Mercury – Oil Temperature Gauge | Dual Scale | Gray Face | 2-1/8" (52 mm) | 79-8M0065978

Overview

The Mercury Oil Temperature Gauge (79-8M0065978) gives you quick, accurate readings of your engine’s oil temperature so you can make sure everything’s running in the safe zone. The dual-scale display reads in both Fahrenheit and Celsius, letting you monitor in your preferred unit. The gray face, clean white numerals, and glass lens provide a modern OEM look that matches other Mercury gray-face gauges perfectly. It fits a standard 2-1/8" (52 mm) dash hole and connects to SmartCraft systems equipped with oil temperature sensors.

Key Features

• Dual-Scale Readout (°F / °C) – Displays oil temperature in both English and Metric units.
• Gray Face & Glass Lens – Sleek, high-contrast design for easy visibility.
• Standard 2-1/8" (52 mm) Fit – Installs easily in most dash panels or helm layouts.
• SmartCraft Integration – Works with Mercury systems that have oil temperature sensors.
• Accurate Monitoring – Provides real-time oil temperature feedback to protect your engine.
• Marine-Grade Build – UV-stable, corrosion-resistant, and tested for vibration and heat.
• OEM Fit & Finish – Matches Mercury’s gray-face gauge line for a cohesive factory appearance.

Compatibility

• Fits: Mercury SmartCraft-equipped boats (functionality depends on engine model and installed sensors)

Performance & Practical Benefits

This gauge helps you protect your engine by keeping you aware of your oil temperature at all times. It gives clear, responsive readings so you’ll know when your system is operating normally — or when it’s time to ease off the throttle. The gray face adds a clean, modern look to your dash and blends perfectly with the rest of your Mercury instruments.

Why Buy OEM

Mercury Marine gauges are built for real-world boating. Each unit is tested for accuracy and durability in the harshest marine conditions — salt, sun, and vibration. With genuine OEM parts, you get factory-level precision, dependable SmartCraft integration, and a product that lasts season after season.

FAQ

Q1: What temperature scales does it display?
It reads oil temperature in Fahrenheit and Celsius.

Q2: What dash hole does it fit?
A standard 2-1/8" (52 mm) opening.

Q3: Does it work with all Mercury engines?
It’s designed for SmartCraft-capable engines with oil temperature sensors.

Q4: How easy is it to install?
It installs like any other Mercury gauge — quick and straightforward with SmartCraft wiring.

Q5: Is this an OEM part?
Yes — it’s a genuine Mercury Marine gauge, built to factory specifications.