Sierra 18-8921 Water Pump Impeller for Nissan Tohatsu Outboard Engines

The Sierra 18-8921 is a premium aftermarket water pump impeller designed for Nissan and Tohatsu outboard engines ranging from 9.9 to 20 horsepower. This critical cooling system component ensures proper water circulation through your engine, preventing overheating and maintaining optimal operating temperatures.

Key Features:

• Engineered to meet or exceed OEM specifications for reliable performance
• Compatible with both 2-stroke and 4-stroke Nissan/Tohatsu outboard motors
• 8-blade impeller design for efficient water flow
• Precision-molded construction for durability in harsh marine environments
• Direct replacement for OEM part number 334-65021-0
• Fits 9.9, 15, 18, and 20 HP engines (all models and configurations)

Specifications:

• External Impeller Diameter: 41.11mm (1.62 inches)
• Height: 23.51mm (0.93 inches)
• Internal Shaft Insert Diameter: 13.88mm (0.55 inches)
• Weight: 0.15 lbs

Compatible Models:

• Tohatsu/Nissan 2-Stroke: 9.9D, M9.9D2, 15D2, M15D2, 18E2, M18E2, M16A2, M20A2, M25A2
• Tohatsu/Nissan 4-Stroke: F9.9B2, F15B2, F18B2, F9.9C, F15C, F20C, MFS9.9C, MFS15C, MFS20C

Cross-Reference Numbers:

• Nissan/Tohatsu: 334-65021-0, 334650210, 334650210M
• CEF: 500383
• Mercury: 47-803748

Sierra is a market leader in aftermarket marine engine parts, providing premium-quality replacements for over 6,000 marine components. All Sierra products are backed by their limited lifetime warranty covering defects in workmanship and materials. Regular impeller replacement is essential preventative maintenance—inspect your impeller annually and replace every 2-3 years or whenever damage is observed to ensure reliable engine cooling.