Sierra 18-3040 Impeller, Replaces Yamaha 63V-44352-01-00, Neoprene Water Pump Impeller for Yamaha Outboard Motors

The Sierra 18-3040 is a neoprene water pump impeller built for Yamaha outboard motors. It is the rotating component inside the outboard's water pump housing that draws in raw water and circulates it through the cooling system, so a worn or cracked impeller is a common cause of overheating. This impeller has 6 fins molded from neoprene rubber, a material chosen for its resistance to heat, wear, and the abrasive conditions found inside a marine water pump housing. Each package includes one impeller, ready to install as a standalone replacement or as part of a full water pump service.

The 18-3040 is designed to work with Sierra's own water pump service kits for Yamaha outboards, including the 18-3433 Water Pump Kit without Housing, the 18-3412 Water Pump Kit with Housing, the 18-3475 Water Pump Repair Kit without Housing, and the 18-3479 Water Pump Repair Kit with Housing, giving installers flexibility depending on whether the housing also needs replacement. It directly replaces the Yamaha outboard OEM impeller 63V-44352-01-00, making it a straightforward drop-in swap during routine water pump maintenance or when addressing reduced cooling flow.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3040
• Material: Neoprene
• Color: White
• Number of Fins: 6
• Weight: 0.05 pounds
• Included Components: 1 impeller
• Compatible Water Pump Kits: Sierra 18-3433, 18-3412, 18-3475, 18-3479
• UPC: 808282167431
• OEM Cross Reference: Yamaha 63V-44352-01-00

Fitment

Designed for Yamaha outboard engines.

Replaces (OEM)

• 63V-44352-01-00

Frequently Asked Questions

What does the Sierra 18-3040 impeller fit? The Sierra 18-3040 is designed for Yamaha outboard engines, replacing the water pump impeller as part of routine cooling system maintenance.

Is the Sierra 18-3040 the same as Yamaha part 63V-44352-01-00? Yes, the 18-3040 replaces Yamaha outboard OEM impeller 63V-44352-01-00 and is built to meet or exceed the performance of the original part.

How much does the 18-3040 impeller weigh? This impeller weighs 0.05 pounds, consistent with a compact single water pump impeller.

What material is the Sierra 18-3040 impeller made from? Neoprene rubber is used for the 18-3040, chosen for its resistance to heat and wear inside a marine water pump housing.

How many fins does the Sierra 18-3040 impeller have? The 18-3040 has 6 fins, which drive water circulation through the outboard's cooling system.

What color is the Sierra 18-3040 impeller? It is white, the standard color for this neoprene impeller.

What is included when I order the 18-3040? Each order includes one Sierra 18-3040 impeller; the water pump housing and other service parts are sold separately.

Can I use the 18-3040 with a Sierra water pump kit? Yes, the 18-3040 is compatible with Sierra's 18-3433 and 18-3412 Water Pump Kits and the 18-3475 and 18-3479 Water Pump Repair Kits for Yamaha outboards.

Is the Sierra 18-3040 a genuine Yamaha part or aftermarket? The 18-3040 is a Sierra-manufactured aftermarket impeller that replaces Yamaha OEM part 63V-44352-01-00, built to meet or exceed the original equipment specification.

When should the 18-3040 impeller be replaced? A worn, cracked, or missing-fin impeller reduces cooling water flow and can cause an outboard to overheat, which is when replacing the 18-3040 is recommended.

Does the Sierra 18-3040 require a full water pump housing to install? No, the 18-3040 is the impeller only; it can be installed alone or alongside a housing when used with Sierra's full water pump kits.