Sierra 18-99399 Voltage Regulator/Rectifier, Replaces 583076, for Johnson/Evinrude 4/6 Cylinder 35 Amp Outboards

The Sierra 18-99399 Voltage Regulator/Rectifier is a 35 amp replacement unit built for Johnson/Evinrude outboard charging systems. It regulates alternator output and rectifies AC current to DC to keep the battery properly charged and protect onboard electronics from voltage spikes. This unit is designed for 6-cylinder Johnson/Evinrude outboards rated 150, 155, 175, 185, and 235 HP, as well as 4-cylinder 110, 115, and 140 HP outboards equipped with the 35 amp charging upgrade.

The regulator/rectifier is a direct-fit replacement for the OEM part numbers listed below, so it installs using the factory wiring harness and mounting points without modification. It measures 8 x 6 x 4 inches and weighs 1.1 pounds.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-99399
• Universal Product Code: 808282394325
• Category: Evinrude Outboard Rectifier Regulator
• Amperage: 35 Amp
• Compatible Engine Brand: Johnson/Evinrude
• Cylinder Configuration: 4-Cylinder and 6-Cylinder
• Product Dimensions: 8 x 6 x 4 inches
• Weight: 1.1 pounds

Fitment

• Johnson/Evinrude 150, 155, 175, and 185 HP (6 cylinder), 1984-1991
• Johnson/Evinrude 235 HP (6 cylinder), 1984-1991
• Johnson/Evinrude 110, 115, and 140 HP (4 cylinder with 35 Amp upgrade), 1992

Replaces (OEM)

• 583076
• 582904
• 584423
• 583268
• 395204
• 395391
• 878335
• 721876

Frequently Asked Questions

What does the Sierra 18-99399 voltage regulator/rectifier do? It regulates the alternator's output voltage and converts AC current to DC on Johnson/Evinrude outboards, keeping the battery properly charged and protecting onboard electronics from overcharging.

Which Johnson/Evinrude engines does part 18-99399 fit? It fits Johnson/Evinrude 6-cylinder outboards rated 150, 155, 175, 185, and 235 HP from 1984-1991, and 4-cylinder 110, 115, and 140 HP outboards from 1992 equipped with the 35 amp charging upgrade.

Is 18-99399 a 35 amp or 16 amp regulator? The Sierra 18-99399 is rated at 35 amps, matching the charging output of the Johnson/Evinrude engines it replaces.

What OEM part numbers does Sierra 18-99399 replace? Sierra 18-99399 replaces OEM numbers 583076, 582904, 584423, 583268, 395204, 395391, 878335, and 721876.

What are the dimensions and weight of this regulator/rectifier? The Sierra 18-99399 measures 8 x 6 x 4 inches and weighs 1.1 pounds.

Will this unit work with a 4-cylinder Johnson/Evinrude outboard? Yes, 18-99399 fits 4-cylinder 110, 115, and 140 HP Johnson/Evinrude outboards from 1992 that have the 35 amp charging upgrade, in addition to the 6-cylinder applications it covers.

Does the Sierra 18-99399 install with the factory wiring? Yes, since it is a direct replacement for the listed OEM numbers, it connects to the existing factory wiring harness and mounting points on the applicable Johnson/Evinrude outboard.

Is Sierra 18-99399 a genuine OEM part or an aftermarket replacement? It is an aftermarket replacement manufactured by Sierra, engineered to replace the OEM Johnson/Evinrude numbers 583076, 582904, 584423, 583268, 395204, 395391, 878335, and 721876.

Can I use 18-99399 on a 6-cylinder 235 HP Evinrude? Yes, the 235 HP (6 cylinder) Johnson/Evinrude outboard from 1984-1991 is a listed application for the Sierra 18-99399 regulator/rectifier.

What is included when I order this part? You receive one Sierra 18-99399 voltage regulator/rectifier unit, sized for direct installation on the applicable Johnson/Evinrude outboard charging system.