Gaskets and Seals› Engine Gaskets and Seals

SIERRAMARINE

OIL SEAL

$23.43

SKU: S08C 18-0525

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 18-0525 is a rubber oil seal designed for Mercury and Mariner outboard motors. It features an outside diameter of 0.628 inches, a shaft size of 0.390 inches, and a width of 0.124 inches. Sierra Marine engine parts are built 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 18-0525

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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