Exterior Components› Body Panels and Components

SIERRAMARINE

MOLDED HOSE

$61.36

SKU: S08C 18-70939

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 SIERRAMARINE 18-70939 is a molded hose designed for marine engine cooling systems. It serves as a replacement part for specific Mercruiser V6 and V8 engines. This hose connects the thermostat housing to the starboard manifold, ensuring proper coolant flow for optimal engine performance and temperature regulation.

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 18-70939

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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