Cylinder Block: Inspection

1. Remove the gasket material.

   Using a gasket scraper, remove all the gasket material from the top surface of the cylinder block.

   Fig 1: Using Scraper To Clean Top Of Cylinder Block

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Clean the cylinder block.

   Using a soft brush and solvent, thoroughly clean the cylinder block.

   NOTE: If the cylinder is washed at high temperatures, the cylinder liner sticks out beyond the cylinder block, so always wash the cylinder block at a temperature of 45°C (133°F) or less.

1. Inspect for flatness.

   Using a precision straight edge and a feeler gauge, measure the surface contacting the cylinder head gasket for warpage.

   Fig 2: Using Straight Edge To Check For Warpage

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Maximum warpage: 0.05 mm (0.0020 in.) 

   If warpage is greater than maximum, replace the cylinder block.

2. Visually check the cylinder for vertical scratches.
   Fig 3: Visually Inspecting For Cylinder Bore Scratches

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   If deep scratches are present, replace the cylinder block.

3. Inspect the cylinder bore diameter.

   Using a cylinder gauge, measure the cylinder bore diameter at positions A, B and C in the thrust and axial directions.

   Fig 4: Using Cylinder Gauge To Measure Bore

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Standard diameter: 
      1. 79.000 - 79.013 mm (3.1102 - 3.1107 in.) 
   2. Maximum diameter: 
      1. 79.013 mm (3.1107 in.) 

   If the diameter is greater than maximum, replace the cylinder block.

If the wear is less than 0.2 mm (0.008 in.), using a ridge reamer, grind the top of the cylinder.

Fig 5: Removing Ridge From Cylinder Bore

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Using vernier calipers, measure the tension portion diameter of the bolt.

Fig 6: Inspecting Bearing Cap Subassembly Bolts

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1. Standard diameter: 7.3 - 7.5 mm (0.287 - 0.295 in.) 
2. Minimum diameter: 7.3 mm (0.287 in.) 

If the diameter is less than minimum, replace the bolt.

1. Using a gasket scraper, remove the carbon from the piston top.
   Fig 7: Using Scraper To Clean Piston Top

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2. Using a groove cleaning tool or a broken ring, clean the piston ring grooves.
   Fig 8: Cleaning Piston Ring Grooves

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3. Using a brush and solvent, thoroughly clean the piston.
   Fig 9: Cleaning Piston With Brush & Solvent

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   NOTE: Do not use a wire brush.

1. Inspect the piston oil clearance.
   1. Using a micrometer, measure the piston diameter at right angles to the piston pin center line, 25.6 mm (1.008 in.) from the piston head.
      Fig 10: Measuring Piston Diameter

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      Piston diameter: 

      1. 78.925 - 78.935 mm (3.1073 - 3.1077 in.) 

   2. Measure the cylinder bore diameter in the thrust directions (See step  2).
   3. Subtract the piston diameter measurement from the cylinder bore diameter measurement.
      1. Standard oil clearance: 
         1. 0.065 - 0.088 mm (0.0026 - 0.0035 in.) 
      2. Maximum oil clearance: 
         1. 0.10 mm (0.0039 in.) 

      If the oil clearance is greater than maximum, replace all the 4 pistons. If necessary, replace the cylinder block.

2. Inspect the piston ring groove clearance.

   Using a feeler gauge, measure the clearance between a new piston ring and the wall of the ring groove.

   Fig 11: Measuring Piston Ring Groove Clearance

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Ring groove clearance: 
      1. 0.020 - 0.070 mm (0.0008 - 0.0028 in.) 

   If the clearance is not as specified, replace the piston.

3. Inspect the piston ring end gap.
   1. Insert the piston ring into the cylinder bore.
   2. Using the 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.
      Fig 12: Pushing Ring To Proper Depth For Measuring End Gap

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   3. Using a feeler gauge, measure the end gap.
      Fig 13: Measuring Piston Ring End Gap

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      Fig 14: Standard Ring End Gap

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      Fig 15: Minimum Ring End Gap

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      If the end gap is greater than maximum, replace the piston ring. If the end gap is greater than maximum, even with a new piston ring, replace the cylinder block.

4. Inspect the piston pin fit.
   Fig 16: Checking Piston Pin Fit

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   At 80 - 90°C (176 - 194°F), you should be able to push the piston pin into the piston pin hole with your thumb.

1. Using a rod aligner and a feeler gauge, check the connecting rod alignment.
   Fig 17: Checking For Connecting Rod Out Of Alignment

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   1. Check for out-of-alignment.

      Maximum out-of-alignment: 

      1. 0.05 mm (0.0020 in.) per 100 mm (3.94 in.) 

      If out-of-alignment is greater than maximum, replace the connecting rod assembly.

   2. Check for twist.
      Fig 18: Checking For Connecting Rod Twist

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      Maximum twist: 

      1. 0.05 mm (0.0020 in.) per 100 mm (3.94 in.) 

      If twist is greater than maximum, replace the connecting rod assembly.

2. Inspect the piston pin oil clearance.
   1. Using a caliper gauge, measure the inside diameter of the connecting rod bushing.
      Fig 19: Measuring Connecting Rod Bushing Inside Diameter

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Bushing inside diameter: 

      1. 20.012 - 20.021 mm (0.7879 - 0.7882 in.) 

   2. Using a micrometer, measure the piston pin diameter.
      Fig 20: Measuring Piston Pin Diameter

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Piston pin diameter: 

      1. 20.004 - 20.013 mm (0.7876 - 0.7879 in.) 

   3. Subtract the piston pin diameter measurement from the bushing inside diameter measurement.
      1. Standard oil clearance: 
         1. 0.005 - 0.011 mm (0.0002 - 0.0004 in.) 
      2. Maximum oil clearance: 
         1. 0.05 mm (0.0020 in.) 

      If the oil clearance is greater than maximum, replace the bushing. See REPLACEMENT . If necessary, replace the piston and piston pin as a set.

Using vernier calipers, measure the tension portion diameter of the bolt.

Fig 21: Checking Connecting Rod Bolts

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Standard diameter: 6.6 - 6.7 mm (0.260 - 0.264 in.) 

Minimum diameter: 6.4 mm (0.252 in.) 

If the diameter is less than minimum, replace the bolt.

1. Inspect for circle runout.
   1. Place the crankshaft on V-blocks.
   2. Using a dial indicator, measure the circle runout.
      Fig 22: Measuring Crankshaft Circle Runout

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Maximum circle runout: 0.03 mm (0.0012 in.) 

      If the circle runout is greater than maximum, replace the crankshaft.

2. Inspect the main journals and crank pins.
   1. Using a micrometer, measure the diameter of each main journal and crank pin.
      Fig 23: Measuring Journal Diameters

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      Diameter: 

      1. Main Journal: 47.988-48.000 mm (1.8893-1.8898 in.) 
      2. Crank Pin: 43.992-44.000 mm (1.7320-1.7323 in.) 

      If the diameter is not as specified, check the oil clearance. See DISASSEMBLY . If necessary, replace the crankshaft.

   2. Check each main journal and crank pin for taper and out-of-round as shown in Fig 23.

      Maximum taper and out-of-round: 

      1. 0.02 mm (0.0008 in.) 

      If the taper and out-of-round is greater than maximum, replace the crankshaft.