Sierra Molded Cooling System Hose 18-70930, Replaces Mercruiser 32-52481

The Sierra 18-70930 is a molded cooling system hose engineered for fresh water or raw water cooling systems on inboard and sterndrive boat engines. Unlike straight-cut hose that must be forced into shape, this hose is molded to hold its bend from the factory, so it maintains full, unrestricted water flow through the curve while making installation straightforward. It is built to OEM specifications, meaning fit, form, and function match what the engine was designed around, so there is no guesswork when replacing a cracked, collapsed, or hardened original hose.

Construction is EPDM tubing reinforced with a synthetic knit layer, a combination chosen for marine cooling systems because it resists heat cycling, ozone, and prolonged exposure to fresh or raw water without becoming brittle or swelling. The hose is finished in white. As a direct cross-reference to Mercruiser part number 32-52481, it is intended as a like-for-like replacement in the cooling circuit rather than a universal or trim-to-fit hose.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-70930
• Product Name: Molded Hose
• Category: Mercruiser Hoses
• Material: EPDM tubing with synthetic knit reinforcement
• Color: White
• Weight: 0.2 pounds
• Package Dimensions: 14.0 H x 3.9 L x 12.2 W (centimetres)
• UPC: 808282145972
• Unit Count: 1

Fitment

Designed for fresh water or raw water engine cooling systems using this hose shape; confirm against your engine's existing hose before ordering.

Replaces (OEM)

• Mercruiser 32-52481

Frequently Asked Questions

What is the Sierra 18-70930 used for? It is a molded cooling system hose for fresh water or raw water cooling circuits on inboard and sterndrive boat engines, replacing a cracked, collapsed, or hardened original hose.

Does the 18-70930 cross-reference to a Mercruiser part number? Yes, Sierra 18-70930 directly replaces Mercruiser part number 32-52481.

What material is the hose made from? The 18-70930 is built from EPDM tubing with a synthetic knit reinforcement layer, chosen for resistance to heat, ozone, and continuous water exposure.

Is this hose molded or a straight-cut piece I have to bend myself? The 18-70930 is molded to its bend at the factory, so it holds shape and maintains full water flow through the curve rather than kinking like a forced straight hose.

How much does the 18-70930 hose weigh? The Sierra 18-70930 molded hose weighs 0.2 pounds.

What color is the Sierra 18-70930 hose? It is white.

Is the Sierra 18-70930 an OEM-quality part or a generic aftermarket hose? Sierra molded hoses, including the 18-70930, are designed to be OEM quality and correct in fit, form, and function for the application they cross-reference.

How many hoses come in the package? The 18-70930 listing is for one molded hose (unit count of 1).

What is the UPC for the Sierra 18-70930? The UPC for the Sierra 18-70930 molded hose is 808282145972.

Will the 18-70930 fit both fresh water and raw water cooling systems? Yes, the 18-70930 is designed for use in either fresh water or raw water engine cooling systems.