Mercury 221 (Replaces Some 3.0L V6, 2.6L I6 AND 1.7L I4)

SKU: ST-90-221
The 221 gearcases fit three different types of engines. They are as follows: 3.0 Liter – V6 – Two Stroke

Mercury 205

SKU: ST-90-205
Mercury 205 Outboard Lower Unit SUPERIOR QUALITY: Mercury 205 outboard lower unit offers the best products at affordable prices. We

Mercury 206

SKU: ST-90-206
The SE 206 gear case replaces most Mercury 2.0, 2.4 and 2.5 liter gear cases with 4-3/4 Bullet Diameter

Mercury 216

SKU: ST-90-216
Mercury 216 sei lower unit HIGH QUALITY: Mercury 216 lower unit has superior stability, durability, and performance because it is

Mercury Counter Rotation 218

SKU: ST-90-218
Mercury Counter Rotation 218 Lower Unit SUITABLE FOR: Mercury counter rotation 218 unit is Only suitable for Mercury 3.0 L

The Importance of the Mercury Lower Unit

The lower unit of a Mercury outboard engine serves as the powerhouse of propulsion, translating the engine's power into forward or reverse motion. It houses a complex arrangement of gears, bearings, and seals meticulously designed to withstand the rigors of marine environments.

Key Components

  1. Gearbox: At the heart of the lower unit lies the gearbox, where the engine's power is transferred from the driveshaft to the propeller shaft. Mercury's precision-engineered gears ensure smooth and efficient power transmission, enhancing overall performance on the water.

  2. Driveshaft: Connected to the engine's crankshaft, the driveshaft delivers rotational power to the gearbox, initiating the propulsion process. Mercury's driveshafts are engineered for optimal strength and durability, capable of withstanding high torque loads and prolonged use.

  3. Propeller Shaft: Extending from the gearbox to the propeller hub, the propeller shaft transfers rotational motion to the propeller, generating thrust to propel the boat forward. Mercury's propeller shafts are crafted from corrosion-resistant materials, ensuring long-lasting performance in harsh marine conditions.

Durability and Reliability

Mercury lower units are renowned for their durability and reliability, built to endure the demanding conditions of marine environments. Rigorous quality control measures and advanced manufacturing techniques ensure each unit meets Mercury's stringent standards for performance and longevity.

Maintenance and Care

Proper maintenance is essential to maximize the lifespan of a Mercury lower unit. Regular inspections, lubrication, and fluid changes are critical to prevent wear and maintain optimal performance. Additionally, prompt repairs of any leaks or damage can help avoid costly issues down the line.


Mercury Force Lower Unit

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