Mercury – Thermostat 143 Degree F | Cooling System Component | OEM-Grade Construction | 8M6010302

Overview

Out on the water, few things matter more than an engine that warms up the right way and stays in its comfort zone. You feel it when you push off from the dock — that quiet confidence in knowing your outboard is running at the temperature it was built for. The Quicksilver 8M6010302 Thermostat brings that kind of peace of mind. It’s small, sure, but it plays a huge role in keeping your motor steady, responsive, and ready for long days exploring hidden coves or riding back in through a choppy inlet. When the temperature is right, everything just works smoother, and you can focus on the water instead of what’s happening under the cowling.

Key Features

• Maintains proper operating temperature for select 6–55hp Evinrude, Johnson, and OMC two-stroke outboards
• Designed to meet OEM specifications for 143°F operation
• Durable thermostat engineered for consistent, reliable heat regulation
• Thermostat only — seals, gaskets, and mounting hardware sold separately
• Built to match exact fit and performance requirements of the original part

Engine & Boat Compatibility

• Fits select Evinrude, Johnson, and OMC two-stroke outboards from 6–55hp
• Compatible with V4 and V6 Crossflow outboard engines
• Commonly used on runabouts, skiffs, tiller-steered fishing boats, and lightweight utility hulls
• Works with standard two-stroke cooling systems found on these models

Performance & Practical Benefits

When a thermostat performs exactly as it should, you don’t have to think about it — and that’s the beauty of this part. At 143°F, the engine warms quickly but avoids the stress caused by running too hot. You’ll notice smoother idle, cleaner throttle response, and a steadier feel when cruising. It helps maintain proper fuel burn, protects internal components, and keeps your outboard from laboring unnecessarily.

On older two-stroke motors especially, temperature swings can lead to everything from fouled plugs to excessive wear. This Quicksilver thermostat delivers tight, predictable control so your engine stays in the zone where it’s happiest. Installation is simple, and the moment you start the motor again, you’ll feel the difference — that quiet steadiness that tells you your cooling system is doing exactly what it should.

Why Buy OEM

In the world of outboard parts, thermostats aren’t something you want to gamble on. OEM-grade components like this Quicksilver unit are built to match the precise heat range, opening rate, and durability your engine was engineered around. Aftermarket versions often drift out of spec, stick open, or fail early, leaving your motor running too cold or too hot. With Quicksilver, you get reliability you can trust season after season.

If a friend on the dock asked for advice, you’d probably say the same thing: use the part that’s built to the original standard. It’s the simplest way to protect your outboard and keep your maintenance predictable.

FAQ

Q1: Which engines does this thermostat fit?

It’s made for select 6–55hp Evinrude, Johnson, and OMC two-stroke outboards, including V4 and V6 Crossflow models.

Q2: How is this different from aftermarket thermostats?

It matches OEM heat specs and reliability, ensuring stable temperature regulation.

Q3: How do I confirm if this is the right part?

Check your service manual or match your engine model with the original part number.

Q4: Can it be used in both freshwater and saltwater?

Absolutely — it’s built to perform consistently in either environment.

Q5: Is installation easy for most boaters?

Yes. With basic tools and your manual, it’s a straightforward replacement.