Electronics (wiring) Question

[fmoore]

I'm re wiring all the electronics on the boat (not the whole boat) because there were a lot of old wires and stuff in there from previous electronics.

Where the positive lead connects to the fuse block the metal is all rusted and green and corroded and eaten away. You can tell it's not just normal corrosion - there must have been a charge there. It was only where the positive lead connected to the fuse panel and nowhere else. Does anyone know what could have caused that, and more importantly, how to fix it?

I have included a horrible blurry cell phone pic that hopefully will give you a general idea of what I'm talking about.

Thanks

[Russell A. Jost]

Can't tell you what the exact cause is but I can help with the fix. Clean the corrosion with baking soda and old wet tooth brush. Shine the surfaces with 1000 grit paper. Put new crimp on the lead. Go to an electrical supply an get a small tube of no-oz or other electrical corrosion inhibitor that is used for dissimular metals. Coat all contact surfaces with the inhibitor and reconnect. Leave a thin coating on all metal surfaces. This should take care of the problem. Hope this helps.

[Free Spirit]

Sometimes caused because the contact was not solid. There is a battery terminal spray that will protect and seal the connesction after you clean them up.

[JD5652]

That's galvanic corrosion....which is caused by having two dissimilar metals connected together...when you introduce and electrolyte (salt water)....then you get the green corrosion.

Russell's fix is dead on.....

[fmoore]

Thanks for the help so far guys.

That's galvanic corrosion....which is caused by having two dissimilar metals connected together...when you introduce and electrolyte (salt water)....then you get the green corrosion.

Russell's fix is dead on.....

JD5652 - If it is galvanic corrosion, is there a certain reason why it would happen on the post with the positive lead but not the one with the negative? Coincidence?

[JD5652]

Thanks for the help so far guys.

JD5652 - If it is galvanic corrosion, is there a certain reason why it would happen on the post with the positive lead but not the one with the negative? Coincidence?

FM-

No real reason that I can think of....maybe take a look at the lugs used...maybe a slightly different metal/manufacturer. Perhaps the positive side was more exposed to the salt air?? Tough to pin that one down...no matter....the fix is the same.

[fmoore]

Thanks JD. Thanks for the help everyone. Looks like I'm all set with this.

[Proheat]

Russell and JD are right on with this. Also, what happens is that after the corrosion starts you lose a good solid connection and then when your devices are operating, the power draw creates heat and over time is basically expansion and contraction which loosens the connection and will corrode more.
After you repair the connection, I agree with russell- coat the connection with the no-alox or even a silicone based grease.