Piston rings are engine components shaped like split rings that are mounted in special grooves on the pistons. They seal the gap between the piston and the cylinder wall. There are two types of piston rings:

• Compression rings (usually two per piston) – these seal the combustion chamber, preventing gas leakage during engine operation, which is crucial for maximum power and reliable engine performance.
• Oil control rings – these remove excess oil from the cylinder surface, preventing it from entering the combustion chamber and burning, which would create carbon deposits.

In addition, piston rings play a key role in heat transfer between the piston and the cylinder. Piston rings transfer heat from the piston to the cylinder walls, preventing the piston from overheating.

Signs of Piston Ring Failure

Regular inspections help to detect piston ring wear in time. Signs indicating the need for piston ring replacement may include:

• Increased fuel consumption;
• Increased oil consumption (blue smoke from the exhaust pipe, oil leaks through seals and gaskets);
• Reduced engine power due to decreased compression.

However, these symptoms are not always solely related to piston rings. To accurately diagnose and assess the condition of the cylinder-piston group (CPG), it is essential to measure compression using special devices called compression testers.

If the piston rings are worn out, they must be replaced. The lifespan of piston rings depends on the vehicle brand, operating conditions, and the quality of the components.