-- Last Updated: Mar-02-13 4:38 PM EST --
Shear pins haven't been used in typical outboard motors in a few decades (I think some small, off-brand models still have them). Of course, that brings up a really obvious question, besides the question about why no spares were on board. A shear pin breaks into three pieces when it fails, with the center section being longer than the outer two. If the shear pin is entirely enclosed, as is often the case, you don't even need a spare. You can just rearrange the pieces and the motor is fully functional again. If the ends of the pin are not fully enclosed, you can install the center section on one side, and jam a twig or some such thing, trimmed to have the proper extra length, in from the other side of the shaft to keep it there (once the prop is installed, the twig, or whatever you use, will be prevented from flying out). Sure, the connection between the shaft and the propeller is only half as strong now that just one of the two failure planes is occupied by intact metal, but it'll be fine as long as the prop doesn't strike anything. Had you spent two minutes addressing this simple problem (a little longer for a non-fully-enclosed pin) there'd be no story to tell, and maybe it all would have been forgotten by now.