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Disassembly [03/2024 - ]: Procedure

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  1. REMOVE VALVE SPRING RETAINER LOCK 
    1. GTY1077067Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using SST, remove the 16 valve spring retainer locks.
        • SST: 09202-70020 
          1. 09202-01010
          2. 09202-01020
        • SST: 09202-00021 
  2. REMOVE VALVE SPRING RETAINER 
    1. GTY1076586Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. REMOVE INTAKE VALVE COMPRESSION SPRING 
    1. GTY1076587Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. REMOVE EXHAUST VALVE COMPRESSION SPRING 
    1. Perform the same procedure as for the intake valve compression spring.
  5. REMOVE INTAKE VALVE 
    1. GTY1077459Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  6. REMOVE EXHAUST VALVE 
    WARNING:
    • The exhaust valve is filled with sodium. Sodium is a strong alkali which may produce a dangerous chemical reaction. Therefore, be very careful when handling and disposing of it.
    • Do not disassemble the exhaust valve for the following reasons: 1) If sodium enters your eyes, vision loss may occur. 2) If sodium contacts your skin, burns may occur. 3) If sodium is exposed to a flame and starts a fire due to the chemical reaction that takes place, burns may occur.
    • If the exhaust valve is damaged, remove the valve and perform the proper procedures to dispose of the sodium. (disposal preparation and actual disposal)
    • When removing a damaged exhaust valve, always wear rubber gloves and safety glasses.
    • Do not cut the exhaust valve to take out the sodium.
    HINT: 
    • The sodium inside the exhaust valve is safe as long as the sodium is not exposed to air.
    • Exhaust valves filled with sodium can be identified by confirming the "NA" identification mark.
    1. Perform the same procedure as for the intake valve.
  7. REMOVE INTAKE VALVE STEM OIL SEAL 
    1. GTY1076483Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using needle-nose pliers, remove the 8 intake valve stem oil seals.
  8. REMOVE EXHAUST VALVE STEM OIL SEAL 
    1. Perform the same procedure as for the intake valve stem oil seal.
  9. REMOVE INTAKE VALVE SPRING SEAT 
    1. GTY1077300Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using compressed air and a Magnet Hand, remove the 8 intake valve spring seats from the cylinder head sub-assembly by blowing air onto them.
  10. REMOVE EXHAUST VALVE SPRING SEAT 
    1. Perform the same procedure as for the intake valve spring seat.
  11. REMOVE NO. 1 WITH HEAD STRAIGHT SCREW PLUG 
    NOTE:

    If coolant leaks from a No. 1 with head straight screw plug or a plug is corroded, replace it.

    1. GTY1078587Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using a 14 mm straight hexagon wrench, remove the No. 1 with head straight screw plug and gasket from the cylinder head sub-assembly.
  12. REMOVE NO. 2 WITH HEAD STRAIGHT SCREW PLUG 
    NOTE:

    If coolant leaks from a No. 2 with head straight screw plug or a plug is corroded, replace it.

    1. GTY1077779Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using a 14 mm straight hexagon wrench, remove the No. 2 with head straight screw plug and gasket from the cylinder head sub-assembly.
  13. REMOVE NO. 3 WITH HEAD STRAIGHT SCREW PLUG 
    NOTE:

    If coolant leaks from a No. 3 with head straight screw plug or a plug is corroded, replace it.

    1. GTY1077908Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using a 6 mm hexagon socket wrench, remove the 3 No. 3 with head straight screw plugs from the cylinder head sub-assembly.
  14. REMOVE STUD BOLT 
    NOTE:

    If a stud bolt is deformed or its threads are damaged, replace it.

    1. GTY1076690Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Using an E10 "TORX" socket wrench, remove the 4 stud bolts.
      2. Using an E8 "TORX" socket wrench, remove the 2 stud bolts.
  15. DISPOSE OF EXHAUST VALVE 
    WARNING:
    • The exhaust valve is filled with sodium. Sodium is a strong alkali which may produce a dangerous chemical reaction. Therefore, be very careful when handling and disposing of it.
    • Do not disassemble the exhaust valve for the following reasons: 1) If sodium enters your eyes, vision loss may occur. 2) If sodium contacts your skin, burns may occur. 3) If sodium is exposed to a flame and starts a fire due to the chemical reaction that takes place, burns may occur.
    • If the exhaust valve is damaged, remove the valve and perform the proper procedures to dispose of the sodium. (disposal preparation and actual disposal)
    • When removing a damaged exhaust valve, always wear rubber gloves and safety glasses.
    • Do not cut the exhaust valve to take out the sodium.
    NOTE:

    If it is clearly stated that the industrial waste disposal method is dissolution, carry out the process below.

    HINT: 

    • The sodium inside the exhaust valve is safe as long as the sodium is not exposed to air.
    • Exhaust valves filled with sodium can be identified by confirming the "NA" identification mark.
    1. Waste disposal preparation
      WARNING:

      Always carry out the following when performing the disposal procedure.

      1. Have a fire extinguisher close by.
      2. Wear safety glasses.
      3. Wear rubber gloves.
    2. Waste disposal
      1. Put on rubber gloves and remove the damaged exhaust valve from the cylinder head sub-assembly.
      2. Add 10 L of water or more to a large receptacle (a bucket, oil can, etc.) in a well ventilated area.
      3. Hold the damaged exhaust valve upright with pliers or large pair of tweezers and submerge it into the water.
        WARNING:
        • Fully submerge the damaged exhaust valve in water.
        • Do not allow any sparks or other flames near the receptacle as hydrogen gas is generated by the chemical reaction.
        • Stay 2 m (6.56 ft.) or 3 m (9.84 ft.) or more away from the receptacle as a strong chemical reaction occurs.
  16. REMOVE INTAKE VALVE GUIDE BUSH 
    1. GTY1073156Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      1. Heat the cylinder head sub-assembly to between 80 and 100°C (176 and 212°F).
        WARNING:

        Be sure to wear protective gloves.

      2. Using SST and a hammer, tap out the intake valve guide bush.
        • SST: 09201-01055 
        • SST: 09950-70010 
          1. 09951-07100
  17. REMOVE EXHAUST VALVE GUIDE BUSH 
    1. Perform the same procedure as for the intake valve guide bush.
  18. REMOVE RING PIN 
    NOTE:

    It is not necessary to remove the ring pins unless they are being replaced.

    1. GTY1076829Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002