I have been trying to trouble shoot my tach issues and found this wire not connected to anything. Looks like a ground coming from the harness plug. Any ideas and should it be loose? This is a 1979 Johnson 85hp.
With that type of a terminal, it's a ground wire. It is probably not the cause of your tach problems, you need to attach it to the block, look for a stud or bolt near the end of travel to attach it to.