Mercury - 125-Amp Fuse Block V12 Electrical System Ceramic Marine Construction 8M0179331. Overview. When you're running a V12 offshore, you expect every part of your engine-big or small-to hold up without hesitation. That kind of confidence doesn't come from guessing or hoping. It comes from knowing the electrical system behind your throttle is protected by components built for the kind of punishment the open water delivers. The Mercury 125-Amp Fuse Block 8M0179331 is one of those quiet, behind-