Sierra 18-5224-9 Marine Spark Plug Wire Terminal, Replaces Mercury 20121, Package of 10
Sierra 18-5224-9 Marine Spark Plug Wire Terminal, Replaces Mercury 20121, Package of 10
The Sierra 18-5224-9 is a marine spark plug wire terminal designed to attach to ignition wire on outboard motors, sold as a package of 10 terminals. Built from brass for reliable electrical conductivity and corrosion resistance in the marine environment, this terminal is the connection point where ignition wire meets the spark plug boot, completing the circuit that fires the spark plug. Because it comes packaged in a quantity of 10, it is well suited for shops and boat owners servicing multiple cylinders or keeping spares on hand for ignition wire repairs and rebuilds.
Sierra engineers its ignition parts to meet or exceed the original equipment they replace, and this terminal is built to withstand the vibration, heat, and moisture exposure typical of outboard engine compartments. It is a direct equivalent for several OEM terminal numbers used across outboard and sterndrive ignition systems, making it a straightforward replacement when rebuilding ignition wire assemblies or repairing a damaged terminal connection.
Specifications
- Brand: Sierra
- Manufacturer Part Number: 18-5224-9
- Package Quantity: 10 terminals per package
- Material: Brass
- Product Dimensions: 0.39 x 0.39 x 0.39 inches
- Weight: 0.03 pounds
- UPC: 808282164911
- Application: Ignition wire terminal for outboard motors
Fitment
Designed to fit outboard motor ignition wire applications.
Replaces (OEM)
- Johnson/Evinrude 510364
- Mercury Marine 20121
- Mercury Marine 8M0084600
Frequently Asked Questions
How many terminals come in the Sierra 18-5224-9 package? The Sierra 18-5224-9 is sold as a package of 10 spark plug wire terminals, making it convenient for servicing an entire outboard motor's ignition wiring or keeping spares on hand.
What is the Sierra 18-5224-9 terminal made of? It is made of brass, which provides good electrical conductivity and resists corrosion in the marine environment where ignition components are exposed to moisture.
What OEM part numbers does the 18-5224-9 terminal replace? It replaces Johnson/Evinrude 510364, Mercury Marine 20121, and Mercury Marine 8M0084600, so it can be used as a direct equivalent for any of those OEM terminal numbers.
Is the Sierra 18-5224-9 genuine Sierra or aftermarket? It is a genuine Sierra part, manufactured by Sierra as an aftermarket replacement engineered to meet or exceed the original equipment terminal it replaces.
What size is each spark plug wire terminal? Each 18-5224-9 terminal measures 0.39 x 0.39 x 0.39 inches, a compact size that fits onto ignition wire before the spark plug boot is attached.
How much does the 18-5224-9 package weigh? The package of 10 Sierra 18-5224-9 terminals weighs 0.03 pounds.
What is a spark plug wire terminal used for? A spark plug wire terminal, like the Sierra 18-5224-9, connects ignition wire to a spark plug boot, forming the electrical connection needed to deliver spark to the plug on an outboard motor.
Does the 18-5224-9 come with installation instructions or crimping tools? The package contains only the brass terminals themselves; no crimping tool or instructions are included with the 18-5224-9.
Will the 18-5224-9 terminal fit any outboard motor ignition wire? The 18-5224-9 is designed as an ignition wire terminal for outboard motors; check that your ignition wire gauge matches the terminal before installing.
What warranty applies to the Sierra 18-5224-9? As a genuine Sierra product, the 18-5224-9 qualifies for Sierra's Customer Satisfaction Warranty, which covers defects in workmanship and materials for the useful life of the product.
Can the 18-5224-9 be used to repair a single damaged terminal instead of rewiring the whole ignition harness? Yes, since the 18-5224-9 is sold in a package of 10, it can be used to replace just one damaged terminal or several as needed during ignition wire repairs.