Thermostat for Yamaha Outboard 2-Stroke Engines | Replaces 688-12411-10 / 6H3-12411-11 / 6E5-12411-02 | 60°C Rated

Thermostat for Yamaha Outboard 40 50 HP 2 Stroke 6E5-12411 - 4Boats

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£19.94

Tax included.

Yamaha Thermostat 6E5-12411

Name: Thermostat for Yamaha Outboard 2-Stroke Engines | Replaces 688-12411-10 / 6H3-12411-11 / 6E5-12411-02 | 60°C Rated
Price: 19.94 GBP
Rating: 5 (1 reviews)

Premium Quality Replacement Part for 2-Stroke Outboards

This precision-engineered thermostat is a critical component for your Yamaha outboard's cooling system. It is designed to regulate the engine temperature at 50°C (122°F), ensuring optimal combustion and preventing salt crystal buildup within the cooling passages. A failing thermostat can lead to overheating or inefficient running; this direct-fit replacement restores factory-standard thermal regulation.

RELIABILITY: Manufactured using marine-grade brass and stainless steel components to resist corrosion in harsh saltwater environments.

Key Features

✔ Direct fit for 40HP & 50HP 2-Stroke models
✔ Accurate 50°C (122°F) opening threshold
✔ High-grade anti-corrosive materials
✔ Meets or exceeds OEM performance standards

Technical Specs

Opening Temp:	50°C / 122°F
Material:	Brass / Stainless Steel
Outer Diameter:	34mm
Inner Diameter:	27mm
Height:	17mm

Compatibility / Fitment Guide

Engine Type	Horsepower	Year/Notes
Yamaha 2-Stroke	40 HP / C40 / P40	1986 - 2005
Yamaha 2-Stroke	50 HP / C50 / P50 / PRO50	1986 - 2005
Yamaha 2-Stroke	3 HP to 250 HP	Broad application across most V4/V6 & small 2-strokes

OEM Cross Reference

Yamaha OEM	6E5-12411-02, 6E5-12411-00, 6E5-12411-01, 6E5-12411-30
Sierra Marine	18-3540, 18-3623
Mallory Marine	9-43035

Questions & Answers

Is this a genuine original part?

This is a premium quality aftermarket replacement part, manufactured to meet or exceed original equipment (OE) standards for fitment and performance.

How do I know if it is compatible?

We recommend checking the SKU/MPN and Cross Reference list provided above. If your original part number starts with 6E5-12411, this is the correct part.

Why is the opening temperature set to 50°C?

Yamaha 2-stroke outboards utilize a 50°C (122°F) thermostat to ensure the engine warms up quickly for efficient combustion while remaining cool enough to prevent mineral deposits from salt water from solidifying in the cooling jackets.

Note: Please verify your original part number against the references above before purchasing. Ships from 4boats.co.uk.

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Thermostat for Yamaha Outboard 2-Stroke Engines | Replaces 688-12411-10 / 6H3-12411-11 / 6E5-12411-02 | 60°C Rated