Re: 1968 OMC i/o sometimes will not shift out of fwd gear. I don't know cause. Help?
could be the switch in the shifter or could be something mechanical in the drive- first step would be to see if voltage remains at the connector just inside the transom.
here's the wiring diagram: http://hhscott.com/evinrude/images/wiring/68_v6_ALL_WIRE.jpg