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Cylinder Block: Disassembly

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECT CONNECTING ROD THRUST CLEARANCE 
    1. Using a dial indicator, measure the thrust clearance while moving the connecting rod back and forth

      Standard thrust clearance: 

      0.15 to 0.55 mm (0.00591 to 0.0217 in.) 

      Maximum thrust clearance: 

      0.70 mm (0.0276 in.) 

      If the thrust clearance is greater than the maximum, replace connecting rods as necessary If necessary, replace the crankshaft

      Fig 1: Measuring Connecting Rod Thrust Clearance
      G04943501Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT CONNECTING ROD OIL CLEARANCE 
    1. Check that the marks on the connecting rod and cap are aligned to ensure correct reassembly.
      NOTE: When installing the caps, the marks on bank 1 cylinders (1, 3, 5, 7) face towards the front of the engine and bank 2 cylinders (2, 4, 6, 8) face towards the rear of the engine.
      Fig 2: Identifying Marks On Connecting Rod And Cap
      G05749818Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Remove the 2 connecting rod cap bolts
      Fig 3: Removing Connecting Rod Cap Bolts
      G05749819Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using the 2 removed connecting rod cap bolts, remove the connecting rod cap and lower bearing by wiggling the connecting rod cap right and left

      HINT.

      Keep the lower bearing inserted to the connecting rod cap

    4. Clean the crank pin and bearing
      NOTE: Check the crank pin and bearing for pitting and scratches.
      Fig 4: Removing Connecting Rod Cap And Lower Bearing
      G05749820Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Lay a strip of Plastigage on the crank pin.
      Fig 5: Laying Strip Of Plastigage On Crank Pin
      G04943504Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Check that the mark of the connecting rod cap is facing the correct direction.
      NOTE: Be sure to assemble the bank 2 rods with the marks facing towards the rear of the engine.
      Fig 6: Identifying Mark Of Connecting Rod Cap
      G05749822Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    7. Install and alternately tighten the bolts of the connecting rod cap in several steps.

      Torque: 40 N*m (408 kgf*cm, 30 ft.*lbf) 

      NOTE: Do not turn the crankshaft.
    8. Mark the front side of each connecting cap bolt with paint.
      Fig 7: Tightening Connecting Cap Bolts
      G04943506Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    9. Retighten the cap bolts 90° as shown in the illustration.
    10. Check that the painted marks are now at a 90° angle to the front.
      NOTE: Do not turn the crankshaft.
      Fig 8: Identifying Retightening Angle Of Connecting Cap Bolts
      G04943507Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    11. Remove the 2 connecting rod cap bolts.
    12. Using the 2 removed connecting rod cap bolts, remove the connecting rod cap and lower bearing by wiggling the connecting rod cap right and left.

      HINT.

      Keep the lower bearing inserted to the connecting rod cap

    13. Measure the Plastigage at its widest point

      Standard oil clearance: 

      0.037 to 0.062 mm (0.00146 to 0.00244 in.) 

      Maximum oil clearance: 

      0.080 mm (0.00315 in.) 

      If the oil clearance is greater than the maximum, replace the bearings If necessary, replace the crankshaft.

      HINT

      • If replacing a bearing, replace it with one that has the same number as its respective connecting rod cap. Each bearing's standard thickness is indicated by a 1, 2, 3 or 4 mark on its surface.
      • Select the correct bearing by adding together the number marks imprinted on the connecting rod big end and crank pin

      Example

      Connecting rod "1" + Crank pin "2" = 3 (Use bearing "3")

      Reference

      Fig 9: Measuring Plastigage
      G05749825Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Sized Bearing Center Wall Thickness 

      BEARING CENTER WALL THICKNESS SPECIFICATION

      Mark Thickness
      2 1 483 to 1.486 mm (0 0584 to 0.0585 in.)
      3 1.486 to 1 489 mm (0.0585 to 0.0586 in.)
      4 1.489 to 1.492 mm (0.0586 to 0.0587 in.)
      5 1 492 to 1.495 mm (0.0587 to 0 0589 in.)
      6 1.495 to 1.498 mm (0 0589 to 0.0590 in.)
      7 1 498 to 1.501 mm (0.0590 to 0.0591 in.)

      Connecting Rod Big End Inside Diameter 

      CONNECTING ROD BIG END INSIDE DIAMETER SPECIFICATION

      Mark Thickness
      1 56.000 to 56 006 mm (2.2047 to 2.2050 in.)
      2 56 007 to 56 012 mm (2.2050 to 2.2052 in.)
      3 56 013 to 56.018 mm (2 2052 to 2.2054 in)
      4 56 019 to 56.024 mm (2 2055 to 2.2057 in)

      Crankshaft Pin Diameter 

      CRANKSHAFT PIN DIAMETER SPECIFICATION

      Mark Thickness
      1 52.995 to 53.000 mm (2.0864 to 2.0866 in.)
      2 52.989 to 52.994 mm (2.0862 to 2.0864 in.)
      3 52.982 to 52 988 mm (2.0859 to 2.0861 in.)
    14. Completely remove the Plastigage
    15. Perform the inspection above for each cylinder.
  3. REMOVE PISTON AND CONNECTING ROD 
    1. Using a ridge reamer, remove all the carbon from the top of the cylinder.
    2. Remove the 16 cap bolts and 8 connecting rod caps
    3. Push the 8 pistons, 8 connecting rods and 8 upper bearings through the top of the cylinder block.

      HINT

      • Keep each bearing, connecting rod and cap together.
      • Arrange the pistons and connecting rods in the correct order.
      Fig 10: Removing Carbon From Top Of Cylinder
      G04943509Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. REMOVE CONNECTING ROD BEARING 
    1. Remove the connecting rod bearings from the connecting rods and connecting rod caps.

      HINT

      Arrange the removed parts in the correct order.

  5. INSPECT CRANKSHAFT THRUST CLEARANCE 
    1. Using a dial indicator, measure the thrust clearance while prying the crankshaft back and forth with a screwdriver.

      Standard thrust clearance: 

      0.020 to 0.220 mm (0.000787 to 0.00866 in.) 

      Maximum thrust clearance: 

      0.30 mm (0.0118 in.) 

      If the thrust clearance is greater than the maximum, replace the thrust washers as a set If necessary, replace the crankshaft.

      Fig 11: Measuring Crankshaft Thrust Clearance
      G04943510Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard thrust washer thickness: 

      2.44 to 2.49 mm (0.0961 to 0.0980 in.) 

  6. REMOVE CRANKSHAFT 
    1. Using several steps, uniformly loosen and remove the 10 bearing cap bolts and 10 seal washers in the sequence shown the illustration
      Fig 12: Locating Loosening Sequence Of Bearing Cap Bolts
      G04943511Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Using several steps, uniformly loosen the 20 bearing cap bolts in the sequence shown in the illustration.
      Fig 13: Locating Loosening Sequence Of Bearing Cap Bolts
      G04943512Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Using a screwdriver, pry out the main bearing caps. Remove the 5 main bearing caps and lower bearings
      NOTE:
      • Pry up the main bearing caps gradually and evenly in turns.
      • Be careful not to damage the joint surface between the cylinder block and main bearing caps.

      HINT:

      Tape the screwdriver tip before use

    4. Remove the crankshaft.
    Fig 14: Removing Main Bearing Caps And Lower Bearings
    G04943513Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. REMOVE CRANKSHAFT THRUST WASHER SET 
    1. Remove the thrust washer set from the cylinder block and No. 3 bearing cap
  8. REMOVE CRANKSHAFT BEARING 
    1. Remove the crankshaft bearings from the bearing caps and cylinder block

      HINT

      Arrange the removed parts in the correct order.

    Fig 15: Locating Crankshaft Thrust Washers
    G05749831Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. REMOVE NO. 1 OIL NOZZLE SUB-ASSEMBLY 
    1. Using a 5 mm hexagon wrench, remove the 4 bolts and 4 oil nozzles.
  10. REMOVE PISTON RING SET 

    HINT

    Arrange the piston rings in the correct order.

    Fig 16: Locating Oil Nozzle Bolt
    G04943515Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Using a piston ring expander, remove the 2 compression rings.
    2. Using a piston ring expander, remove the oil ring.
    3. Remove the oil ring expander by hand.
      Fig 17: Removing Compression Rings And Oil Ring
      G05749833Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  11. REMOVE PISTON WITH PIN SUB-ASSEMBLY 
    1. Disconnect the connecting rod from the piston.
      1. Using a screwdriver, pry off the snap rings from the piston.
        Fig 18: Removing Snap Rings From Piston
        G05749834Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Using a brass bar and plastic-faced hammer, lightly tap out the piston pin and remove the connecting rod.

        HINT:

        • The piston and pin are a matched set.
        • Arrange the pistons, pins, rings, connecting rods and bearings in the correct order.
        Fig 19: Tapping Out Piston Pin
        G05749835Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Clean the piston.
      1. Using a gasket scraper, remove the carbon from the piston top
        Fig 20: Removing Carbon From Piston Top
        G04943520Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Using a groove cleaning tool or broken ring, clean the piston ring grooves
        Fig 21: Cleaning Piston Ring Grooves
        G04943521Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Using solvent and a brush, thoroughly clean the piston.
        NOTE: Do not use a wire brush.
        Fig 22: Cleaning Piston
        G04943522Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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