Mercury – Quicksilver Brass Drain Plug | Cooling System Component | Machined Brass | 16951Q1

Overview

When it’s time to winterize or service your engine, a dependable drain plug makes the job easy. The Mercury Marine 16951Q1 Quicksilver Brass Drain Plug is built for that task — tough, reliable, and simple to install. Designed for MerCruiser sterndrive and inboard engines, it fits most blocks and manifolds with a standard ¼-inch NPT thread. Whether you’re draining coolant, flushing the system, or prepping for storage, this plug gives you a tight seal and the confidence that your engine’s protected from the inside out.

Key Features

• Purpose: Replaces worn or damaged drain plugs for engine blocks and manifolds, making draining and winterizing quick and clean.
• Material: Made from solid machined brass for long-term durability and corrosion resistance.
• Fitment: Standard ¼-inch NPT thread fits most MerCruiser blocks and manifolds.
• Design Detail: Precision-cut threads ensure a snug, leak-free seal every time.
• Performance: Suitable for both closed cooling systems and raw-water-cooled engines.
• Ease of Use: Installs easily with basic hand tools — no special fittings required.

Engine & Boat Compatibility

• Fits most MerCruiser sterndrives and inboard engines, including both raw-water and closed cooling systems.
• Compatible with manifolds and engine blocks across multiple MerCruiser models.
• May also fit other brands of inboard or sterndrive engines using ¼-inch NPT fittings.
• Commonly used on cruisers, runabouts, performance boats, and tow sport setups.

Performance & Practical Benefits

The 16951Q1 drain plug provides a secure seal while allowing quick access for maintenance and winterization. The machined brass construction resists corrosion, even in saltwater, and won’t seize or strip like softer materials. Its tight threads prevent leaks during operation and make it easy to remove when it’s time to drain.

Replacing worn plugs helps you avoid costly freeze damage and keeps the cooling system performing efficiently. Once installed, this plug sits flush and clean — one of those small details that makes seasonal maintenance smoother and faster.

Why Buy OEM

Aftermarket plugs may fit loosely, corrode quickly, or fail to hold a proper seal. The Quicksilver 16951Q1 is a genuine Mercury Marine part, machined to the same precision standards used in Mercury’s factory builds. It’s designed to handle marine conditions — salt, pressure, and vibration — without compromise.

With OEM quality, you get perfect threading, proper material hardness, and a reliable seal every time. It’s an inexpensive part that protects an expensive engine, giving you peace of mind every time you prep your boat for storage or hit the water.

FAQ

Q1: Which engines does this drain plug fit?
It fits most MerCruiser sterndrives and inboards with ¼-inch NPT block or manifold fittings.

Q2: What’s it made of?
It’s made from machined brass, which resists corrosion and threads cleanly for years of use.

Q3: Can it be used on both raw water and closed cooling systems?
Yes — it’s designed for both types of systems.

Q4: How do I install it?
Simply thread it into the drain port with a wrench; no special tools are required.

Q5: Does it work in saltwater?
Yes. The brass construction stands up to salt, moisture, and temperature changes without seizing or pitting.