Mercruiser Alpha One Gen 1 ('86-'90) Water Pump Impeller Kit w/ Housing 18-3320

Water Pump Impeller Kit for Mercruiser Alpha One Gen 1

This Water Pump Impeller Kit with housing (18-3320) is a replacement cooling component for Mercruiser Alpha One Gen 1 sterndrives built from 1986 through 1990.

Overview

This Water Pump Impeller Kit with housing is designed to replace the raw-water pump impeller on Mercruiser Alpha One Gen 1 marine drives. It includes the impeller and housing together so the cooling system can be serviced as a complete set. This Water Pump Impeller Kit fits 1986-1990 Alpha One Gen 1 units and keeps water flowing through the engine at the right pressure.

Built For Performance

• Includes replacement water pump housing and impeller in one kit
• Replaces OEM part number 18-3320
• Fits 1986-1990 Mercruiser Alpha One Gen 1 sterndrive applications
• Designed for raw-water cooling system service
• Supports consistent water flow to prevent engine overheating

Fits These Machines

• for Mercruiser Alpha One Gen 1 (1986-1990)

On-The-Job Use

• Marine maintenance when replacing a worn water pump impeller
• Restoring cooling system pressure after impeller failure
• Servicing Mercruiser Alpha One Gen 1 sterndrive outdrives
• Preventing overheating during long boating sessions

Specs At A Glance

Good To Know

Q: Why does the water pump impeller kit need a housing? A: The housing shapes the water flow around the impeller, which lets the pump maintain pressure and cool the engine effectively. Replacing the housing along with the impeller helps ensure a proper seal and flow.

Q: Can this kit be used on a 1986-1990 Mercruiser Alpha One Gen 1? A: Yes, it is designed for those Alpha One Gen 1 sterndrive models, but always confirm your serial number before ordering.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.