Sierra International 18-2414 Engine Coupler 18-2414. 7L (s/n 6170297 & Up) (1983-1989) stern drives. It is also designed for use with Mercruiser 180 190 488 and 3.7LX (s/n 6170297 & Up) (1983-1989) stern drives. Includes one engine coupler per package....