Engine Unit Repair


  1. BORE CYLINDER

Engine Unit -- Repair


HINT:
  1. Bore all the 4 cylinder to fit the O/S piston outside diameter.
  2. Replace all the piston rings with ones to match the O/S pistons.


1. BORE CYLINDER

  1. Prepare 4 new O/S pistons.

    O/S 0.50 piston diameter:
    99.950 to 99.980 mm (3.9350 to 3.9362 in.)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Mechanical.Engine Unit.Engine Unit Repair

  1. Using a micrometer, measure the piston diameter at right angles to the piston pin center line where the distance from the piston head is as specified.

    Standard distance:
    61.27 to 61.33 mm (2.4122 to 2.4146 in.)

  1. Calculate the amount each cylinder is to be rebored as follows.

    HINT:
    1. Size to be rebored = P + C - H
    2. P = Piston diameter
    3. C = Piston clearance: 0.040 to 0.060 mm (0.0016 to 0.0024 in.)
    4. 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.