Product Overview
These Captain O-Ring Viton FKM O-rings are designed for replacing worn or damaged O-rings in 1/4" quick coupler fittings commonly found on pressure washer wands and hoses. Made from high-temperature Viton FKM rubber, they offer excellent resistance to heat and chemicals, ensuring a reliable seal for your pressure washing equipment.
Key Features
- Material: Viton FKM Rubber, compatible with many chemicals and cleaners.
- Dimensions: 3/8" Inside Diameter x 0.100" Thick. These are specifically designed for 1/4" Quick Connect fittings.
- Temperature Resistance: Compatible with temperatures up to 400°F (204°C).
- Durability: Features tear and abrasion resistance for long-lasting performance.
- Quantity: Each package contains ten (10) O-rings.
Installation Guide
Replacing O-rings in your pressure washer quick coupler fittings is a straightforward process. Follow these steps to ensure a proper seal and prevent leaks.
Step 1: Identify the Correct O-Ring Size
These O-rings are specifically designed for 1/4" Quick Connect fittings. While the fitting is 1/4", the O-ring itself measures 3/8" Inside Diameter and 0.100" Thick. It is crucial to verify your fitting size before installation. If your fitting is 3/8", you will need O-rings with a 1/2" ID.

Image: Diagram illustrating the dimensions of the O-ring (3/8" ID, 0.100" Thick) and clarifying its use with 1/4" Quick Connect fittings.
Step 2: Prepare the Fitting
Disconnect the pressure washer from its power source and water supply. Relieve any residual pressure in the system. Carefully disassemble the quick coupler or threaded fitting where the O-ring needs replacement.

Image: Examples of 1/4" Female Quick Connect and M22 Threaded fittings where these O-rings are used. Red arrows indicate the O-ring location.
Step 3: Remove Old O-Ring
Use a small pick or a thin, non-abrasive tool to carefully remove the old, worn, or damaged O-ring from its groove. Inspect the groove for any debris or damage and clean it thoroughly.
Step 4: Install New O-Ring
Lightly lubricate the new Viton FKM O-ring with silicone grease or a small amount of water to aid in installation and prevent pinching. Carefully place the new O-ring into the clean groove, ensuring it sits flat and is not twisted.
Step 5: Reassemble and Test
Reassemble the fitting, ensuring all connections are secure. Reconnect the pressure washer to the water supply and power. Turn on the water and check for leaks before operating the pressure washer at full pressure.
Video Guide: Pressure Washer Quick Connect O-Rings Overview
Video: An overview of Captain O-Ring's pressure washer quick connect O-rings, demonstrating their application and benefits.
Maintenance
Regularly inspect your pressure washer O-rings for signs of wear, cracking, or flattening. Replace them promptly to maintain optimal performance and prevent leaks. Store spare O-rings in a cool, dry place away from direct sunlight and harsh chemicals to prolong their lifespan.
Troubleshooting
Issue: Leaks after O-ring replacement
- Incorrect Size: Ensure you have installed the correct O-ring size for your fitting. These O-rings are for 1/4" Quick Connect fittings, which use a 3/8" ID O-ring. A common mistake is using an O-ring that is too large or too small for the specific fitting, leading to leaks or difficulty in connection.
- Improper Seating: Verify that the O-ring is seated correctly in its groove and is not twisted or pinched during reassembly.
- Damaged Fitting: Inspect the fitting itself for any cracks, burrs, or damage that might prevent a proper seal, even with a new O-ring.
- Insufficient Lubrication: A dry O-ring can be damaged during installation or fail to seal properly. Ensure light lubrication.
Specifications
| Property | Value |
|---|---|
| Material | High Temp Viton Rubber |
| Nominal Inside Diameter | 0.38 Inches |
| Item Diameter | 0.38 Inches |
| Color | Black |
| Nominal Outside Diameter | 0.25 Inches |
| Temperature Range | Up to 400°F |
| Unit Count | 10 Count |
| Manufacturer | Captain O-Ring LLC |
| Model Number | S9-HRAM-U4EG |
Warranty and Support
These O-rings are manufactured and warrantied by Captain O-Ring LLC. For any questions, support, or warranty claims, please refer to the contact information provided on the product packaging or visit the official Captain O-Ring website.





