OMC Evinrude Johnson Cap O Ring and Seal

An OMC Evinrude or Johnson "Cap-O-Ring & Seal" refers to a sealing component assembly used in various applications on OMC engines, often found in trim/tilt mechanisms or hydraulic systems. This assembly typically includes a metal or plastic cap, an O-ring, and a seal, working together to prevent fluid leakage. 

Elaboration:

Cap-O-Ring and Seal Assembly

This term describes a complete sealing component, usually an OEM part, designed to seal a specific area on the engine.

O-Ring

An O-ring is a round, circular mechanical gasket made of elastomer, used to create a seal by fitting into a groove and being compressed.

Seal:

Seals can be made from various materials like Viton or high-grade urethane, depending on the application's pressure and sealing requirements. 

Applications

These seals are common in trim and tilt mechanisms, hydraulic units, and other parts where preventing leakage is crucial.

Importance

The O-ring and seal prevent fluids from leaking, ensuring proper engine function and preventing damage.

OEM vs Aftermarket 

While OEM (Original Equipment Manufacturer) parts are factory-made, aftermarket parts are produced by other manufacturers and can be of varying quality. 

Manufacturer and Part Number

OMC parts, including seals, often have specific part numbers like 0390006, 0173594, or others that can help identify the correct replacement part.