Sierra 18-99250 16 Amp Stator for Mercury and Yamaha 2/3/4-Cylinder Outboards, Replaces 852387A6

The Sierra 18-99250 is a 16 Amp stator built for Mercury and Yamaha outboards, supplying the charging current the ignition and electrical system need to keep the battery topped off and the engine running reliably. It is designed for use in a marine environment, where it has to stand up to constant vibration, heat cycling, and exposure to moisture around the powerhead.

This stator is compatible with Mercury and Yamaha 25 HP 2-cylinder engines from 1998-2005, 30 and 40 HP 3-cylinder engines from 2002-2005, and 40, 50, and 60 HP 4-cylinder engines from 2002-2005, on Electric Start, 4-Stroke models with a 4-Pin Connector. It is a direct fit for these engine families, delivering the same 16 Amp output as the original equipment part it replaces.

Because charging systems on these Mercury and Yamaha outboards were produced under a long list of part numbers over the years, this stator is cross-referenced to the OEM numbers below so you can confirm it matches what is currently on your engine before ordering.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-99250
• Output: 16 Amp
• Cylinder Compatibility: 2/3/4 Cylinder
• Engine Type: Electric Start, 4-Stroke
• Connector: 4-Pin Connector
• Compatible Engine Brands: Mercury, Yamaha
• Weight: 3 pounds
• Package Dimensions: 9 x 7 x 2.5 inches
• UPC: 808282394158

Fitment

• Mercury and Yamaha 25 HP (2 Cyl.), 1998-2005, Electric Start, 4-Stroke, 4-Pin Connector
• Mercury and Yamaha 30 and 40 HP (3 Cyl.), 2002-2005, Electric Start, 4-Stroke, 4-Pin Connector
• Mercury and Yamaha 40, 50, and 60 HP (4 Cyl.), 2002-2005, Electric Start, 4-Stroke, 4-Pin Connector

Replaces (OEM)

• 174-2387
• 398852387A 3
• 398-852387A 4
• 398-852387A 6
• 398-852387T 6
• 398-852387T 7
• 398-852387T 9
• 65W-85510-10-00
• 852387A 4
• 852387A 6
• 852387T 6
• 852387T 7

Frequently Asked Questions

What engines does the Sierra 18-99250 stator fit? It fits Mercury and Yamaha 25 HP 2-cylinder outboards from 1998-2005, 30 and 40 HP 3-cylinder outboards from 2002-2005, and 40, 50, and 60 HP 4-cylinder outboards from 2002-2005, all with Electric Start, 4-Stroke, 4-Pin Connector configurations.

How many amps does this stator put out? The Sierra 18-99250 is rated at 16 Amp output.

Will the Sierra 18-99250 work as a direct replacement for my old stator? Yes, the 18-99250 is a direct fit for the Mercury and Yamaha engines listed in its fitment range and cross-references to the same OEM part numbers used on those engines, including 852387A 6 and 852387T 7.

What OEM part numbers does the 18-99250 replace? This stator cross-references to 174-2387, 398852387A 3, 398-852387A 4, 398-852387A 6, 398-852387T 6, 398-852387T 7, 398-852387T 9, 65W-85510-10-00, 852387A 4, 852387A 6, 852387T 6, and 852387T 7.

Does the connector type matter for this stator? Yes, the 18-99250 uses a 4-Pin Connector, so confirm your engine's charging harness matches this connector style before installing.

How much does the 18-99250 stator weigh? It weighs 3 pounds.

Is this stator suitable for use on the water? The Sierra 18-99250 is designed for use in a marine environment, making it suitable for the vibration, heat, and moisture exposure typical of outboard engine bays.

Does the 18-99250 work on both electric start and manual start engines? It is built for Electric Start, 4-Stroke outboards in the listed Mercury and Yamaha fitment range.

Can I use the same stator on a 2-cylinder and a 4-cylinder outboard? The 18-99250 covers 2, 3, and 4-cylinder Mercury and Yamaha engines within its stated fitment, so the same part number applies across those cylinder counts as long as the HP and year range match.

What is included when I order the Sierra 18-99250? You receive one Sierra 18-99250 16 Amp stator, ready to install in place of the original unit on your Mercury or Yamaha outboard.