Towing Equipment› Hitches

SIERRAMARINE

INSERT CUP

$18.67

SKU: S08C 18-3113

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 18-3113 is an insert cup for Mercury Marine outboard engines. It is designed for use with 3.5-10 Hp engines manufactured between 1974 and 1986. This part replaces Mercury part numbers 46894, 70977, and 70977Y, as well as Mallory 9-43601 and GLM 12817.

Fitment

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

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Specifications

BrandSIERRAMARINE
Part NumberS08C 18-3113

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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