Replacement Yamaha Lower Units

We offer replacement Yamaha lower units for 75–300 HP applications, available in 20-, 25-, and 30-inch shafts with all gear ratios to match your existing unit. Every unit is backed by a 3-year fault-free warranty.

Yamaha Outboard Lower Unit | 2.3 | 25" | 4 - Stroke | 90 - 404 - B25F - MarinePartsCo - 90 - 404 - B25F
Yamaha Replacement Lower Unit | 2.0 | 25" | 2 Stroke | 90-404-A25
SEI Marine MPN : 90-404-A25
$1,195.00 USD -100%
$1,195.00 USD
Yamaha SE421 Anode Kit - MarinePartsCo - 90 - 421 - 05k - Anode
Yamaha replacement SE421 Anode Kit
SEI Marine MPN : 90-421-05k-Anode
$27.50 USD -100%
$27.50 USD
Yamaha SE421 Installation Kit - MarinePartsCo - 90 - 421 - 03K
Yamaha replacement SE421 Installation Kit
SEI Marine MPN : 90-421-03K
$71.50 USD -100%
$71.50 USD
Yamaha SE416 Outboard Lower Unit Anode Kit - MarinePartsCo - 90 - 416 - 05k
Yamaha replacement SE416 Outboard Lower Unit Anode Kit
SEI Marine MPN : 90-416-05k
$27.50 USD -100%
$27.50 USD
Yamaha SE421 Anode Kit - MarinePartsCo - 90 - 421 - 05k - Anode
Yamaha replacement SE405 Anode Kit
SEI Marine MPN : 90-405-05K
$27.50 USD -100%
$27.50 USD
Skeg Guard for SE404 Lower Units - MarinePartsCo - 87 - 032 - K
Skeg Guard for SE404 Lower Units
SEI Marine MPN : 87-032-K
$89.00 USD -100%
$89.00 USD
Skeg Guard for SE405 Lower Units - MarinePartsCo - 87 - 029 - K
Skeg Guard for SE405 Lower Units
SEI Marine MPN : 87-029-K
$89.00 USD -100%
$89.00 USD
Skeg Guard for SEI 416/418/421/422/428/429 Lower Units - MarinePartsCo - 87 - 030 - K
Skeg Guard for SEI 416/418/421/422/428/429 Lower Units
SEI Marine MPN : 87-030-K
$89.00 USD -100%
$89.00 USD
Yamaha SE421 Installation Kit - MarinePartsCo - 90 - 421 - 03K
Yamaha replacement SE405 / SE416 Installation Kit
SEI Marine MPN : 90-416-03k
$66.00 USD -100%
$66.00 USD
Yamaha SE421 Anode Kit - MarinePartsCo - 90 - 421 - 05k - Anode
Yamaha Replacement Lower Unit Anode Kit
SEI Marine MPN : 90-421-05K
$27.50 USD -100%
$27.50 USD
Yamaha Outboard Lower Unit | 30" | 4 Stroke | 90 - 430 - B30F - MarinePartsCo - 90 - 430 - B30F
Yamaha Replacement Lower Unit | 30" | 4 Stroke | 90-430-B30F
SEI Marine MPN : 90-430-B30F
$1,865.00 USD -100%
$1,865.00 USD
Yamaha Outboard Lower Unit | 25" | 4 Stroke | 90 - 430 - B25F - MarinePartsCo - 90 - 430 - B25F
Yamaha Replacement Lower Unit | 25" | 4 Stroke | 90-430-B25F
SEI Marine MPN : 90-430-B25F
$1,865.00 USD -100%
$1,865.00 USD

Why MarinePartsCo?

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Premium Quality

Built to OEM specifications, we only sell the highest quality replacement parts

Expert Support

Fitment first guidance, we want to make sure the part is correct before it ships

Fast Shipping

Quick delivery to get you back on the water as soon as possible.