Mercury / Mercruiser Impeller Kit | Sierra 18-3214 Impeller repair kit for many Mercury outboards & Mercruiser Alpha I Gen II stern drives. Sierra Mercury water pump kit For Mercruiser Alpha I Gen II stern drives from s/n D494569 and above Mercruiser Vazer For same kit with upper housing order P/N 18-3147 Replaces Mercury 47-43026T6, 47-43026T8, 47-43026T11, 47-43026Q06 Replces Mallory 9-48313 Replaces Sierra 18-3213