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Mercury Outboard Lower Unit Replacement – Fits 3L – 1.62 & 1.75 Ratios – Counter Rotation – Aftermarket

Name: Mercury Outboard Lower Unit Replacement – Fits 3L – 1.62 &amp; 1.75 Ratios - Counter Rotation - Aftermarket
SKU: ST-90-218
Availability: InStock
Rating: 3.79 (14 reviews)

Original price was: $1,548.45.Current price is: $1,395.00.

Rated 3.79 out of 5 based on 14 customer ratings

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SKU: ST-90-218 Categories: Counter Rotation, Engine & Parts, Mercury Force, Mercury Lower Unit

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Description
Additional information

Description

Mercury Outboard Lower Unit Replacement – Fits 3L – 1.62 & 1.75 Ratios – Counter Rotation – Aftermarket

The SE218 counter rotation lower unit is engineered to replace most Mercury 3.0L outboards (serial number 1B504989 and below). Perfect for marine enthusiasts demanding long-lasting reliability, this robust, aftermarket assembly is available with 25″ or 30″ 13-spline one-piece drive shafts and supports both 1.62:1 and 1.75:1 gear ratios for optimal performance in counter-rotation setups.

Key Features

Designed for Mercury 3.0L V6 outboards (SN 1B504989 and below)
Supports counter rotation for twin-engine configurations
Available in 1.62:1 and 1.75:1 gear ratios
Shaft options: 25″ or 30″ (13 spline) one-piece drive shaft
Stub shaft version available for engines with 8-spline drive
Not compatible with Torque Master, Torque Master 2, or Sport Master

Specifications Table

Feature	Details
Fitment	Mercury 3.0L Outboards (SN 1B504989 & below)
Gear Ratios	1.62:1, 1.75:1
Shaft Options	25″ (45-823901A 1), 30″ (45-824115A 1, NLA*)
Spline Info	13-spline standard, stub shaft for 8-spline
Water Tube Coupling	Included for SN OG438000+, otherwise reuse or order 96-116-12K
Additional Notes	Upgrade from 13-spline two-piece with the correct one-piece shaft
Rotation Type	Counter rotation
Exclusions	Does not replace Torque Master, Torque Master 2, Sport Master

$N L A - N o L o n g er A v ai l ab l e f ro m OE f or 30”; so u rce u se d orre p ai ryo u ro l dd r i v e f or t hi so pt i o n$

Compatibility Notes

For 8-spline setups, purchase the stub shaft unit and an OE upper driveshaft.
If unit serial is lower than OG438000, use your old water coupling or purchase SEI #96-116-12K.
13-spline two-piece shaft users: upgrade to the matching one-piece shaft as listed.

For expert fitment guidance, please call 888 868 7880 with your engine serial number.

Browse more lower unit options:

All Mercury Lower Units

Official resources:
Mercury Marine

Additional information

Weight	92 lbs
Dimensions	23 × 13 × 31 in
Splines/Ratio/Motor/Shaft Length	13/1.62/3.0L/25″Shaft , 13/1.62/3.0L/Stub Shaft , 13/1.75/3.0L/25″Shaft , 13/1.75/3.0L/30″Shaft , 13/1.75/3.0L/Stub Shaft