Sierra 18-4218 Brass Drain Tap, 1/4 Inch NPT, for MerCruiser Cylinder Blocks and Exhaust Manifolds

The Sierra 18-4218 Drain Tap is a small brass drain valve used to drain water from MerCruiser cylinder blocks and exhaust manifolds during winterization, maintenance, or repair work. Threaded with a 1/4 inch NPT connection, it installs directly into the drain port on the engine block or manifold casting, allowing the cooling system to be emptied of raw water quickly and cleanly. The tap is constructed of solid brass for corrosion resistance in a marine environment, and features a polished copper-tone finish with a single lever-style handle for easy on/off operation without tools.

This is a fit-specific replacement part, so it is intended to match the original drain tap location and thread size used on applicable MerCruiser cylinder blocks and exhaust manifolds. Each Sierra replacement part is built to meet or exceed the performance of the original equipment part it replaces, making it a reliable choice for routine winterizing and engine service.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-4218
• Product Name: Drain Tap
• Material: Brass
• Finish: Polished
• Color: Copper
• Thread Size: 1/4 inch NPT
• Handle Type: Lever, single handle
• Included Components: Drain Tap
• Weight: 0.11 pounds
• UPC: 030999317650

Fitment

Fits MerCruiser cylinder blocks and exhaust manifolds. This is a fit-specific part, so confirm compatibility with your authorized dealer before ordering.

Frequently Asked Questions

What thread size does the Sierra 18-4218 drain tap use? The Sierra 18-4218 Drain Tap has a 1/4 inch NPT thread, matching the drain port on applicable MerCruiser cylinder blocks and exhaust manifolds.

What is the 18-4218 drain tap made of? It is made of solid brass with a polished, copper-tone finish, which resists corrosion in a marine cooling system environment.

What does this drain tap fit? The Sierra 18-4218 fits MerCruiser cylinder blocks and exhaust manifolds. Because it is a fit-specific part, confirm the drain port thread size on your engine before ordering.

How much does the 18-4218 drain tap weigh? The Sierra 18-4218 Drain Tap weighs 0.11 pounds.

Is the Sierra 18-4218 an OEM-equivalent part? Yes, Sierra states this drain tap meets or exceeds the performance of the original equipment part it replaces on MerCruiser cylinder blocks and exhaust manifolds.

How does the drain tap operate? The 18-4218 uses a single lever-style handle, so water can be drained from the cylinder block or exhaust manifold by turning the handle without needing tools.

What is included when I order part number 18-4218? The listing includes one Sierra 18-4218 Drain Tap; no additional hardware or gasket is specified as included.

Why would I need to replace a drain tap like the 18-4218? A drain tap on a cylinder block or exhaust manifold can corrode, seize, or leak over time, so the brass Sierra 18-4218 is used as a direct replacement to restore reliable draining for winterizing or service.

Is the 18-4218 genuine Sierra or aftermarket? The 18-4218 is a genuine Sierra part, sold under Sierra's own part number as a replacement drain tap for MerCruiser applications.

What color and finish does the 18-4218 have? It has a polished finish with a copper color, consistent with its solid brass construction.