Inspect the dimensions of the piston carefully: there must be no signs of shrinkage, scoring, cracks or damage.
The diameter of the piston (D1) must be measured at 10 mm/0.39 in. from the skirt base, at right angles to the axis of the gudgeon pin.
Note.
- The pistons are marked by a letter which indicates the class they belong to (printed on the crown of the piston).
- The pistons must always be changed in pairs.
Piston-cylinder coupling
Coupling clearance (D-D1): 0.025-0.045 mm / 0.00098-0.00177 in.
Maximum clearance: 0.12 mm/0.00472 in.
Note. The cylinder-piston coupling must only be made with cylinders and pistons belonging to the same class.
