Ignitions and Electrical› Charging Systems

SIERRAMARINE

VOLTAGE REGULATOR, MERCURY

$667.87

SKU: S08C 18-99421

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Easy — 1–2 hours

Description

The Sierra Marine 18-99421 Voltage Regulator is designed as a high-quality, aftermarket replacement for original Mercury/Mercruiser parts, specifically for 470 water-cooled engines. This essential component manages the electrical output from your engine's charging system, preventing overcharging and undercharging, which can extend the life of your battery and other electrical components. Constructed to meet or exceed OEM specifications, this voltage regulator offers reliable performance in harsh marine environments. It replaces several OEM part numbers, including Mercury Marine 8M0084494, 883072T1, 99502A1, 99502A10, 99502A13, and others.

Fitment

Fitment Guaranteed

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on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandSIERRAMARINE
Part NumberS08C 18-99421

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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