This 12V 50A alternator is a direct-fit replacement for Mercury/Mariner 3.0L V6 2-stroke outboard engines that use OEM alternator kit 821663A1. Supplied as Recmar REC821663A1, it’s intended to restore reliable battery charging when the correct match is confirmed.

Before ordering: confirm your engine model/serial range and match the part number on the alternator currently fitted.

• Part: Alternator (with internal regulator)
• Output: 12V / 50A
• Pulley: Single V-belt (V-groove) pulley
• Fits: Mercury/Mariner 3.0L V6 outboards (2-stroke), commonly 225 (Carb/EFI), 250 (EFI) and 300 (EFI) applications
• OEM cross-references: Mercury/Quicksilver 821663A1, 821663, 821663-1
• Other interchanges: Denso 101211-3020, 101211-3021; Sierra 18-6449
• Aftermarket reference: Recmar REC821663A1

Fitment varies by engine version and serial range. Always match the OEM/reference numbers before purchase to avoid ordering the wrong unit.