Problem with aluminum on boat

[waynesworld5]

After two years of having my Customweld aluminum boat, I started having this problem (look at picture). I fish in saltwater. I also wash my boat (with saltaway) every time it comes out of the water. I took the boat into a Mechanic. They didn?t see any electrical problems. Does anyone know what these markings are?

 

[tashasdaddy]

Re: Problem with aluminum on boat

how long does the boat stay in the water?

 

[waynesworld5]

Re: Problem with aluminum on boat

Just for a day of fishing. Then I bring it out, and wash it. Its also parked undercover in my garage.

 

[Dunaruna]

Re: Problem with aluminum on boat

Is your boat painted ?(can't tell by the pic). Looks like bad pre paint preparation.

 

[waynesworld5]

Re: Problem with aluminum on boat

No, the boat is not painted. What you are looking at is just aluminum. I think if you double click on the picture you can get a closer look.

 

[Salmonseeker]

Re: Problem with aluminum on boat

My guess would be the aluminum is oxidizing, I think it is common on aluminum boats in saltwater. Do a search on aluminum and oxidation.

 

[Salmonseeker]

Re: Problem with aluminum on boat

I just checked out the Custom Weld website and it says they have a lifetime hull warranty. I would give them a call and ask them if they have experienced this problem. I have had very good responses from boat manufacturers when I called them directly, most are very helpful and have knowledge specific to your boat.

 

[ccarver]

Re: Problem with aluminum on boat

hmmm maby its like crop circles man... lol jk.... but ive never seen somthing like that befor... it almost looks like its scratched.. but its to symentrical to be a scracth... idk

 

[5150abf]

Re: Problem with aluminum on boat

Is there a weld on the inside of the boat where the marks are?

At any rate I would get an anode on the hull some where, that should help.

Corrosion on aluminum isn't like rust on steel, it is more like when copper turns green so it should never go all the way through and remain a surface thing.

 

[Rowroy]

Re: Problem with aluminum on boat

Corrosion on aluminum isn't like rust on steel, it is more like when copper turns green so it should never go all the way through and remain a surface thing.

That's not entirely true. I used to work at a water filtration plant and we had a number of aluminum ladders that all but disentergrated from years of oxidation.

It's a chemical process, thereby "burning up" some of the base material (the aluminum) in the process.

The same thing is true about copper.

 

[waynesworld5]

Re: Problem with aluminum on boat

Thank you everyone. We have talked to Customweld they said it was corrosion. They haven't gaven any advice but to wash it after we bring it out of the saltwater. I seriously wash my boat everytime it comes out of the salt water with saltaway and then I wax it. I look at all the other boats at the boat launch and I have never seen another boat like this. We also have a anode on the boat. The anode is clean. Its not picking up any kind of corrosion. Something is wrong, and I just don't get it.

 

[dave11]

Re: Problem with aluminum on boat

I have an Alumaweld boat I use in salt water. I just wash it with fresh water and a brush, also every time. I have had no problems. Make sure you have the correct type of anode and check your ground.

 

[reelfishin]

Re: Problem with aluminum on boat

It looks to me like you need to look into some sort of anode to prevent galvanic corrosion. I'd also look close at your electrical system for a ground fault of some sort. I would clean and seal those areas once you find the source of the problem. I run a sacrificial anode on all of my aluminum hulls that see salt or brackish water.
None have ever shown any sign of oxidation.

 

[1beanie]

Re: Problem with aluminum on boat

where on the hull are u guys placing the anode for the aluminum boats? any help would be appreciated thanks

 

[j_martin]

Re: Problem with aluminum on boat

That's galvanic corrosion caused by electrical current.

1. Is the anode for sure connected electrically to the hull?

2. Is there any other source of stray voltage, like a depth finder or trolling motor, or voltage on the engine frame? Using the boat hull for ground return for lighting?

It is occurring while it is in the water. If it was local action electrolytic activity, your sacrificial anode should be cheese. Something is wrong in the electrics, or in the anode installation, or both.

hope it helps
John

 

[Ned L]

Re: Problem with aluminum on boat

Galvanic corrosion is the result of two dissimilar metals in an electrolyte (salt water), and is what anodes ('zincs' on other material boats) are for. Stray current corrosion is what is caused by faulty or problematic electrical systems & wiring (this is not helped with anodes). Due to the short periods of time your boat is in the water & your washing it down carefully I might be inclinded to look more toward the electrical issue cause (as has been suggested).
As a thought, do you have a water softener with the water you wash down with(?), I think they can sometimes leave a lot of salts in the final water.

 

[wca_tim]

Re: Problem with aluminum on boat

I read somewhere that saltaway is actually a little basic (as in ph greater than 7). If it is or if the detergent you use is, independent of galvanic corrosion, basic ph will eventually dissolve aluminum.... (as in gone alltogether)...

 

[rubinjames]

Re: Problem with aluminum on boat

Based on what I have read and remember those saltwater flush chemicals are mostly sulfamic acid. If you are generating galvonic cell corrosion where aluminum is dissolving using something like saltaway is not a good idea.