Piston Installation

1. Ensure that connecting rod tolerances are within specifications.
2. Clean piston, removing any heavy oil discoloration on piston crown and in ring grooves, being careful not to damage surfaces. An uneven blue mark or one sided traces of carbon deposits on piston body at a right angle to piston axis may be caused by a bent connecting rod.
3. Ensure piston rings are in good condition and that ring gaps and groove clearances are within specifications.
4. Measure piston. Dimensional groups are marked on crowns of pistons.
5. Using tool VW121b or equivalent, install piston rings with TOP mark facing upward.
6. Install piston pin circlip on one side of piston, then insert piston pin from opposite side of piston.
7. Install piston on connecting rod so that larger valve pocket machined on piston faces intake side.
8. Install second circlip so that opening in circlip faces either piston crown or in opposite direction.
9. Install cylinders.