if they are not grounded on the inside and when he docks the boat and plugs it in is where the problem could lie......bad grounding on or the electrical box that he pluged into for his a/c or battery charger..

I was not aware of this option!

Fixx you may be onto something, so ground them to the negative terminal?

Mild, I once you go chrome you can`t go back to black lol

Kris, 10% off is a joke, they should stand behind their work, I`d be seeing DEDPPL if I payed $700 and they gave me that line.

The mounting plates are shot too, so not sure about deflection issues, there is that chalky residue on them (I have no anodes)

My tabs are grounded to my engine blocks

the chalky look is oxidation on the aluminum.

10-4

Especially if using an automotive battery charger.
Lots of people don't understand the difference/risk when using an automotive vs marine unit when used on a boat while in the water.


an electrolysis issue? How do the drives look?

Does the boat stay in the water for long periods of time

everything that touches water and metal should always be grounded together with bonding cable to help it work together to stop galvanic corosion. Then the tabs themselves should have an anode on them or theres no coating that you could put on them that would protect corrosion like that. merc k planes have an anode on them...

Looks like a whole lot of things are going on. I have to agree; with everyones statements, proper grounding, electrolysis, deflection of alum, improper chroming. I would have expected more of the corrosion issues in salt water, if the boat is left in the water, that opens whole lots of possible problems. Docking at a marina, with electrolysis problems, battery charger, no grounding. Usually the alum becomes the sacrificial material, or if in fresh water you can use a magnesium zinc.
Starting over again; with everyones input, should resolve your issue at this point I would not chrome plate, unless using the chrome powder coating. Myself; I prefer; hardcoat anodizing or painting. This seemed like a simple solution; I guess we really need to look closer at issues and not just answer, with the first thing that comes to mind. I myself sometimes take things for granted until actually looking at it, then realizing it wasn't done properly from the start.

Mark

UPDATE:

I had the chroming chemically stripped, then polished, then a top coat of the DuraFortress.
I was thinking of adding an anode and also grounding them.
We`ll see how they hold up but they look like a mirror now.

This durafortress is interesting stuff.........