221-3491 1.78 x 4.47 mm 90A FKM O-Ring
Cat® O-rings for hydraulic motor brake control valves ensure a leak-proof seal that maintains hydraulic oil integrity for precise brake control.
Description
The O-ring of the hydraulic motor brake control valve is a small, ring-shaped sealing component. It is designed with a round cross-section, with an inside diameter that matches the valve housing and an outside diameter that fits tightly against the sealing groove of the valve.
Attributes
- Resistant to aging and long-term degradation.
- Low-friction properties for efficient sealing.
- Resistant to extrusion and gap extrusion.
Applications
The O-ring in the hydraulic motor brake control valve forms a tight, watertight seal when placed in the valve, preventing hydraulic oil leakage and maintaining precise control of the hydraulic brake.
Specifications
| Compatible | Diester Lubricants; Halogenated Hydrocarbons (Above 100 Degrees C); Excellent Compression Set Resistant Material; Petroleum Fluids; Phosphate Ester Fluids; Silicone Oils; Certain Acids |
|---|---|
| Dash Size | 8 in |
| Material Hardness | 90A |
| Polymer | FKM (Fluorocarbon) |
| Color Note | Actual O-ring color may differ from the image. |
| Not Compatible | Amines; Brake Fluids; Engine Coolants; Fire-Resistant Fluids; Ketones; Steam; Water |
| Temperature | -40 – 175 °C (-40 – 350 °F) |
| Material Description | FKM rubber has a service temperature range of -40 to 150C and is resistant to air, fuel (including biodiesel), lubricants and engine oil. FKM rubber should not be used in applications requiring water or coolant resistance. |
| SAE AS568 Dash Size | -8 |
| Outside Diameter | 8.03 mm (0.32 in) |
| Coating | None |
| Application | High-pressure, high-temperature applications requiring resistance to air, fuel, lubricants and hydraulic oil; ORFS, STORS seals |
| Hardness | 90 Shore A |
| Seal Inside Diameter | 4.47 mm |
| Remarks | Dimensions and material descriptions are for reference only. |
| Cross-Section Diameter | 1.78 mm (0.07 in) |
| Inside Diameter | 4.47 mm (0.18 in) |
| Material | FKM (Fluorocarbon) |
Compatible Equipment
- Generator Sets: C4.4
- Wheel Excavators: M315, M320, M322D, M313D, M315GC, M315D, M320D2, M317D2, M315D2
- Compactors: CP56B, CS68B, CS78B, CS74B, CS56B, CB-44B, CB-66B, CB-64B, CB16, CS12, CB10, CB15, CB13
- Engines: C32
- Excavators: M325D L MH
- Wheel Loaders: RM400, M314, RM500B
Additional information
| Machine Model | C32, C4.4, CB-44B, CB-64B, CB-66B, CB10, CB13, CB15, CB16, CP56B, CS12, CS56B, CS68B, CS74B, CS78B, M313D, M314, M315, M315D, M315D2, M315GC, M317D2, M320, M320D2, M322D, M325D L MH, RM400, RM500B |
|---|---|
| Equipment Type | Excavators, Wheel Excavators, Wheel Loaders, Compactors, Engines, Generator Sets |
| Part Source | Genuine OEM |








