Sierra 18-3214 MerCRuiser Alpha One Gen II D494569 & Above Impeller Kit

The water pump service kit for Alpha One Gen II drives from serial number D494569 and above. An impeller wears from the tips in, especially if the boat runs in sandy water, and the warning you get is noise from the pump and creeping temperature. A kit with the gaskets and seal ring in it is the difference between a two hour job and doing it twice.

• Kit contents: 18-3056 impeller, 18-3122 impeller plate, 18-2564, 18-2565 and 18-2566 gaskets, 18-2944 seal ring, two 18-7420 O-rings
• For Alpha I Gen II, BF70 and BF90 drives, s/n D494569 and above
• Built to meet or exceed OEM requirements

Replace the impeller on a schedule rather than on symptoms. By the time the alarm sounds, the vane tips are usually already somewhere in the cooling passages.