Mercury – Quicksilver 25W-40 4-Stroke Marine Engine Oil, 1 Quart | Marine Engine Oil | Standard Finish | 8M0078619

Overview

There’s something comforting about knowing your engine is running on clean, trusted oil — that steady hum, that smooth throttle response, that quiet confidence as you head out from the dock. When you spend your weekends on the water, you start to appreciate the small things that keep every trip easy and trouble-free. Quicksilver 25W-40 4-Stroke Marine Engine Oil, part number 8M0078619, is one of those essentials you reach for because it never lets you down. It delivers the kind of protection that makes boating feel simpler, safer, and far more enjoyable.

Key Features

• Designed specifically for four-stroke marine engines

• Formulated for corrosion resistance and dependable wear protection

• Special viscosity modifiers support high-rpm performance

• Twenty-five weight forty viscosity

• Thirty-two ounce bottle size

• Mercury Marine part number 8M0078619

Engine & Boat Compatibility

• Suitable for a wide range of Mercury four-stroke outboards

• Works well in Mercury sterndrive and inboard systems requiring 25W-40 oil

• Compatible with many other marine engine brands using four-stroke lubrication

• Seen on pontoons, bass boats, center consoles, cruisers, and versatile family boats

Performance & Practical Benefits

The difference this oil makes shows up in the way your engine behaves. It fires up cleanly, settles into a smooth idle, and holds steady when the waves get choppy or the load gets heavy. The viscosity stays consistent, giving your internal components the cushion they need to operate without grinding, overheating, or wearing down before their time.

High-rpm outboards benefit from its stability, especially during long runs when heat and pressure can push lesser oils to their limits. This blend keeps things smooth and controlled, and you’ll feel that when you throttle up and the engine responds without hesitation. The corrosion protection is another quiet hero here. Salt, humidity, and temperature swings are constant companions on the water, and this oil helps create a durable barrier that lets your engine age more gracefully. It supports easier upkeep, fewer surprises during maintenance, and a stronger sense of reliability each time you head out.

Why Buy OEM

Choosing a genuine Mercury Marine part is really about eliminating guesswork. You know the oil was engineered, tested, and refined for the exact conditions your engine faces. It performs right the first time and stays consistent through the whole season. Aftermarket oils often promise a lot but fall short when marine environments push them harder than automotive blends ever endure. With OEM oil, you get long-term protection, predictable performance, and peace of mind — the kind of advice any experienced boater would gladly pass along.

FAQ

Q1: Which Mercury engines does Quicksilver 25W-40 4-Stroke Marine Engine Oil fit?
It works with most Mercury four-stroke outboards, sterndrives, and inboards requiring a 25W-40 oil.

Q2: What makes this oil different from aftermarket options?
It’s engineered for marine heat, moisture, and high-rpm conditions, offering stronger corrosion and wear protection.

Q3: How do I know if it’s the correct oil for my engine?
Check your owner’s manual. If it specifies twenty-five weight forty for four-stroke lubrication, this is the right match.

Q4: Can this oil be used in both saltwater and freshwater environments?
Yes, its corrosion-resistant formulation is built for either setting.

Q5: Is installation straightforward?
Very. If you can perform a basic oil change, you’ll find this bottle easy to pour and work with.