Toyota
Yaris NCP90 91 92 93
Repair Manual
1Nz-Fe Engine Mechanical
Engine Unit
Check the lock of camshaft timing gear.
Clamp the camshaft in a vice, and check that the camshaft timing gear is locked.
- NOTICE:
- Do not damage the camshaft.

Release the lock pin.
Cover the 4 oil paths of the cam journal with tape as shown in the illustration.
- HINT:
- One of the 2 grooves located on the cam journal is for retarding cam timing (upper) and the other is for advancing cam timing (lower). Each groove has 2 oil paths. Plug one of the oil paths for each groove with a piece of rubber before wrapping the cam journal with the tape.
Puncture the tape covering the advance oil path and the retard oil path on the opposite side from the advance oil path.

Apply air at about 150 kPa (1.5 kgf*cm2) pressure into the 2 broken paths (the advance side path and the retard side path).
- NOTICE:
- Cover the paths with a shop rag or piece of cloth to prevent oil splashes.

Confirm that the camshaft timing gear assembly revolves in the timing advance direction when the air pressure on the timing retard path is reduced.
- HINT:
- The lock pin is released and the camshaft timing gear revolves in the advance direction.
When the camshaft timing gear reaches the most advanced position, release the air pressure on the timing retard side path, and then release the air pressure on the timing advance side path.
- NOTICE:
- Camshaft timing gear assembly occasionally shifts to the retard side abruptly if the air pressure on the advance side path is released first. This often results in the breakage of the lock pin.
Check the revolution.
Rotate the valve timing assembly back and forth several times, except where the lock pin meets it at the most retarded angle. Check the movable range and that it rotates smoothly.
- Standard:
- Smooth movable range is about 22.5°
- NOTICE:
- Perform this check by hand, instead of using air pressure.
Check the lock in the most retarded position.
Confirm that the camshaft timing gear assembly is locked in the most retarded position.
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Using a spring scale, apply 140 N (14.3 kgf, 31.5 lb) to the timing chain and measure its length.
- Maximum chain elongation:
- 123.2 mm (4.850 in.)
- HINT:
- Perform the same measurement at 3 or more random places and calculate the average length.
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Check that the plunger moves smoothly when the ratchet pawl is raised with your finger.
Release the ratchet pawl and check that the plunger is locked in place by the ratchet pawl and does not move when pushed with your finger.
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Wrap the chain around the timing sprocket.
Using vernier calipers, measure the diameter of the timing gear with the chain.
- Minimum gear diameter (with chain):
- 96.2 mm (3.787 in.)
- NOTICE:
- Make sure that the vernier calipers are in contact with the chain link when measuring.
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Wrap the chain around the timing sprocket.
Using vernier calipers, measure the diameter of the timing gear with the chain.
- Minimum gear diameter (with chain):
- 96.2 mm (3.787 in.)
- NOTICE:
- Make sure that the vernier calipers are in contact with the chain link when measuring.
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Check the chain tensioner slipper.
- Minimum thickness:
- 1.0 mm (0.039 in.)
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Check the vibration damper.
- Minimum thickness:
- 1.0 mm (0.039 in.)
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Using a dial indicator, measure the thrust clearance while moving the connecting rod back and forth.
- Standard thrust clearance:
- 0.16 to 0.36 mm (0.0063 to 0.0142 in.)
- Maximum thrust clearance:
- 0.36 mm (0.0142 in.)
Check that the matchmarks on the connecting rod and cap are aligned to ensure correct reassembly.

Using SST, remove the 2 connecting rod cap bolts.
- SST
- 09205-16011
Clean the crank pin and bearing.
Check the crank pin and bearing for pitting and scratches.

Lay a strip of Plastigage across the crank pin.

Make sure that the connecting rod and its cap are in the correct combination and that the front mark of the cap is facing in the correct mounting orientation, then install the cap onto the connecting rod.
Apply a light coat of engine oil to the threads of the connecting rod cap bolts.

Using SST, tighten the bolts in several steps to the specified torque.
- Torque:
- 15 N*m{153 kgf*cm, 11 ft.*lbf}
- SST
- 09205-16011

Mark the front of the connecting cap bolts with paint.
Retighten the cap bolts by 90° as shown in the illustration.
- NOTICE:
- Do not turn the crankshaft.
Remove the 2 bolts, connecting rod cap and lower bearing.

Measure the plastigage at its widest point.
- Standard oil clearance:
- 0.012 to 0.038 mm (0.00047 to 0.0015 in.)
- Maximum oil clearance:
- 0.058 mm (0.0028in.)
- NOTICE:
- Completely remove the plastigage after the measurement.

When replacing a bearing, replace it with one with the same number as marked on the connecting rod. There are 3 sizes of standard bearings, marked 1, 2 and 3 accordingly.
Standard bearing center wall thickness Mark mm (in.) 1 1.491 to 1.494 (0.0587 to 0.0588) 2 1.494 to 1.497 (0.0588 to 0.0589) 3 1.497 to 1.500 (0.0589 to 0.0591)
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Using a dial indicator, measure the thrust clearance while moving the crankshaft back and forth with a screwdriver.
- Standard thrust clearance:
- 0.09 to 0.19 mm (0.0035 to 0.0075 in.)
- Maximum thrust clearance:
- 0.30 mm (0.0118 in.)
- HINT:
- Thrust washer thickness: 2.43 to 2.48 mm (0.0957 to 0.976 in.)
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Using a precision straightedge and feeler gauge, measure the warpage of the surface which is in contact with the cylinder head gasket.
- Maximum warpage:
- 0.05 mm (0.0020 in.)
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Using a cylinder gauge, measure the cylinder bore diameter at positions A and B in the thrust and axial directions.
- Standard inside diameter:
- 75.000 to 75.013 mm (2.9528 to 2.9533 in.)
Calculate the difference between the maximum diameter and the minimum diameter of the 4 measured values.
- Difference limit:
- 0.10 mm (0.0039 in.)
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Using a micrometer, measure the piston diameter at a right angle to the piston pin center line, and at the position 27.6 to 27.8 mm (1.0866 to 1.0945 in.) from top of the piston head.
- Piston diameter:
- 74.935 to 74.945 mm (2.9502 to 2.9506 in.)
Using a caliper gauge, measure the piston pin hole diameter.
- Piston pin hole diameter:
- 18.013 to 18.016 mm (0.7092 to 0.7093 in.) at 20°C(68°F)

Using a micrometer, measure the piston pin diameter.
- Piston pin diameter:
- 18.001 to 18.004 mm (0.7087 to 0.7088 in.)
Subtract the piston pin diameter measurement from the piston pin hole diameter measurement to calculate the oil clearance.
- Standard oil clearance:
- 0.009 to 0.015 mm (0.0004 to 0.0006 in.)
- Maximum oil clearance:
- 0.050 mm (0.0020 in.)
Subtract the piston diameter measurement from the cylinder bore diameter measurement to calculate the oil clearance.
- Standard oil clearance:
- 0.045 to 0.068 mm (0.0018 to 0.0027 in.)
- Maximum oil clearance:
- 0.08 mm (0.0032 in.)
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Using a rod aligner and feeler gauge, check the connecting rod alignment.
Check for misalignment.
- Maximum misalignment:
- 0.05 mm (0.0020 in.) per 100 mm (3.94 in.)

Check for twist.
- Maximum twist:
- 0.05 mm (0.0020 in.) per 100 mm (3.94 in.)
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Using a feeler gauge, measure the clearance between a new piston ring and the wall of the ring groove.
- Ring groove clearance:
- No. 1:
- 0.03 to 0.07 mm (0.0012 to 0.0028 in.)
- No. 2:
- 0.02 to 0.06 mm (0.0008 to 0.0024 in.)
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Using a piston, push the piston ring, a little beyond the bottom of the ring travel, 110 mm (4.33 in.) from the top of the cylinder block.

Using a feeler gauge, measure the end gap.
- Standard end gap:
- No. 1:
- 0.25 to 0.35 mm (0.0098 to 0.0138 in.)
- No. 2:
- 0.35 to 0.50 mm (0.0138 to 0.0197 in.)
- Oil (Side Rail):
- 0.10 to 0.35 mm (0.0039 to 0.0138 in.)
- Maximum end gap:
- No. 1:
- 0.91 mm (0.0358 in.)
- No. 2:
- 1.06 mm (0.0417 in.)
- Oil (Side Rail):
- 0.82 mm (0.323 in.)
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Using vernier calipers, measure the diameter of the bolt at the elongated portion.
- Standard diameter:
- 6.6 to 6.7 mm (0.260 to 0.264 in.)
- Minimum diameter:
- 6.4 mm (0.252 in.)
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Using a dial indicator and V-blocks, measure the circle runout as shown in the illustration.
- Maximum circle runout:
- 0.03 mm (0.0012 in.)

Using a micrometer, measure the diameter of each main journal.
- Outside Diameter:
- 45.988 to 46.000 mm (1.8106 to 1.8110 in.)
Check each main journal for taper and out-of-roundness as shown.
- Maximum taper and out-of-roundness:
- 0.02 mm (0.0008 in.)

Using a micrometer, measure the diameter of each crank pin.
- Outside Diameter:
- 39.992 to 40.000 mm (1.5745 to 1.5748 in.)
Check each crank pin for taper and out-of-roundness as shown.
- Maximum taper and out-of-roundness:
- 0.02 mm (0.0008 in.)

Wrap the chain around the timing sprocket.
Using vernier calipers, measure the timing sprocket diameter with the chain.
- Standard sprocket diameter (with chain):
- 51.72 mm (2.0362 in.)
- Minimum sprocket diameter (with chain):
- 50.5 mm (1.988 in.)
- NOTICE:
- Make sure that the vernier calipers are in contact with the chain rollers when measuring.
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Using vernier calipers, measure the tension portion diameter at the elongated portion.
- Standard diameter:
- 7.3 to 7.5 mm (0.287 to 0.295 in.)
- Minimum diameter:
- 7.2 mm (0.283 in.)
Clean each main journal and bearing.
Install the bearing onto the cylinder block and bearing cap. (Click here)
Place the crankshaft onto the cylinder block.

Lay a strip of Plastigage across each journal.

Examine the front marks and numbers and install the bearing cap onto the cylinder block.
Apply a light coat of engine oil to the threads of the bearing cap bolts.

Using 12 mm socket wrench, tighten the bolts in several steps to the specified torque in the sequence shown in the illustration. (*1)
- Torque:
- 22 N*m{224 kgf*cm, 16 ft.*lbf}

Mark the front of the bearing cap bolts with paint.
Retighten the bearing cap bolts by 90° in the same sequence as step (*1).
Check that the painted mark is now at a 90° angle from the front.
- NOTICE:
- Do not turn the crankshaft.
Remove the bearing cap sub-assembly.

Measure the plastigage at its widest point.
- Standard oil clearance:
- 0.01 to 0.023 mm (0.0004 to 0.0009 in.)
- Maximum oil clearance:
- 0.07 mm (0.0028 in.)
- NOTICE:
- Completely remove the plastigage after the measurement.

When replacing a standard bearing, replace it with one with the same number. If the number of the bearing cannot be found on the bearing shell, select the correct bearing by adding together the numbers imprinted on the cylinder block and crankshaft, then select the bearing with the same number as the total. There are 4 sizes of standard bearings, marked 1, 2, 3 and 4 accordingly.
EXAMPLE: Cylinder Block 4 (A) + Crankshaft 3 (B) = Total No. 7 (Use Bearing 3) Cylinder Block (A)
+
Crankshaft (B)0 to 2 3 to 5 6 to 8 9 to 11 Use Bearing 1 2 3 4 Item Mark mm (in.) Cylinder block main journal bore diameter (A) 0
1
2
3
4
5
650.000 to 50.003 (1.96850 to 1.96862)
50.003 to 50.005 (1.96862 to 1.96870)
50.005 to 50.007 (1.96870 to 1.96878)
50.007 to 50.010 (1.96878 to 1.96890)
50.010 to 50.012 (1.96890 to 1.96898)
50.012 to 50.014 (1.96898 to 1.96906)
50.014 to 50.016 (1.96906 to 1.96913)Crankshaft main journal diameter (B) 0
1
2
3
4
545.998 to 46.000 (1.81094 to 1.81102)
45.996 to 45.998 (1.81087 to 1.81094)
45.994 to 45.996 (1.81079 to 1.81087)
45.992 to 45.994 (1.81071 to 1.81079)
45.990 to 45.992 (1.81063 to 1.81071)
45.988 to 45.990 (1.81055 to 1.81063)Standard bearing center wall thickness 1
2
3
41.992 to 1.995 (0.07843 to 0.07854)
1.995 to 1.998 (0.07854 to 0.07866)
1.998 to 2.001 (0.07866 to 0.07878)
2.001 to 2.004 (0.07878 to 0.07890)
















