Engines and Components› Engine Covers, Pans and Dress-Up Components

SIERRAMARINE

GASKET, OIL DRAIN

$18.83

SKU: S08C 18-0657

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

Beginner — under 30 min

Description

The Sierra 18-0657 is a replacement drain plug gasket designed for marine lower units. This essential sealing component creates a watertight seal between the drain plug and the lower unit housing, preventing gear oil leakage and water intrusion.

Key features include a precision-engineered gasket that ensures a proper seal on lower unit drain plugs, preventing gear oil leaks and protecting against water contamination. It is a direct replacement for worn or damaged OEM gaskets and is manufactured to meet or exceed OEM specifications.

Fitment

Fitment Guaranteed

Don’t gamble
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 18-0657

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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