O-Ring Kits

O-Ring Kits: The Small Rubber That Stops the Big Leak

An o-ring is the seal that lives in the groove between two mating parts, squeezing into place to keep oil, coolant, fuel or boost pressure where it belongs. When you crack open a blow-off valve, a pushrod cover, an oil pump housing or a coolant bypass, the original o-rings come out flattened, nicked or hardened. Reusing them is how a fresh reassembly turns into a slow weep two days later. That is what these o-ring kits are for: matched replacement seals for a specific assembly, so you reseal it once and move on.

Fit one whenever you have the housing apart. It is cheap insurance against a repeat teardown, and on pressurized systems it is the difference between holding boost or venting it past a tired seal.

What ThreePiece Stocks

This page carries 9 o-ring kits from 4 brands. The current in-stock price range runs from $28 to $38 — that is what is live now, not a standing promise. Turbosmart leads with five kits, followed by S&S Cycle with two, plus one each from Athena and Fleece Performance.

How to Choose

O-ring kits are not interchangeable — you buy the kit that matches your exact assembly. If you are resealing a Turbosmart Kompact valve, note whether it is the standard or the Shortie/VAG base version before ordering. For engine internals, the S&S kits are split by job: pushrod covers versus oil pump. The Athena kit is model-specific to the YZ 125, and the Fleece kit is a replacement seal set for their Cummins coolant bypass. Match the part number to the housing you have open rather than the price.

Fitment Coverage

Two of these kits list explicit vehicle fitment, covering Yamaha and Dodge — specifically the Yamaha YZ 125 and Dodge 2500/3500, across a 1994–2018 year range. The rest are keyed to a component (a valve or engine assembly) rather than a vehicle, so verify by part number.

What Else You Need

An o-ring rarely comes out alone. When you have the engine apart, look at Gasket Kits and Head Gaskets for the flat-sealing surfaces, and check Fittings and Adapters if you are reworking fluid lines at the same time. Browse the full Engine Components section for related sealing and service parts.

Fitment Help and Ordering

Not sure a kit matches your assembly? Call fitment help at 813-535-5801 or reach us through contact us. All orders ship free, and Affirm and Katapult financing is available at checkout.

O-Ring Kits: The Small Rubber That Stops the Big Leak

An o-ring is the seal that lives in the groove between two mating parts, squeezing into place to keep oil, coolant, fuel or boost pressure where it belongs. When you crack open a blow-off valve, a pushrod cover, an oil pump housing or a coolant bypass, the original o-rings come out flattened, nicked or hardened. Reusing them is how a fresh reassembly turns into a slow weep two days later. That is what these o-ring kits are for: matched replacement seals for a specific assembly, so you reseal it once and move on.

Fit one whenever you have the housing apart. It is cheap insurance against a repeat teardown, and on pressurized systems it is the difference between holding boost or venting it past a tired seal.

What ThreePiece Stocks

This page carries 9 o-ring kits from 4 brands. The current in-stock price range runs from $28 to $38 — that is what is live now, not a standing promise. Turbosmart leads with five kits, followed by S&S Cycle with two, plus one each from Athena and Fleece Performance.

How to Choose

O-ring kits are not interchangeable — you buy the kit that matches your exact assembly. If you are resealing a Turbosmart Kompact valve, note whether it is the standard or the Shortie/VAG base version before ordering. For engine internals, the S&S kits are split by job: pushrod covers versus oil pump. The Athena kit is model-specific to the YZ 125, and the Fleece kit is a replacement seal set for their Cummins coolant bypass. Match the part number to the housing you have open rather than the price.

Fitment Coverage

Two of these kits list explicit vehicle fitment, covering Yamaha and Dodge — specifically the Yamaha YZ 125 and Dodge 2500/3500, across a 1994–2018 year range. The rest are keyed to a component (a valve or engine assembly) rather than a vehicle, so verify by part number.

What Else You Need

An o-ring rarely comes out alone. When you have the engine apart, look at Gasket Kits and Head Gaskets for the flat-sealing surfaces, and check Fittings and Adapters if you are reworking fluid lines at the same time. Browse the full Engine Components section for related sealing and service parts.

Fitment Help and Ordering

Not sure a kit matches your assembly? Call fitment help at 813-535-5801 or reach us through contact us. All orders ship free, and Affirm and Katapult financing is available at checkout.