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Mercury Outboard Lower Unit Replacement – Fits 3.0L V6 / 2.6L I6 / 1.7L I4 (13 & 20 Splines) – 1.75 / 1.85 / 2.08 Ratios

Name: Mercury Outboard Lower Unit Replacement – Fits 3.0L V6 / 2.6L I6 / 1.7L I4 (13 &amp; 20 Splines) – 1.75 / 1.85 / 2.08 Ratios
SKU: ST-90-221
Availability: InStock
Rating: 4.15 (20 reviews)

Original price was: $2,070.15.Current price is: $1,869.00.

Rated 4.15 out of 5 based on 20 customer ratings

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SKU: ST-90-221 Categories: Mercury Force, Mercury Lower Unit, Standard

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Description
Additional information

Description

Mercury Outboard Lower Unit Replacement – Fits 3.0L V6 / 2.6L I6 / 1.7L I4 (13 & 20 Splines) – 1.75 / 1.85 / 2.08 Ratios – Aftermarket

The SE221 gearcases are designed to fit a variety of Mercury outboard engines, including 3.0 Liter V6 two-stroke, 2.6 Liter inline 6 four-stroke, and 1.7 Liter inline 4 four-stroke Verado models. These premium aftermarket lower units deliver reliability and a precise fit for specified models and serial ranges.

Engine Fitment Details

3.0 Liter V6 Two Stroke (13 spline)
Compatible with SEI 221-A20, 221-A25, and 221-A30 units
Replaces models from circa 2006 and later starting at serial #1B504989
Note: Not compatible with Torque Master, Torque Master 2, or Sport Master (“Fat Shaft” 19 spline)
2.6 Liter Inline 6 Four Stroke (20 spline)
Fits Verado 200–300 HP models with SE 221-A20F, 221-A25F, 221-A30F, 221-B20F, 221-B25F, and 221-B30F
For use with 4.8 Torpedo units; no replacement for 5.44 Torpedo
1.7 Liter Inline 4 Four Stroke (20 spline)
Designed for smaller Verado models, 135–200 HP, featuring superchargers
Available in standard or counter rotation versions
Not compatible with non-Verado inline 4 cylinder four strokes lacking superchargers

Specifications

Feature	Details
Engine Types	3.0L V6 2-Stroke, 2.6L I6 4-Stroke, 1.7L I4 4-Stroke
Gear Ratios	1.75:1, 1.85:1, 2.08:1
Shaft Splines	13 spline (3.0L V6), 20 spline (2.6L I6 & 1.7L I4)
Compatible Units	SE 221 series (various model numbers)
Exclusions	Torque Master, Torque Master 2, Sport Master
Rotation	Standard and Counter Rotation available

Note: Installation kit and anode kit are not included. Verify your exact model and serial number before ordering.

For fitment help or questions, contact us with your serial number.

Browse all Mercury Lower Units:
Mercury Lower Units

Official Mercury Marine specs:
Mercury Marine

Additional information

Weight	88 lbs
Dimensions	23 × 13 × 26 in
Splines/Ratio/Motor/Shaft Length	13/1.75/3.0L 2-Stroke/20" Shaft , 13/1.75/3.0L 2-Stroke/25" Shaft , 13/1.75/3.0L 2-Stroke/30" Shaft , 20/1.75/2.6L 4-Stroke/20" Shaft , 20/1.75/2.6L 4-Stroke/25" Shaft , 20/1.75/2.6L 4-Stroke/30" Shaft , 20/1.85/2.6L 4-Stroke/20" Shaft , 20/1.85/2.6L 4-Stroke/25" Shaft , 20/1.85/2.6L 4-Stroke/30" Shaft , 20/2.08/1.7L 4-Stroke/20" Shaft , 20/2.08/1.7L 4-Stroke/25" Shaft