M7x137 Viton O-Ring 75A Durometer, 137mm ID - Reliable Seal

In this review the M7x137 Viton O-Ring is judged as a practical, purpose-driven seal for mechanical and hydraulic applications where chemical and heat resistance matter. It is best for technicians, hobbyists, and equipment maintainers who need a dependable replacement O-ring in a known size; the single biggest reason to buy is the material choice - Viton fluorocarbon - which offers broad chemical compatibility and high temperature tolerance that many standard elastomers cannot match.

Key Features

• Material: Made of Viton (fluorocarbon elastomer) so it resists fuels, oils and many chemicals that degrade other rubbers.
• Hardness: The 75A durometer provides a firm but flexible seal that balances compressibility and wear resistance for dynamic and static joints.
• Temperature range: Rated for use across a wide range of temperatures, allowing the O-ring to perform from low temperatures up to high-heat engine or industrial environments.
• Cross-section: The round cross-section forms an effective seal between cylindrical overlapping surfaces for shafts, barrels, or housings.
• Size consistency: The 137 mm inner diameter and 151 mm outer diameter with 7 mm width mean this pack fits applications that require those metric dimensions without modification.
• Pack quantity: Sold as a pack of 5, which provides spare parts for routine maintenance or multiple installations.

Who It's For

This O-ring is aimed at users who need a chemically resistant seal for industrial, automotive, or small-engine tasks, including replacing seals on threaded barrels and carburetor seats where fit and seal quality matter. It appeals to maintenance techs and DIY mechanics who value a proven material like Viton for reliability under fuel and oil exposure.

It is less appropriate for applications exposed to strong bases, ammonia gas, or super-heated steam, where compatibility issues are known. Also consider alternative elastomers if extreme low-temperature flexibility below -15 degrees F is a requirement.

Pros & Cons

Pros

• Excellent chemical and fuel resistance provided by the Viton compound for long-term sealing in contaminated environments.
• Good balance of firmness and compliance with the 75A durometer, helping maintain a reliable seal under pressure.
• Size and fit praised by customers for specific threaded barrels and carburetor seat seals, indicating dependable real-world performance.
• Pack of 5 gives value and spares for maintenance cycles.

Cons

• Not compatible with certain substances such as ammonia gas, strong alkalis, and some organic acids, so users must confirm chemical compatibility for their system.
• The temperature range noted in the description contains slightly different upper limits in different lines, so verify the required maximum for your application.

Specifications

Material	Viton (fluorocarbon elastomer)
Durometer	75A
Cross-section	Round
Inner diameter (ID)	137 mm
Outer diameter (OD)	151 mm
Width	7 mm
Temperature range	-15 degrees F (-26 degrees C) to 400-450 degrees F (205-232 degrees C)

Our Verdict

The M7x137 Viton O-Ring is a solid, cost-effective choice for anyone needing a reliable metric seal that resists fuels and many chemicals; its Viton construction and 75A hardness deliver dependable performance for threaded barrels, carburetor seats, and similar applications, and the 5-pack makes it good value for maintenance or repairs.

Frequently Asked Questions

Is this O-ring compatible with gasoline and hydraulic oils?
Yes, Viton is compatible with non-flammable hydraulic fuels, many oils and aromatic and aliphatic hydrocarbons, making it suitable for those fluids.

What temperatures can this O-ring handle?
The listed operational range covers low temperatures to high heat environments, roughly -15 degrees F (-26 degrees C) up to about 400-450 degrees F (205-232 degrees C); confirm the exact upper limit needed for your system.

How many O-rings are included?
This product is sold as a pack of 5, providing spares for multiple installations or future maintenance.