Mercury - Quicksilver 819503A2 Solenoid Kit Mercury 65-125HP Carbureted TwoStroke Outboards 819503A2. Overview. When your starter clicks but your engine doesn't crank, chances are your solenoid's calling it quits. The Mercury 819503A2 Solenoid Kit is the direct OEM replacement that brings your Mercury 65-125HP carbureted TwoStroke outboard back to life with reliable power delivery every time you hit the key.. It's built for the real world - sealed tight against salt, heat, and moisture - and tes