OMC Evinrude Johnson Gear Driven

OMC Evinrude and Johnson gear-driven outboards utilize a reduction gear system in their lower units to translate engine speed and torque into a usable propeller speed. This typically involves a pinion gear meshing with a larger gear, providing a gear ratio that optimizes the propeller for maximum performance. 

Here's a more detailed breakdown:

Pinion Gear:

A smaller gear that connects to the engine's crankshaft and rotates at engine speed.

Reduction Gear

A larger gear that meshes with the pinion gear and rotates at a slower speed, providing the desired propeller speed

Gear Ratio

The ratio between the number of teeth on the pinion and reduction gears determines the overall speed reduction

Propeller

The propeller, attached to the reduction gear, is rotated at the desired speed, which slower than the engine speed, but with more torque.

Model Years

OMC Gear-driven outboards were common in various models and year ranges. For example, some gear sets are specific to Evinrude and Johnson models from the 1960s and 1970s, including models with 55-60HP

OEM Parts 

OMC Evinrude and Johnson gear parts are often sold as OEM parts by suppliers

Maintenance

Proper lubrication and maintenance of the gear system are crucial for its longevity and reliability