Sierra Voltage Regulator/Rectifier 18-99424, 35 Amp, Replaces 586000, Fits Johnson/Evinrude 175-300 HP 6/8 Cylinder

The Sierra 18-99424 is a 35 amp voltage regulator/rectifier built for Johnson and Evinrude outboard engines. It manages the output from the engine's charging system, converting alternating current to direct current and regulating voltage to protect the battery and onboard electronics from overcharging. This is a direct-fit replacement for the factory regulator/rectifier used on Johnson/Evinrude 6-cylinder and 8-cylinder outboards, restoring reliable charging performance on engines whose original unit has failed or is showing signs of erratic charging, battery drain, or no-charge conditions.

The unit is a factory-style form and mounts using the original attachment points on compatible engines, letting it swap in for the OEM part without modification. It weighs 1 pound, making it a straightforward drop-in replacement for anyone comfortable with basic marine electrical work.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-99424
• Product Type: Voltage Regulator/Rectifier
• Amperage: 35 Amp
• Weight: 1 pound
• Package Dimensions: 7.68 x 5.39 x 3.35 inches
• UPC: 736983852892
• OEM Cross-Reference: 586000, 586272, 583266, 583689, 584424, 878334

Fitment

• Johnson/Evinrude 175, 185, 200 and 225 HP (6 cylinder) outboards, 1986-1992
• Johnson/Evinrude 250, 275 and 300 HP (8 cylinder) outboards, 1985-1992

Replaces (OEM)

• 586000
• 586272
• 583266
• 583689
• 584424
• 878334

Frequently Asked Questions

What does the Sierra 18-99424 voltage regulator/rectifier do? It converts the alternating current produced by the outboard's charging system into direct current and regulates the voltage sent to the battery, preventing overcharging and protecting onboard electronics on Johnson/Evinrude outboards.

Which outboard engines does the 18-99424 fit? It fits Johnson/Evinrude 175, 185, 200 and 225 HP 6-cylinder outboards from 1986-1992, and Johnson/Evinrude 250, 275 and 300 HP 8-cylinder outboards from 1985-1992.

What OEM part numbers does the 18-99424 replace? The Sierra 18-99424 replaces OEM numbers 586000, 586272, 583266, 583689, 584424 and 878334.

Is the Sierra 18-99424 a direct OEM replacement or an aftermarket part? It is an aftermarket voltage regulator/rectifier manufactured to replace the listed OEM part numbers on Johnson/Evinrude engines, functioning as a direct swap for the original unit.

How much does the 18-99424 regulator/rectifier weigh? The Sierra 18-99424 weighs 1 pound.

What are the dimensions of the 18-99424? Package dimensions for this regulator/rectifier are 7.68 x 5.39 x 3.35 inches.

What amperage rating does the 18-99424 have? It is rated at 35 amps.

Will the 18-99424 fit a 4-cylinder Johnson/Evinrude outboard? No, the fitment covers 6-cylinder 175-225 HP models (1986-1992) and 8-cylinder 250-300 HP models (1985-1992); it is not listed as fitting 4-cylinder engines.

Does the 18-99424 include mounting hardware? The listing covers the voltage regulator/rectifier unit itself; no additional accessories are specified.

Can I use the 18-99424 to fix a no-charge or battery drain issue on my outboard? Yes, a failed voltage regulator/rectifier is a common cause of no-charge or erratic charging symptoms, and the 18-99424 is designed to replace the original unit on compatible Johnson/Evinrude engines.

What is the UPC for the Sierra 18-99424? The UPC for this product is 736983852892.