6E5-WS857-00 Yamaha Control Unit Kit | Genuine OEM Yamaha Outboard Part

🔧 Product Description

Genuine Yamaha Oil Injection Control Unit Kit - Part Number: 6E5-WS857-00

A genuine Yamaha electronic control unit for selected oil-injected V4 and V6 two-stroke outboards.

The controller receives signals from the engine-mounted and remote oil-tank level sensors. It operates the remote-tank transfer pump, controls oil-warning functions and helps maintain the correct oil level in the engine reservoir.

⚙️ Key Features

• Genuine Yamaha OEM oil-injection control unit
• Correct current Yamaha part number 6E5-WS857-00
• Controls automatic remote-to-engine oil transfer
• Interfaces with oil-level sensors, alarms and transfer-pump wiring
• Supersedes earlier 6E5-85740 control modules

🚤 Compatibility

Commonly used on

• Yamaha Precision Blend oil-injection systems
• Remote oil-tank transfer-pump and engine oil-reservoir control circuits

Typically suits

• Engine models:
• Yamaha 115HP oil-injected V4 two-stroke
• Yamaha 115CETO
• Yamaha 130HP oil-injected V4 two-stroke
• Yamaha 140CETO and L140CET
• Yamaha 150HP oil-injected V6 two-stroke
• Yamaha 175HP oil-injected V6 two-stroke
• Yamaha 200HP oil-injected V6 two-stroke
• Yamaha ProV and Excel oil-injected V6 engines
• Yamaha 115 / 130 / 140 models using the 1988-and-later oil control system
• Selected Yamaha 225HP oil-injected systems where the diagram specifies 6E5-WS857-00
• HP Range: Approximately 115HP - 225HP
• Engine Type: Yamaha V4 and V6 oil-injected two-stroke outboard
• Year Range: Approximately 1988-2003, dependent on oil-tank wiring and control system

🔌 Function

The control unit commands the remote oil-transfer pump when the engine reservoir level falls and activates warning or protection functions when an oil-level fault is detected.

⚠️ Common Signs of Failure

• Remote oil tank does not transfer oil automatically
• Engine oil reservoir level falls despite oil in the remote tank
• Oil warning remains active with correct tank levels
• Emergency transfer switch works but automatic transfer does not
• No voltage command reaches the remote oil pump
• Intermittent oil alarm or reduced-power protection occurs

🔄 Supersession & Cross Reference

OEM Supersession Chain

• 6E5-WS857-00 → Supersedes 6E5-85740-02
• 6E5-85740-02 → Supersedes 6E5-85740-01
• 6E5-85740-01 earlier OEM oil-control module reference

OEM / Related Numbers

• 6E5-WS857-00
• 6E5-WS857-00-00
• 6E5-85740-02
• 6E5-85740-01
• 6E5-WS857-10 related later control-unit assembly
• Oil tank controller
• Precision Blend oil control module

Aftermarket / Verified Equivalents

• No aftermarket equivalent

📦 Condition

• Genuine Yamaha part
• Brand new
• Supplied in original or equivalent packaging