Mercury - Gear Lube Bottle Assembly Lubrication System 806193A47. Overview. On Alpha and Bravo drives, that little gear-lube bottle tucked in the engine bay does more work than most people realize. When it cracks, yellows, or starts weeping oil, you lose the only easy way to keep an eye on what's happening inside the drive. This replacement bottle fits the newer (2002 and up) MerCruiser sterndrives with standard cooling and drops right into the same spot. It's a simple part, but having a clean,