Engine Unit Repair


  1. REPAIR INTAKE VALVE SEAT

  2. REPAIR EXHAUST VALVE SEAT

  3. BORE CYLINDER

Engine Unit -- Repair



1. REPAIR INTAKE VALVE SEAT
NOTICE:
Keep the lip free from foreign matter.


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. Apply a light coat of Prussian blue to the valve face.

  1. Lightly press the valve face against the valve seat.

  1. Check the valve seat according to the following procedures.

    1. If blue appears 360° around the valve face, the valve face is concentric. If not, replace the valve.

    2. If blue appears 360° around the valve seat, the guide and valve face are concentric. If not, resurface the valve seat.

    3. Check that the valve seat contact is in the middle of the valve face with the width between 1.0 to 1.4 mm (0.039 to 0.055 in.).



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. If the seating is too high on the valve face, use 30° and 45° cutters to correct the seat.



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. If the seating is too low on the valve face, use 60° and 45° cutters to correct the seat.

  1. Hand-lap the valve and valve seat with an abrasive compound.

  1. Check the valve seating position.



2. REPAIR EXHAUST VALVE SEAT
NOTICE:
Keep the lip free from foreign matter.


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. Apply a light coat of Prussian blue to the valve face.

  1. Lightly press the valve face against the valve seat.

  1. Check the valve seat according to the following procedures.

    1. If blue appears 360° around the valve face, the valve face is concentric. If not, replace the valve.

    2. If blue appears 360° around the valve seat, the guide and valve face are concentric. If not, resurface the valve seat.

    3. Check that the valve seat contact is in the middle of the valve face with the width between 1.0 to 1.4 mm (0.039 to 0.055 in.).



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. If the seating is too high on the valve face, use 30° and 45° cutters to correct the seat.



    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. If the seating is too low on the valve face, use 60° and 45° cutters to correct the seat.

  1. Hand-lap the valve and valve seat with an abrasive compound.

  1. Check the valve seating position.



3. BORE CYLINDER
HINT:
  1. Bore all 4 cylinders for the O/S piston outside diameter.
  2. Replace all the piston rings with ones to match the O/S pistons.


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.2Tr-Fe Engine Mechanical.Engine Unit.Engine Unit Repair

  1. Prepare 4 new O/S pistons.

    O/S 0.50 piston diameter:
    95.441 to 95.451 mm (3.7575 to 3.7579 in.)

  1. Using a micrometer, measure the piston diameter at right angles to the piston center line, at the indicated distance from the piston end.

    Standard distance:
    11.4 mm (0.449 in.)

  1. Calculate how much each cylinder needs to be rebored:

    Size to be rebored = P + C - H:
    P = Piston diameter
    C = Piston clearance: 0.019 to 0.052 mm (0.0007 to 0.0020 in.)
    H = Allowance for honing: 0.02 mm (0.0008 in.) or less

  1. Bore and hone the cylinders to the calculated dimensions.

    Maximum honing:
    0.02 mm (0.0008 in.)
    NOTICE:
    Excess honing will destroy the finished roundness.