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Cylinder Block: Inspection

  1. CLEAN CYLINDER BLOCK 
    1. Remove the gasket material.

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

      Fig 1: Removing All Gasket Material From Cylinder Block Surface
      G02948521Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Clean the cylinder block.

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

  2. INSPECT CYLINDER BLOCK SURFACE FOR FLATNESS 

    Using precision straight edge and feeler gauge, measure the top surfaces of the cylinder block for warpage.

    Maximum warpage: 0.07 mm (0.0028 in.) 

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

    Fig 2: Using Precision Straight Edge And Feeler Gauge To Measure Top Surfaces Of Cylinder Block For Warpage
    G02948522Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT CYLINDER FOR VERTICAL SCRATCHES 

    Visually check the cylinder for vertical scratches.

    If deep scratches are present, replace the cylinder block.

    Fig 3: Inspecting Cylinder For Vertical Scratches
    G02948523Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. INSPECT CYLINDER BORE DIAMETER 

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

    Standard diameter: 

    86.000-86.013 mm (3.3858-3.3863 in.) 

    Maximum diameter: 86.02 mm (3.3866 in.) 

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

    Fig 4: Identifying Cylinder Bore Diameter Measuring Position
    G02948524Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. REMOVE CYLINDER RIDGE 

    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 Cylinder Ridge
    G02948525Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. INSPECT MAIN BEARING CAP BOLTS 

    Using vernier calipers, measure the minimum diameter of the compressed thread at the measuring point.

    Standard diameter: 

    9.96-9.97 mm (0.3921-0.3925 in.) 

    Minimum diameter: 9.7 mm (0.382 in.) 

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

    Fig 6: Measuring Minimum Diameter Of Compressed Thread At Measuring Point
    G02948526Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. CLEAN PISTON 
    1. Using a gasket scraper, remove the carbon from the piston top.
      Fig 7: Removing Carbon From Piston Top
      G02948527Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a groove cleaning tool or broken ring, clean the piston ring grooves.
    3. Fig 8: Cleaning Piston Ring Grooves
      G02948528Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Using solvent and a brush, thoroughly clean the piston.
    NOTE: Do not use a wire brush.
  8. INSPECT PISTON OIL CLEARANCE 
    1. Using a micrometer, measure the piston diameter at right angles to the piston pin center line, 34 mm (1.34 in.) from the piston head.

      Piston diameter: 

      85.945-85.965 mm (3.3837-3.3844 in.) 

      Fig 9: Measuring Piston Diameter At Right Angles To Piston Pin Center Line
      G02948529Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the cylinder bore diameter in the thrust directions (See step  4).
    3. Subtract the piston diameter measurement from the cylinder bore diameter measurement.

      Standard oil clearance: 

      0.035-0.068 mm (0.0014-0.0027 in.) 

      Maximum oil clearance: 0.10 mm (0.0039 in.) 

    If the oil clearance is greater than maximum, replace all the 6 pistons. If necessary, replace the cylinder block.

  9. INSPECT PISTON RING GROOVE CLEARANCE 

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

    Ring groove clearance: 

    PISTON RING GROOVE CLEARANCE SPECIFICATION

    No.1 0.011-0.070 mm (0.0004-0.0028 in.)
    No.2 0.030-0.070 mm (0.0012-0.0028 in.)

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

    Fig 10: Measuring Clearance Between New Piston Ring And Wall Of Piston Ring Groove
    G02948530Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  10. INSPECT PISTON RING END GAP 
    1. Insert the piston ring into the cylinder bore.
    2. Using a piston, push the piston ring a little beyond the bottom of the ring travel, 105 mm (4.13 in.) from the top of the cylinder block.
      Fig 11: Using Piston To Push Piston Ring Little Beyond Bottom Of Ring Travel
      G02948531Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using a feeler gauge, measure the ring end gap.
    4. Fig 12: Measuring Ring End Gap
      G02948532Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard ring end gap: 

    STANDARD RING END GAP SPECIFICATION

    No.1 0.300-0.470 mm (0.0118-0.0185 in.)
    No.2 0.350-0.520 mm (0.0138-0.0205 in.)
    Oil (Side rail) 0.130-0.450 mm (0.0051-0.0177 in.)

    Maximum ring end gap: 

    MAXIMUM RING END GAP SPECIFICATION

    No.1 1.07 mm (0.0421 in.)
    No.2 1.12 mm (0.0441 in.)
    Oil (Side rail) 1.05 mm (0.0413 in.)

    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.

  11. INSPECT PISTON PIN FIT 

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

    Fig 13: Inspecting Piston Pin Fit
    G02948533Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  12. INSPECT CONNECTING ROD ALIGNMENT 

    Using a feeler gauge and rod aligner, check the connecting rod alignment.

    • Check for out-of-alignment.

      Maximum out-of-alignment: 

      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.

      Fig 14: Checking Connecting Rod Alignment (For Out-Of-Alignment)
      G02948534Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    • Check for twist.

      Maximum twist: 

      0.15 mm (0.0059 in.) per 100 mm (3.94 in.) 

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

      Fig 15: Checking Connecting Rod Alignment (For Twist)
      G02948535Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  13. INSPECT PISTON PIN OIL CLEARANCE 
    1. Using a caliper gauge, measure the inside diameter of the connecting rod bushing.

      Bushing inside diameter: 

      22.005-22.014 mm (0.8663-0.8667 in.) 

      Fig 16: Measuring Inside Diameter Of Connecting Rod Bushing
      G02948536Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using a micrometer, measure the piston pin diameter.

      Piston pin diameter: 

      21.997-22.006 mm (0.8660-0.8664 in.) 

      Fig 17: Measuring Piston Pin Diameter
      G02948537Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Subtract the piston pin diameter measurement from the bushing in side diameter measurement.

      Standard oil clearance: 

      0.005-0.011 mm (0.0002-0.0004 in.) 

      Maximum oil clearance: 0.05 mm (0.0020 in.) 

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

  14. INSPECT CONNECTING ROD BOLTS 

    Using vernier calipers, measure the minimum diameter of the compressed bolt at the measuring point.

    Standard diameter: 8.1-8.3 mm (0.319-0.327 in.) 

    Minimum diameter: 8.0 mm (0.315 in.) 

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

    Fig 18: Using Vernier Calipers To Measure Minimum Diameter Of Compressed Bolt At Measuring Point
    G02948538Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  15. INSPECT CRANKSHAFT FOR RUNOUT 
    1. Place the crankshaft on V-blocks.
    2. Using a dial indicator, measure the circle runout at the center journal.

      Maximum circle runout: 0.06 mm (0.0024 in.) 

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

      Fig 19: Using Dial Indicator To Measure Circle Runout At Center Journal
      G02948539Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  16. INSPECT MAIN JOURNALS AND CRANK PINS 
    1. Using a micrometer, measure the diameter of each main journal and crank pin.
      Fig 20: Measuring Diameter Of Each Main Journal And Crank Pin
      G02948540Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Main journal diameter: 

      MAIN JOURNAL DIAMETER SPECIFICATION

      STD 61.984-62.000 mm (2.4403-2.4409 in.)
      U/S 0.25 61.745-61.755 mm (2.4309-2.4313 in.)

      Crank pin diameter: 

      CRANK PIN DIAMETER SPECIFICATION

      STD 51.982-52.000 mm (2.0465-2.0472 in.)
      U/S 0.25 51.745-51.755 mm (2.0372-2.0376 in.)

      If the diameter is not as specified, check the oil clearance (See DISASSEMBLY ).

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

      Maximum taper and out-of round: 

      0.02 mm (0.0008 in.) 

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

  17. IF NECESSARY, GRIND AND HONE MAIN JOURNALS AND/OR CRANK PINS 
    • Grind and hone the main journals and/or crank pins to the finished undersized diameter (See procedure step  b).
    • Install new main journal and/or crank pin undersized bearings.