Sierra 18-5163 Ignition Coil, OMC 581130 Equivalent, for Johnson/Evinrude 18-25 HP Outboards (1973-1976)

The Sierra 18-5163 is an ignition coil built for Johnson/Evinrude outboard motors, engineered to meet or exceed the performance of the original equipment part it replaces. It generates the high-voltage spark needed to fire the spark plugs at the correct timing, and is a direct fit for the specific horsepower and model-year combinations listed below. The coil features a female connector for a secure, factory-style electrical connection and is designed for screw-in or bolt-on installation, making it a straightforward replacement for outboards showing signs of a failing coil such as hard starting, misfiring, or intermittent power loss.

Sierra manufactures marine parts to withstand the harsh marine environment, and this ignition coil is no exception. It ships as a single unit and carries Sierra's standard customer satisfaction warranty. Confirm your outboard's horsepower rating and model year against the fitment details below before ordering, since ignition coil requirements vary by year even within the same horsepower class.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-5163
• UPC: 030999318404
• Item Dimensions: 0.39 x 0.39 x 0.39 inches
• Weight: 0.56 pounds
• Connector Gender: Female
• Installation Type: Screw-In or Bolt-On
• Vehicle Service Type: Outboard Motor
• Coil Quantity Required: 1
• Unit Count: 1

Fitment

• Johnson/Evinrude 18 HP, 1973
• Johnson/Evinrude 20 HP, 1973
• Johnson/Evinrude 25 HP, 1973-1976

Replaces (OEM)

• OMC 581130

Frequently Asked Questions

What outboard motors does the Sierra 18-5163 ignition coil fit? The Sierra 18-5163 fits Johnson/Evinrude 18 HP outboards from 1973, 20 HP outboards from 1973, and 25 HP outboards from 1973 through 1976.

Is the Sierra 18-5163 a direct OEM replacement? Yes, it is the equivalent of OMC part number 581130 and is designed to meet or exceed the performance of the original coil it replaces.

How many coils does my outboard need? For the 18, 20, and 25 HP Johnson/Evinrude applications covered by the 18-5163, only 1 coil is required per engine.

What are the dimensions of this ignition coil? The Sierra 18-5163 measures 0.39 x 0.39 x 0.39 inches.

How much does the 18-5163 ignition coil weigh? It weighs 0.56 pounds.

What type of electrical connector does the 18-5163 use? The coil uses a female connector for a secure, factory-style electrical connection.

How is the Sierra 18-5163 installed? This ignition coil uses a screw-in or bolt-on installation type, consistent with the original equipment mounting on covered Johnson/Evinrude outboards.

Will the 18-5163 fit a 1977 model year 25 HP Johnson/Evinrude? No, the Sierra 18-5163 is specified for the 25 HP application from 1973 through 1976; outboards outside that range require a different coil.

What comes in the box with the Sierra 18-5163? The package includes one Sierra 18-5163 ignition coil, sold as a single unit.

Is the Sierra 18-5163 covered by a warranty? Yes, the Sierra 18-5163 ignition coil is covered under Sierra's customer satisfaction warranty.

What symptoms indicate my outboard needs a new ignition coil like the 18-5163? Hard starting, misfiring, or intermittent loss of power on a covered Johnson/Evinrude 18, 20, or 25 HP outboard can indicate a failing ignition coil, which the 18-5163 is designed to replace.