90280-04M05 Yamaha Woodruff Key | Genuine OEM Yamaha Outboard Part

🔧 Product Description

Genuine Yamaha High-Horsepower Water Pump Woodruff Key - Part Number: 90280-04M05

A genuine Yamaha woodruff key used to drive the water-pump impeller on selected V4 and high-horsepower outboard lower units.

The key fits into the driveshaft keyway and engages the impeller hub, ensuring the impeller rotates at driveshaft speed.

⚙️ Key Features

• Genuine Yamaha OEM water-pump drive key

• Correct Yamaha part number 90280-04M05

• Precision-machined semicircular profile

• Included in Yamaha 6N6-series water-pump kits

• Sierra replacement key available

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• 90280-04M05 current OEM water-pump woodruff-key reference

OEM / Related Numbers:

• 90280-04M05

• 90280-04M05-00

• 6N6-W0078-02 related pump kit

• 6E5-44352-01 related impeller

Aftermarket / Verified Equivalents:

• Sierra: 18-3302

• Aftermarket Yamaha impeller drive key: 90280-04M05

🚤 Compatibility

Commonly used on:

• Yamaha V4 and high-horsepower lower-unit water pumps

• Impeller installations using the 6E5-series pump components

Typically suits:

• Engine models:

• Yamaha 100A two-stroke

• Yamaha 115B and 115C two-stroke

• Yamaha 130B two-stroke

• Yamaha 140B two-stroke

• Yamaha 115HP V4 production from approximately 1984 onward where specified

• Yamaha F115A early four-stroke

• Water-pump kit 6N6-W0078-02

• High-horsepower lower units using impeller 6E5-44352-01

• HP Range: Approximately 100HP - 140HP, with additional 6E5 pump-family applications

• Engine Type: Yamaha V4 two-stroke and early F115 four-stroke outboard

• Year Range: Lower-unit and pump-design controlled.

🔌 Function

The key mechanically couples the impeller to the driveshaft so the pump turns whenever the engine driveshaft rotates.

Common signs of failure:

• Impeller does not rotate

• Engine overheats immediately after pump service

• Key is missing during assembly

• Key is sheared or rolled over

• Impeller hub or driveshaft keyway is damaged

📦 Condition

• Genuine Yamaha part

• Brand new

• Supplied in original or equivalent packaging