFT TIMING EXHAUST GEAR ASSEMBLY

Install the camshaft timing exhaust gear assembly to the No. 2 camshaft.
See step 4

Release the lock pin.

Clean the No. 2 camshaft journal with non-residue solvent.

Cover the 4 oil paths of the cam journal with vinyl tape as shown in the illustration.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Knock Pin
*b	Advance Side Path
*c	Retard Side Path
*d	Open
*e	Closed
	Rubber Piece
	Vinyl Tape

HINT:

There are 4 oil paths in the grooves of the No. 2 camshaft. Plug 2 oil paths with rubber pieces.

Make a hole in the tape over the 2 oil holes that are not plugged with rubber pieces.

Apply approximately 200 kPa (2.0 kgf/cm² , 29 psi) of air pressure to the 2 open paths (the advance side path and retard side path).

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Advance Side Path
*b	Retard Side Path

NOTE:

Cover the oil paths with a piece of cloth when applying air pressure to prevent oil from spraying.

Check that the camshaft timing exhaust gear assembly rotates in the retard direction when reducing the air pressure applied to the advance side path.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Advance Side Path
*b	Retard Side Path
*c	Hold Pressure
*d	Decompress

HINT:

This operation releases the lock pin for the most retarded position.

When the camshaft timing exhaust gear assembly moves to the most retarded position, release the air pressure from the advance side path, and then release the air pressure from the retard side path.
NOTE:
Do not release the air pressure from the retard side path first. The camshaft timing exhaust gear may abruptly shift in the advance direction and break the lock pin.

Check for smooth rotation.
1. Turn the camshaft timing exhaust gear assembly within its movable range (21.5 to 23.5°) 2 or 3 times, but do not turn it to the most advanced position. Make sure that the gear turns smoothly.
  NOTE:
  Do not use air pressure to perform the smooth operation check.
Remove the vinyl tape and rubber pieces from the No. 2 camshaft.
Remove the camshaft timing exhaust gear assembly from the No. 2 camshaft.
See step 25
Place the chain sub-assembly around the camshaft timing exhaust gear assembly.

Inspect the camshaft timing exhaust gear assembly diameter.

Using a vernier caliper, measure the camshaft timing exhaust gear assembly diameter with the chain sub-assembly.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Chain Sub-assembly Roller

Sprocket Diameter (with Chain Sub-assembly)

115.12 mm (4.53 in.)

HINT:

The vernier caliper must contact the chain sub-assembly rollers when measuring.

INSPECT CHAIN SUB-ASSEMBLY

Using a spring scale, pull the chain sub-assembly with a force of 147 N (15 kgf, 33 lbf) and measure the length of the chain sub-assembly using a vernier caliper.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Measuring Point

Using a vernier caliper, measure the length of 15 pins.
Maximum Chain Elongation

137.1 mm (5.40 in.)

HINT:

Perform the measurement at 3 random places.

If the elongation is more than the maximum, replace the chain sub-assembly.

INSPECT CRANKSHAFT TIMING SPROCKET

Place the chain sub-assembly around the crankshaft timing sprocket.

Using a vernier caliper, measure the crankshaft timing sprocket diameter with the chain sub-assembly.

Minimum Sprocket Diameter (with Chain Sub-assembly)

59.94 mm (2.36 in.)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If the diameter is less than the minimum, replace the chain sub-assembly and crankshaft timing sprocket.

HINT:

The vernier caliper must contact the chain sub-assembly rollers when measuring.

INSPECT NO. 1 CHAIN TENSIONER ASSEMBLY

Rotate the stopper plate counterclockwise to release the lock. Push the plunger and check that it moves smoothly.

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

*a	Stopper Plate
*b	Plunger

If the plunger does not move smoothly, replace the No. 1 chain tensioner assembly.

INSPECT CHAIN TENSIONER SLIPPER

Measure the depth of wear of the chain tensioner slipper.

Maximum Depth

1.0 mm (0.0394 in.)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Depth

If the depth is more than the maximum, replace the chain tensioner slipper.

INSPECT NO. 1 CHAIN VIBRATION DAMPER

Measure the depth of wear of the No. 1 chain vibration damper.

Maximum Depth

1.0 mm (0.0394 in.)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Depth

If the depth is more than the maximum, replace the No. 1 chain vibration damper.

INSPECT TIMING CHAIN GUIDE

Measure the depth of wear of the timing chain guide.

Maximum Depth

1.0 mm (0.0394 in.)

Depth

If the depth is more than the maximum, replace the timing chain guide.

INSPECT BALANCE SHAFT THRUST CLEARANCE

Inspect the No. 1 balance shaft thrust clearance.

Using a dial indicator, measure the thrust clearance while moving the No. 1 balance shaft back and forth.

Standard Thrust Clearance

0.07 to 0.11 mm (0.00276 to 0.00433 in.)

Maximum Thrust Clearance

0.11 mm (0.00433 in.)

If the thrust clearance is more than the maximum, replace the engine balancer assembly.

Inspect the No. 2 balance shaft thrust clearance.

Using a dial indicator, measure the thrust clearance while moving the No. 2 balance shaft back and forth.

Standard Thrust Clearance

0.07 to 0.11 mm (0.00276 to 0.00433 in.)

Maximum Thrust Clearance

0.11 mm (0.00433 in.)

If the thrust clearance is more than the maximum, replace the engine balancer assembly.

INSPECT BALANCE SHAFT BACKLASH

Secure the No. 2 balance shaft in place, and then, using a dial indicator, measure the backlash of the No. 1 and No. 2 balance shafts as shown in the illustration.

Standard Backlash

0.04 to 0.16 mm (0.00157 to 0.00630 in.)

Maximum Backlash

0.16 mm (0.00630 in.)

Secure

NOTE:

Measure at 3 or more areas around the circumference of the No. 1 and No. 2 balance shafts.

If the backlash is more than the maximum, replace the engine balancer assembly.

INSPECT CYLINDER HEAD SET BOLT

Using a vernier caliper, measure the diameter of the threads at the measuring point.

Measurement Point (Distance from the Seat)

106 mm (4.17 in.)

Standard Diameter

10.85 to 11.00 mm (0.427 to 0.433 in.)

Minimum Diameter

10.6 mm (0.417 in.)

*a	106 mm (4.17 in.)
*b	Measurement Point

If the diameter is less than the minimum, replace the cylinder head set bolt.

HINT:

If the diameter is less than the minimum, replace the cylinder head set bolt. Failure to do so may lead to engine damage.
If there is any thread deformation, replace the cylinder head set bolt with a new one.