SEI Marine Products

Replaces the gear case on most Yamaha V-4 2-Stroke with 25 inch drive shaft.
The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.

SE405 Anode Kit

Replaces most Yamaha 90 Degree V6 2-Stroke and some inline 4 cylinder 4-Stroke engines

The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.

Replaces the gear case on most Yamaha 90 Degree V6 2.6 Liter
2-Stroke Engines with 20 inch drive shaft.


The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.

Replaces gear case on most Yamaha 90 Degree V6 2.6 Liter 2-Stroke Engines.
The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.

Replaces most Yamaha 90 Degree V6 2.6 Liter 2-Stroke engines
The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.

Replaces most Yamaha 4-Stroke 150HP engines with a 20"" drive shaft.
The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore. color may vary depending on product availability at time of order.

Replaces most Yamaha 4-Stroke 150HP engines with 25" drive shaft. The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.

Anode for SE416

Replaces most Yamaha 90 Degree V6 2-Stroke engines with a 1.86 Gear Ratio.

For Counter Rotation applications only (do not use for Standard Rotation).

The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order

This SE418 (90-418-B25F) is a Counter Rotation Gear Case. This is a Counter Rotation Gear Case replacement for the Yamaha FOUR Stroke 150HP Engine with a 1.86 Gear Ratio and a 25" Drive Shaft. The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.
Fits Yamaha SE418-2-0 Counter Rotation 4 Stroke.

This SE418 (90-418-A25) is a Counter Rotation Gear Case. This is a Counter Rotation Gear Case replacement for the Yamaha 2 Stroke V6 2.6 Liter Engine with a 1.86 Gear Ratio a 25" Drive Shaft and a Counter (Left Hand)Rotation. The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order
Fits-Yamaha-SE418-1-86-Counter-64H-45300-22-8D

Replaces most Yamaha 76 Degree V6
The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order

Not designed for Yamaha F250 four stroke 250 HP motors

The SE421(90-421-A20) comes with the 1.81:1 Gear Ratio, and a 20" Drive Shaft. This is a standard right hand rotation gear case. It replaces gear cases on Yamaha 2 Stroke V6 3.1 and 3.2 Engines with Right Hand Rotation. The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.
SE-421-1-81-20 Driveshaft-66K-45300-12-NA

This SE421 (90-421-A25) Replaces the Gear Case on Yamaha V6 2 Stroke 3.1 and 3.2 Liter Engines with Standard Right Hand Rotation. 1.81:1 Gear Ratio 25 Inch Drive Shaft. The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.
SE-421-1-81-25 Driveshaft 60V-45300-20-8D

SE421 1.81:1 Ratio / 30"" Shaft / 2 Stroke V6 / RH Rotation The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order.
SE-421-1-81-30 Driveshaft 60V-45300-30-8D

The SE421 (90-421-B25F) Replaces Gear Case on
Yamaha Four Stroke V6 200HP - 225HP Engines
with 2:1 Gear Ratio, 25 Inch Drive Shaft and
Standard Right Hand Rotation The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order
SE-421-2-0-69J-45300-21-8D

The SE421 (90-421-B30F) Replaces the Gear Case on Yamaha
Four Stroke V6 200HP - 225HP Engines with
30 Inch Drive Shaft and Standard Right Hand Rotation The paint color for all lower units is transitioning to black as inventory becomes depleted. Therefore, color may vary depending on product availability at time of order
SE-421-2-0-69J-45300-31-8D

Anode kit for SE421

SE421 Installation Kit

SE421 Installation Kit Fits OMC Needle Bearing