Sierra Water Intake Hose 18-3603, Replaces Mercruiser 32-43437, White

The Sierra 18-3603 Water Intake Hose is a white marine-grade replacement hose engineered for boat engine cooling water intake systems. Built to meet or exceed original equipment quality, this hose is designed as a direct replacement for the corresponding Mercruiser water intake hose, giving boat owners and technicians a reliable option when the factory hose has degraded, cracked, or failed. Water intake hoses like this one route raw water from the intake source to the engine's cooling system, so material integrity and a secure fit are essential to prevent leaks, airlock, or overheating.

Constructed from durable plastic material, the Sierra 18-3603 is built to hold up in the demanding marine environment where hoses are exposed to constant moisture, vibration, and temperature changes. It ships as a single unit (1 count) ready for installation. Because water intake hoses are fit-specific, it is important to confirm this part number matches the hose being replaced before ordering.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3603
• Product Name: Water Intake Hose
• Color: White
• Material: Plastic
• Weight: 0.47 pounds
• Unit Count: 1
• UPC: 808282124731
• Category: Mercruiser Hoses

Fitment

Fit specific; confirm part number 18-3603 matches your existing hose before purchasing.

Replaces (OEM)

• Mercruiser 32-43437

Frequently Asked Questions

What is the Sierra 18-3603 Water Intake Hose used for? It routes raw water into the engine's cooling water intake system on boats, replacing the original hose when it cracks, hardens, or fails.

What OEM part number does the 18-3603 replace? The Sierra 18-3603 corresponds to Mercruiser part number 32-43437.

What color is this hose? The Sierra 18-3603 Water Intake Hose is white.

What material is the 18-3603 hose made from? It is made from plastic, chosen for durability in continuous marine water-intake use.

How much does the Sierra 18-3603 weigh? This water intake hose weighs 0.47 pounds.

How many hoses come in the package? The Sierra 18-3603 ships as a single unit, one hose per package.

Is the Sierra 18-3603 a genuine Mercruiser part or an aftermarket replacement? It is a Sierra-brand aftermarket replacement hose built to meet or exceed the quality of the original equipment part it replaces, corresponding to Mercruiser 32-43437.

Will the 18-3603 fit any boat engine? No. This hose is fit specific, so the part number should be checked against the original hose before ordering to ensure proper fit.

What is the UPC for the Sierra 18-3603? The UPC for the Sierra 18-3603 Water Intake Hose is 808282124731.

How is the 18-3603 different from other Sierra water hoses? The 18-3603 is specifically cross-referenced to Mercruiser 32-43437, distinguishing it from other Sierra hose part numbers that replace different Mercruiser hoses.