L57-SW945 Yamaha Starter Solenoid | Genuine Used Part

🔧 Product Description

ARCO Yamaha / Mercury Starter Solenoid - Part Number: SW945

A used ARCO Marine 12-volt starter solenoid for selected Yamaha two-stroke and four-stroke outboards and compatible Mercury four-stroke engines.

The supplied L57 marking is a component or production marking. SW945 is an aftermarket ARCO part rather than a genuine Yamaha component. It replaces several Yamaha and Mercury starter-solenoid numbers and cross-references with Sierra 18-5821.

⚙️ Key Features

• ARCO Marine aftermarket starter solenoid

• Correct ARCO part number SW945

• 12-volt electric-start relay

• Replaces Yamaha and Mercury OEM solenoids

• Sierra 18-5821 cross-reference

🔄 Supersession & Cross Reference

OEM Supersession Chain:

• Yamaha 6G1-8194A-10 later OEM reference

• Yamaha 6G1-81941-10 related OEM reference

• Yamaha 6G1-81940-00 earlier OEM reference

• Mercury 825096T01 later Mercury reference

• Mercury 89-825096T / 89-825096 earlier Mercury references

OEM / Related Numbers:

• ARCO: SW945

• Component Marking: L57

• Yamaha: 6G1-8194A-10

• Yamaha: 6G1-81941-10

• Yamaha: 6G1-81940-00

• Mercury: 825096T01

• Mercury: 89-825096T

• Mercury: 89-825096

Aftermarket / Verified Equivalents:

• Sierra: 18-5821

• ARCO Marine: SW945

🚤 Compatibility

Commonly used on:

• Yamaha two-stroke electric-start systems

• Yamaha four-stroke electric-start systems

• Mercury Yamaha-built four-stroke outboards using 825096-series solenoids

Typically suits:

• Engine families:

• Yamaha 20HP and 25HP electric-start models

• Yamaha 30HP and 40HP electric-start models

• Yamaha 50HP and 60HP electric-start models

• Yamaha 75HP, 80HP, 85HP and 90HP models using the 6G1 solenoid

• Yamaha 115HP through 300HP models where 6G1-8194A-10 is specified

• Mercury four-stroke models using 825096T01

• Electrical System: 12-volt electric start

• Engine Type: Yamaha two-stroke and four-stroke outboard; compatible Mercury four-stroke

• Fitment Requirement: Match the OEM number, terminal arrangement and mounting centres before installation

🔌 Function

The solenoid closes the high-current starter circuit when the ignition switch supplies voltage to the control terminal.

Common signs of failure:

• Starter does not crank

• Solenoid clicks without supplying starter power

• Intermittent electric starting

• Burnt or loose electrical terminals

• Solenoid remains engaged after starting

📦 Condition

• Used ARCO aftermarket part

• Removed from running engine where applicable

• In good working condition unless otherwise stated