# 855676003 Mercury MerCruiser Thermostat | Genuine Quicksilver OEM Part

## 🔧 Product Description

**Genuine Quicksilver FourStroke Thermostat - Part Number: 855676003**

A genuine Quicksilver thermostat for selected Mercury and Mariner FourStroke outboards. This thermostat is part of the 855676 / 825212 thermostat family and helps control operating temperature in small and mid-range FourStroke cooling systems.

## ⚙️ Key Features

-   Genuine Quicksilver OEM thermostat
-   Correct Mercury part number 855676003
-   Common 60°C / 140°F FourStroke thermostat application
-   Related to 825212001, 825212T02 and 855676A1 references
-   Used across selected Mercury / Mariner 13.5HP to 50HP FourStroke models, with additional FourStroke applications where specified

## 🚤 Compatibility

### Commonly used on

-   Mercury / Mariner FourStroke cooling system thermostat applications

### Typically suits

-   Engine models:
-   Mercury / Mariner 13.5HP FourStroke International applications where 855676003 is specified
-   Mercury / Mariner 15HP FourStroke applications where 855676003 is specified
-   Mercury / Mariner 25HP FourStroke applications where 855676003 is specified
-   Mercury / Mariner 30HP FourStroke - USA serial 0G760300 to 1B226999
-   Mercury / Mariner 30HP FourStroke - Belgium serial 0P017000 to 0P400999
-   Mercury / Mariner 40HP FourStroke - USA serial 0G231123 and up
-   Mercury / Mariner 40HP FourStroke - Belgium serial 0P017000 and up
-   Mercury / Mariner 40HP 3-cylinder FourStroke - serial 1C049739 and up where specified
-   Mercury / Mariner 45HP FourStroke applications where 855676003 is specified
-   Mercury / Mariner 50HP FourStroke - USA serial 0G231123 to 0T178499
-   Mercury / Mariner 40HP, 50HP and 60HP EFI FourStroke applications where the 855676003 thermostat family is specified
-   HP Range: 13.5HP - 60HP primary FourStroke range, with additional FourStroke applications where specified
-   Engine Type: Mercury / Mariner FourStroke outboard
-   Temperature Rating: commonly 60°C / 140°F thermostat family

## 🔌 Function

The thermostat opens and closes with engine temperature to regulate cooling water flow and maintain stable engine operating temperature.

## ⚠️ Common Signs of Failure

-   Overheating
-   Engine running too cold
-   Poor warm-up or idle quality
-   Temperature warning
-   Thermostat stuck, corroded or blocked by debris

## 🔄 Supersession & Cross Reference

### OEM Supersession Chain

-   855676003 current thermostat service reference
-   855676A1 related thermostat kit reference
-   825212001 related OEM thermostat reference
-   825212T02 related service reference
-   855676 earlier OEM reference

### OEM / Related Numbers

-   855676003
-   855676
-   855676A1
-   825212001
-   825212
-   825212T02

### Aftermarket / Verified Equivalents

-   Sierra: 18-3642
-   Recmar: REC825212T02
-   Yamaha equivalent family: 6G8-12411-00 / 6G8-12411-01

## 📦 Condition

-   Genuine Quicksilver part
-   Brand new
-   Supplied in original or equivalent packaging

## Details

- **Price:** 44.0 AUD
- **Vendor:** Quicksilver
- **Type:** Cooling System
- **Tags:** Quicksilver Marine Parts | Oils, Service Kits & Engine Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 44.00 AUD | In stock |

## Images

- 855676003 Mercury MerCruiser Thermostat | Genuine Quicksilver OEM Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/855676003-mercury-mercruiser-thermostat-genuine-quicksilver-oem-part)
> Updated: 2026-09-06