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Piston Fitting

WARNING: This page is about a different car, the 2012 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Measuring Cylinder Bore Diameter
GC0086020Courtesy of CHRYSLER GROUP, LLC
1 - FRONT
2 - BORE GAUGE
3 - CYLINDER BORE
4 - 38 MM
(1.5 in)
  1. To correctly select the proper size piston, a cylinder bore gauge (2), capable of reading in 0.003 mm (.0001 in.) INCREMENTS is required. If a bore gauge is not available, do not use an inside micrometer. Refer to Fig 1.
  2. Measure the inside diameter of the cylinder bore (3) at a point 38.0 mm (1.5 inches) below top of bore. Start perpendicular (across or at 90 degrees) to the axis of the crankshaft at point A and then take an additional bore reading 90 degrees to that at point B.
    Fig 2: Moly Coated Piston
    GC0082866Courtesy of CHRYSLER GROUP, LLC
    1 - MOLY COATED
    2 - MOLY COATED
  3. The coated pistons (1, 2) will be serviced with the piston pin and connecting rod pre-assembled. Refer to Fig 2.
  4. The coating material is applied to the piston after the final piston machining process. Measuring the outside diameter of a coated piston (1, 2) will not provide accurate results. Therefore measuring the inside diameter of the cylinder bore with a dial Bore Gauge is MANDATORY  . To correctly select the proper size piston, a cylinder bore gauge capable of reading in 0.003 mm (.0001 in.) increments is required.
  5. Piston installation into the cylinder bore requires slightly more pressure than that required for non-coated pistons. The bonded coating on the piston will give the appearance of a line-to-line fit with the cylinder bore.