Genuine Audi A3 Piston Ring

Audi A3 Piston Ring Parts and Q&A

• Piston Rings
  03L-198-151-C
  Q: How should the ring end gaps be checked and corrected before fitting new piston rings on Audi A3?

  A:

  The end gaps should be measured by placing the Piston rings end gaps by placing piston/connecting rod assembly and the new piston ring sets in a matched position with the previous piston and cylinder before installing new piston rings. Install the top ring into the first cylinder and force it down the bore with the top of the piston to keep the ring square with the walls of the cylinder with the bottom of the cylinder bore, which is the lower limit of the ring travel, the top and second compression rings being different. Measure the end gap by means of feeler blades and check the results with the specifications. In case of a small gap, the gap should be increased to avoid the ring ends to touch with each other in the process of engine operation which can cause serious damages, instead, they should be installed with new piston rings that have the right end gap. Finally as an extreme measure, lightly file the ends of the rings with a fine file but easily they are cut and broken so care must be taken. The end gap should not be excessively large with new piston rings but in the event that they are excessively so, make sure that the appropriate rings to the engine and cylinder bore size are in place. Check the procedure of the first cylinder again but with rings in the second cylinder and so on but it is vital to have rings, pistons, and cylinders matched. When the gaps at the end of the rings are checked and repaired where necessary the rings may be attached to the pistons by the same process as the removal process, commencing with the bottom (oil control) ring and then moving up. Two or three section oil control ring can also be fitted in which case the two section ring will have first to install the wire expander and then fit the ring. Install the rings in the correct orientation being the top surface is usually identified, and balance the gaps between the piston rings by 120 degrees. Different manufacturers may give different instructions to follow with the new piston ring sets and do not confuse between the top and second compression rings because they have different cross-sections.