Mr O-Ring 228 Viton O-Ring 90A Durometer Pack of 25 - High Temp Seal

In this review the Mr O-Ring 228 Viton O-Ring pack of 25 is evaluated for mechanical and fluid sealing tasks where heat, fuels, and solvents are present. The bottom line: this kit is for technicians and hobbyists who need a reliable, heat-resistant seal in a standard AS568 size. Its 90A durometer Viton (FKM) composition and an operating range that stretches to 232C (450F) make it a solid choice when long-term exposure to petroleum products, biodiesel blends, or hot environments is the primary concern.

Key Features

• Material: Viton FKM provides exceptional resistance to high temperature, ozone, weather and many solvents, reducing seal failures in hostile environments.
• Hardness: The 90A durometer offers a balance of firmness and sealing elasticity, suitable for static and many dynamic sealing applications.
• Size accuracy: Nominal 2-1/4 in ID and 2-1/2 in OD with actual dimensions very close to spec, making replacements straightforward for AS568 size users.
• Temperature range: Rated from -26C (-15F) to 232C (450F), allowing use across a wide span of ambient and operating temperatures.
• Compatibility: Performs well with petroleum fuels, methanol or ethanol blends, diesel and biodiesel, mineral and silicone oils and greases, and many chemicals encountered in industrial service.
• Pack size: Supplied as a pack of 25, which reduces downtime by keeping multiple spares on hand for maintenance tasks.

Who It's For

This product suits maintenance technicians, mechanics, and engineers who work on fuel systems, pumps, hydraulic fixtures or equipment exposed to high temperatures or aggressive fluids. The pack format is helpful for shops that service multiple units or for field technicians who need consistent, on-the-shelf spare parts.

Users who need softer elastomers for low-pressure dynamic seals, food-grade approval, or extreme low-temperature flexibility should consider alternative compounds. Also, if custom cross-sections or nonstandard sizes are required, a single-size pack may not meet those needs.

Pros & Cons

Pros

• Excellent chemical and high-temperature resistance from the Viton FKM compound for long-term reliability.
• 90A durometer provides a dependable seal while remaining resilient enough for many static and semi-dynamic applications.
• Close actual-to-nominal dimensions and adherence to AS568 sizing simplify replacements and inventory management.
• Pack of 25 supplies multiple repairs and reduces interruption for routine maintenance.

Cons

• Higher hardness limits suitability for very low-temperature flexibility or delicate dynamic shafts where softer elastomers are preferred.
• Not intended for applications requiring food-grade or medical approvals.

Specifications

Material	Viton (FKM)
Durometer	90A
Nominal Dimensions	2-1/4 in ID, 2-1/2 in OD, 1/8 in CS
Actual Dimensions	2.234 in ID, 2.512 in OD, 0.139 in CS
Metric Dimensions	56.74 mm ID, 63.80 mm OD, 3.53 mm CS
Temperature Range	-26C (-15F) to 232C (450F)
Pack Quantity	25

Our Verdict

The Mr O-Ring 228 Viton O-Ring pack is a practical, cost-effective choice for professionals needing durable, heat- and chemical-resistant seals in a common AS568 size. It delivers reliable performance for fuel, oil and high-temperature applications and provides good inventory value with 25 pieces per pack; those needing softer compounds or regulatory approvals should look elsewhere.

Frequently Asked Questions

Are these o-rings suitable for fuel systems?
Yes. The Viton FKM material resists petroleum fuels, ethanol and methanol blends and biodiesel, making them suitable for many fuel system sealing tasks.

Do the sizes match standard AS568 dimensions?
Yes. The o-rings correspond to the AS568 228 size with nominal and actual dimensions close to the standard listed values.

Can they be used in high-temperature applications?
Yes. The rated temperature range up to 232C (450F) supports use in high-temperature environments.