STIHL Piston Rings

Piston rings are small but essential when it comes to engine components. Fitted around the piston, they help maintain cylinder compression while lubricating between the piston and cylinder wall.

As rings wear, the engine loses compression, which affects performance. Replacing worn piston rings is therefore a simple fix, but an important part of an engine repair or rebuild.

Replacement Piston Rings & Ring Sets

Our range includes individual piston rings and piston ring sets for a wide variety of STIHL petrol-powered equipment. Current applications include chainsaws, disc cutters, brushcutters, blowers and hedge trimmers, with rings available in different diameters and thicknesses.

For example, our range of genuine STIHL aftermarket piston rings includes a 50mm x 1.2mm piston ring set for the STIHL TS410 and TS420, as well as individual genuine STIHL rings for specific applications.

Some replacement rings are supplied as sets, while others are sold individually, so check the product description carefully before ordering.

What Do Piston Rings Do?

Piston rings perform several important functions inside a petrol engine. They help to:

• Maintain compression between the piston and cylinder

• Limit the movement of combustion gases past the piston

• Help regulate the oil film on the cylinder wall

• Transfer heat from the piston towards the cylinder

Signs of Worn Piston Rings

Piston-ring wear can contribute to symptoms such as:

• Reduced engine power

• Loss of compression

• Difficulty starting

• Increased exhaust smoke

• Increased oil consumption on applicable engines

• Poor overall engine performance

These symptoms can also have other causes, however, so it is important to diagnose the engine before replacing the rings.

Choosing the Correct Piston Ring

Piston rings are highly specific, so although two may look identical, they can have different diameters and thicknesses and may be designed for completely different engines.

The GHS range includes rings measuring 34mm, 40mm, 47mm, 49mm, 50mm and more, with thicknesses of 1.2mm and 1.5mm, for example. To figure out which you need, check your STIHL machine model, piston diameter, ring thickness, original part number and whether you require a single ring or a complete ring set.

If you're replacing rings as part of an engine rebuild, it's also important to assess the condition of the piston and cylinder rather than assuming the rings are the only worn components.

You can browse our STIHL piston assemblies if you require a piston and associated components, or use our STIHL Parts Diagrams to help identify the correct engine component. If you're still unsure which piston ring you need, our STIHL Part Identification Service can help.