Drivetrain› Automatic Transmissions and Components

SIERRAMARINE

THRUST WASHER

$50.92

SKU: S08C 18-4220

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

Beginner — under 30 min

Description

The Sierra Marine 18-4220 is a thrust washer used at the forward end of the propeller shaft. Its function is to center the forward end of the propeller to the shaft. This part replaces Mercruiser part numbers 13171 and 77987, and is compatible with V-6 Outboards and Mercruiser Sterndrives.

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 18-4220

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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