Fixing melted ground wire in harness

In fixing up recently purchased 1987 Bayrunner I noticed the blk 16 gauge groundwire coming out of the harness behind the instrument panel was hanging loose and melted. So it is not connected to anything however everything seems to work fine. The diagram I have shows it should be connected to the fuse block behind the dash. In looking at the ground wire connection on the motor I see that the ground wire there is also somewhat melted (black electrician tape hid this somewhat) however it is still connected to the motor. I see also that there is a black wire running directly from the negative at the battery directly to the fuse block behind the dashboard. So I guess everything is grounded and okay, right?
Just to be safe should i remove the old ground wire from the harness that is still connected to the motor?

Re: Fixing melted ground wire in harness

The thing I would be worried about is what the ground wire did to adjacent wires when it got hot. You can easily run a new seperate ground wire from the engine or battery up to the fuse panel.

You may have a ground up at your fuse panel that is a path through a sender or something similar. It is not good enough to rely on a ground such at that in the case you need to power something that takes a lot of current.

Re: Fixing melted ground wire in harness

Yes I understand what you are saying. However I have found a 12 gauge ground wire has been run directly from the negative on the battery to the ground terminal at the fuse block. It appears this was done to replace the ground that was damaged. I am somewhat concerned as you say about the condition of other wires in the harness. But I have run the motor, 125 HP Force, the power tilt, and all other electrical items numerous times, before I noticed this ground wire, and everything worked fine. Is there any way of testing the other wires in the harness to see if they have been compromised?

Re: Fixing melted ground wire in harness

What I would really pay attention to is the large battery cable running between the negative post on the battery and the engine block. If that cable has corroded cable ends or other damage, current will take the path of least resistance which is any of the other smaller gauge wires which may not, and obviously are not, large enough to carry the current required by the starter. Start with the large ground cable and don't just look at it. Disconnect each end, clean, inspect, and reassemble or replace if necessary. Then replace/repair the other grounds. The ground from the battery to the fuse panel should be 10 gauge in my view but the boat manufacturer would have installed whatever the corresponding red wire is that goes to the positive bus on the fuse panel.

Re: Fixing melted ground wire in harness

Very Good. Thank you both very much for sharing your knowledge and advice. What a great site. I have learned a lot and accomplished a great deal as a result. I bought this poor neglected Bayrunner with 1987 Force 125 HP, replaced water pump, drive shaft seal, drained water from gas tank, brought 2 cylinders back to life, rebuilt carburetors, various wiring. Took it out on sunday and she runs excellent. Hooray!!!!