Sierra Water Pump Kit 18-3397, Without Housing, Replaces Yamaha 679-W0078-00-00 and 679-W0078-A0-00

The Sierra 18-3397 Water Pump Kit is a without-housing water pump rebuild kit for Yamaha outboard applications. It is designed to restore proper cooling system operation by replacing the wear components of the water pump assembly rather than the full housing, making it a cost-effective solution when the housing itself is still in good condition. The kit is a complete component set: it includes an impeller (Sierra 18-3088, O.E. 6F5-44352-00-00), an impeller key (Sierra 18-3300), and mounting bolts (Sierra 18-0256), giving installers everything needed to rebuild the pump's wear parts in one purchase.

This kit directly replaces Yamaha O.E. Water pump kits 679-W0078-00-00 and 679-W0078-A0-00, so it is a drop-in match for outboards originally fitted with either of those Yamaha part numbers. Because it omits the housing, it is intended for rebuilds where the existing housing is being reused; buyers who also need a new housing should confirm that separately before ordering.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3397
• Product Name: Water Pump Kit
• Housing Included: No (without housing)
• Category: Yamaha Outboard Water Pumps and Impellers, 2 Stroke
• Weight: 0.45 pounds
• UPC: 030999753632
• Kit Contents: Impeller (18-3088, O.E. 6F5-44352-00-00), Impeller Key (18-3300), Bolts (18-0256)

Fitment

• Yamaha outboard engines originally equipped with water pump kit 679-W0078-00-00 or 679-W0078-A0-00, 2 stroke

Replaces (OEM)

• 679-W0078-00-00
• 679-W0078-A0-00

Frequently Asked Questions

What does the Sierra 18-3397 water pump kit include? The kit includes an impeller (Sierra 18-3088, O.E. Number 6F5-44352-00-00), an impeller key (Sierra 18-3300), and mounting bolts (Sierra 18-0256). It does not include the water pump housing.

Does this kit come with a housing? No, the Sierra 18-3397 is a water pump kit without housing, meaning it supplies the impeller, key, and bolts for a rebuild but not the pump housing itself.

Which Yamaha OEM part numbers does 18-3397 replace? This kit replaces Yamaha water pump kits 679-W0078-00-00 and 679-W0078-A0-00.

How much does the Sierra 18-3397 weigh? The Sierra 18-3397 water pump kit weighs 0.45 pounds.

What is the impeller's OEM number in this kit? The impeller included in kit 18-3397 is Sierra 18-3088, which corresponds to O.E. Number 6F5-44352-00-00.

Is this kit for 2 stroke or 4 stroke Yamaha outboards? The 18-3397 kit is listed under the Yamaha Outboard Water Pumps and Impellers 2 Stroke category.

What is the UPC for the Sierra 18-3397 water pump kit? The UPC for the Sierra 18-3397 water pump kit is 030999753632.

Can I reuse my old water pump housing with this kit? Yes, the 18-3397 kit is designed as a without-housing rebuild kit, so it is intended to be installed with the existing pump housing rather than a new one.

Are the impeller key and bolts included separately or already installed? The impeller key (18-3300) and bolts (18-0256) are supplied as individual components within the 18-3397 kit, ready to be installed during the rebuild.

Is the 18-3397 kit a genuine Sierra part? Yes, 18-3397 is the Sierra manufacturer part number for this water pump kit, sold as a direct replacement for the listed Yamaha OEM kits.