Sierra 18-3450 Water Pump Kit without Housing, Yamaha Outboard, Replaces 63D-44322-00-00 / 68T-W0078-00-00

The Sierra 18-3450 Water Pump Kit without Housing is a complete impeller service kit built for Yamaha outboard engines. It is the same kit as Sierra's 18-3410 Water Pump Kit, but sold without the water pump housing, making it the right choice when your existing housing is still in good condition and only the wear components need replacing.

The kit supplies every part needed to rebuild the water pump's wear side: a Sierra 18-8910 impeller, an 18-3444 insert cup, an 18-3142 impeller plate, an 18-3176 water seal damper, an 18-3294 impeller key, four 18-0256 bolts, and an O-ring. The housing itself is constructed of aluminum. Because cooling pump failure can quickly lead to engine overheating, replacing worn impeller components on a regular service interval helps protect the powerhead.

Sierra 18-3450 is engineered to meet or exceed the original equipment part it replaces and is interchangeable with Yamaha 63D-44322-00-00 and 68T-W0078-00-00. Always confirm your existing part numbers before ordering to ensure a correct fit.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3450
• Product Type: Water Pump Kit without Housing
• Material: Aluminum
• Weight: 0.5 pounds
• UPC: 808282200046
• Fitment: Yamaha outboard engines
• Kit Contents: Impeller, Insert Cup, Impeller Plate, Water Seal Damper, Impeller Key, 4 Bolts, O-Ring
• OEM Cross Reference: Yamaha 63D-44322-00-00, Yamaha 68T-W0078-00-00
• Interchangeable With: Mallory 9-48613

Fitment

• Yamaha outboard engines

Replaces (OEM)

• Yamaha 63D-44322-00-00
• Yamaha 68T-W0078-00-00

Frequently Asked Questions

What is included in the Sierra 18-3450 Water Pump Kit? The kit includes one impeller, one insert cup, one impeller plate, one water seal damper, one impeller key, four bolts, and an O-ring, all sized to rebuild the wear side of a Yamaha outboard water pump.

Does the 18-3450 kit come with a water pump housing? No, this kit does not include the housing. Sierra 18-3450 is the same contents as Sierra's 18-3410 kit but sold without the housing, for engines where the existing housing is still serviceable.

What Yamaha OEM part numbers does Sierra 18-3450 replace? Sierra 18-3450 replaces Yamaha 63D-44322-00-00 and Yamaha 68T-W0078-00-00.

Is Sierra 18-3450 interchangeable with any other aftermarket part numbers? Yes, Sierra 18-3450 is interchangeable with Mallory 9-48613.

What engines does the Sierra 18-3450 kit fit? This kit is designed for use with Yamaha outboard engines; check your existing part numbers against 63D-44322-00-00 or 68T-W0078-00-00 to confirm a match before ordering.

What material is the Sierra 18-3450 impeller kit made from? The components in the Sierra 18-3450 kit are made of aluminum.

How much does the Sierra 18-3450 Water Pump Kit weigh? The Sierra 18-3450 Water Pump Kit weighs 0.5 pounds.

Is Sierra 18-3450 a genuine OEM part or an aftermarket replacement? Sierra 18-3450 is an aftermarket replacement kit engineered to meet or exceed the original Yamaha equipment it replaces, including 63D-44322-00-00 and 68T-W0078-00-00.

What is the difference between Sierra 18-3450 and Sierra 18-3410? Sierra 18-3450 contains the same impeller, insert cup, impeller plate, water seal damper, impeller key, bolts, and O-ring as Sierra 18-3410, but 18-3450 is sold without the water pump housing.

Does the 18-3450 kit include the bolts needed for installation? Yes, four Sierra 18-0256 bolts are included in the 18-3450 Water Pump Kit along with the impeller, insert cup, impeller plate, water seal damper, impeller key, and O-ring.

Does Sierra 18-3450 come with a warranty? Sierra 18-3450 is covered under Sierra's limited warranty as a genuine Sierra product.