You see them at just about every boat show. Sometimes it's a six-metre fishing boat, sometimes it's a luxury cruiser with a six-figure price tag. But there are always a few boats with something terrifying lurking under a hidden access hatch in the stern: a "bilge pump" that would barely suffice for aquarium duty in my wife's Red Oscar tank. Sure, it'll get rid of rain water and the occasional bit of spray that seeps down there, but that's not what a bilge pump is for. Its main function is to keep you afloat if everything goes to pot, and frankly, most pumps just aren't up to the job.

Crawling around an engine bay, trying to reach some deeply buried component with three flex fittings on a socket wrench, is nobody's idea of a good time.

Thankfully, at least a handful of production boat builders have recognized this, and offer reasonably good access to the critical bits of the sterndrive system's prime mover.  Still, it seems there will always be a few that insist you hire a double-jointed 8-year-old with the mechanical skills of a Formula One pit crew just to change a spark plug.