Tools Porsche Cayenne S I

Tools

Scheme 277

1 - Three piston rings (lowest is the oil scraper ring)

2 - Piston (arrow on piston crown points in direction of travel)

3 - Two piston-pin circlips

4 - Piston pin

5 - Connecting rod and connecting-rod bearing cap

6 - Two connecting rod bolts

7 - Two bearing shells

Scheme 278

Markings on piston crown: Replacement pistons from Porsche Parts Service are only obtainable in one dimensional group 'X' and in two weight tolerances '+' and '-' . The weight tolerances are listed in the table.

1. Marking X appears as a large colored stamp in the center of the piston crown and as a small engraved feature (Scheme 278) -1-.
2. Marking + or - appears as a large colored stamp in the center of the piston crown and as a small engraved feature (Scheme 278) -2-.

Note. Pistons are installed as standard in three dimensional groups: I, X and II . Pistons are installed as standard in two weight tolerances: + and - . These data are all engraved on the piston crown. To uniquely identify a piston, it must be carefully cleaned (brass brush, ultrasonic bath). If, in spite of very thorough cleaning, the data are unreadable, the piston must be weighed together with piston rings, piston pin and the two circlips. Thorough cleaning (ultrasonic bath) is also absolutely essential to the weighing operation as otherwise the measurement result will be false.

1. A piston removed for repair is cleaned and identified. If it needs to be replaced, an X - piston with the identified weight tolerance + or - is ordered as a replacement part and installed.