Sierra 18-3070 Impeller, Replaces Yamaha 688-44352-03-00, for Yamaha Outboard Water Pumps

The Sierra 18-3070 is a water pump impeller built for Yamaha outboard engines. The impeller is the rubber component inside the outboard's water pump housing that draws in raw water and circulates it through the engine to keep operating temperatures in check; a worn or cracked impeller is one of the most common causes of overheating in outboard motors. This impeller is designed to replace Yamaha Outboard part number 688-44352-03-00, so it is built to the fit, form, and function of the original equipment part it is intended to replace.

Each package contains one impeller. It pairs with the Sierra 18-3371 Water Pump Kit with Housing and the Sierra 18-3370 Water Pump Repair Kit for a complete water pump service, whether you are doing a full housing replacement or a standard impeller-only rebuild. The impeller is made of aluminum. Because water pump impellers are fit specific to the outboard model and water pump housing they were engineered for, buyers should confirm the part number against their engine's existing impeller or service documentation before ordering to ensure proper fit.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3070
• Item Type: Impeller
• Material: Aluminum
• Weight: 0.04 pounds
• Included Components: Impeller (1 per package)
• OEM Cross Reference: 688-44352-03-00
• Compatible Water Pump Kits: Sierra 18-3371 Water Pump Kit with Housing, Sierra 18-3370 Water Pump Repair Kit
• UPC: 030999315229

Fitment

Designed for use with Yamaha outboard engines. Fit is model specific, so confirm the part number against your engine before ordering.

Replaces (OEM)

• 688-44352-03-00

Frequently Asked Questions

What does the Sierra 18-3070 impeller fit? The Sierra 18-3070 is designed for use with Yamaha outboard engines. Fit is model specific, so confirm this part number against your existing impeller or service documentation before ordering.

What OEM part number does the 18-3070 replace? It replaces Yamaha Outboard part number 688-44352-03-00.

What material is the 18-3070 impeller made of? Aluminum. The impeller's hub is aluminum, with the flexible vanes designed to seal against the water pump housing to move raw water through the engine.

How many impellers come in a package? One Sierra 18-3070 impeller is included per package.

How much does the 18-3070 impeller weigh? It weighs 0.04 pounds.

What other parts do I need for a full water pump service? For a complete water pump rebuild, the 18-3070 impeller pairs with the Sierra 18-3371 Water Pump Kit with Housing or the Sierra 18-3370 Water Pump Repair Kit.

Is the Sierra 18-3070 a genuine Yamaha part or aftermarket? The 18-3070 is a Sierra-brand aftermarket impeller manufactured to replace Yamaha Outboard part number 688-44352-03-00; it is not a Yamaha OEM part.

How do I know if my impeller needs replacing? Signs of a worn impeller in a Yamaha outboard water pump include reduced or no water flow at the telltale (pee hole), engine overheating, and cracked or torn vanes when the old impeller is inspected; the 18-3070 is sized to replace the original 688-44352-03-00 impeller in that pump.

What is included with the Sierra 18-3070? The package includes one impeller only; the water pump housing and gasket kit are sold separately as the Sierra 18-3371 or 18-3370 kits.

Does the 18-3070 come with a warranty? Yes, the Sierra 18-3070 impeller carries a limited warranty.