Sierra 18-3012 Neoprene Impeller, Replaces Mercury 47-22748, for Mercury/Mariner Outboard Motors

The Sierra 18-3012 is a marine neoprene water pump impeller built for Mercury and Mariner outboard motors. The impeller drives raw water through the outboard's cooling system, and its molded neoprene body with 6 flexible fins is formulated to withstand the heat and constant flexing that occur inside a marine water pump housing while circulating water to cool the engine. Neoprene is the standard material for outboard impellers because it holds its shape and seal against the pump housing wall even after repeated dry-start exposure, helping maintain consistent water flow to the powerhead.

Each package includes one impeller, ready to install as a direct replacement during routine water pump maintenance or when an impeller has worn, cracked, or lost fins. Sierra states that every Sierra part meets or exceeds the original equipment part it replaces, giving outboard owners a maintenance part built to the same performance standard as the factory impeller. This impeller is designed specifically for Mercury and Mariner outboard engines and is sold under the Sierra brand, a recognized supplier of marine engine parts.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3012
• Product Type: Impeller
• Material: Neoprene
• Number of Fins: 6
• Color: White
• Compatible Engine Type: 4 Stroke
• Weight: 0.03 pounds
• UPC: 030999237132
• Package Quantity: 1 impeller per package
• Warranty: Limited Warranty
• OEM Cross Reference: 47-22748

Fitment

Designed for Mercury and Mariner outboard motors.

Replaces (OEM)

47-22748

Frequently Asked Questions

What does the Sierra 18-3012 impeller fit? The Sierra 18-3012 is designed for Mercury and Mariner outboard motors.

What OEM part number does the 18-3012 replace? The Sierra 18-3012 replaces Mercury Marine part number 47-22748.

What material is the 18-3012 impeller made from? It is made from neoprene, a flexible rubber compound formulated to hold its shape and seal against the water pump housing under the heat and friction of engine operation.

How many fins does the 18-3012 impeller have? The Sierra 18-3012 has 6 fins.

How many impellers come in one package? One Sierra 18-3012 impeller is included per package.

How much does the 18-3012 impeller weigh? The Sierra 18-3012 weighs 0.03 pounds.

Is the Sierra 18-3012 a genuine OEM part or an aftermarket replacement? The 18-3012 is a Sierra-brand aftermarket impeller manufactured to meet or exceed the performance of the original Mercury 47-22748 equipment part it replaces.

When should this impeller be replaced? The 18-3012 should be installed when a Mercury or Mariner outboard's water pump impeller shows worn, cracked, or missing fins, or as part of routine water pump maintenance.

What color is the Sierra 18-3012 impeller? The Sierra 18-3012 impeller is white.

Does the 18-3012 come with installation hardware like a gasket or housing? The package includes only the impeller itself, with one unit per package.

What is the UPC for the Sierra 18-3012 impeller? The UPC for the Sierra 18-3012 impeller is 030999237132.