Will aluminum boat hulls degrade if they are left in (fresh) water?

[Humminbird Greg]

I was wondering if anyone had any input on whether an aluminum boat hull would degrade (oxidize, corrode, pit, i.e. lose mass/thickness) if left in the water for an extended period of time. The Pro Team 18Dc we have is off being repaired. It seems no one likes the 2 inch crack I put in it... I was just wondering if this is what is to be expected since the boat has been in the water here for almost all of the 5 1/2 years that we have had it.





Best regards,

Operator of one very used 1997 Pro Team 18DC

 

[Marke Cicero]

Greg,



I can't imagine sitting in the water would cause that. Then again, I don't live in Alabama and my boat has never been in the water for 5 1/2 years.



You may want to remove it once in a while to wash / wax it.

How's the PH level in the water? All I can think of is if the water is too acidic there me be some corrosion going on??



This is very interesting. Let us know what you find out. Good luck,



Marke

 

[Rich Stern]

Greg, how are the sacrificial anodes on the motor? If they were shrinking, that would be a telltale sign that you are experiencing galvanic corrosion.



Although corrosion is much more of a problem in saltwater (better conductor of electricity), it can happen in fresh water. If there is electrical current flowing between the metals (boat components, boat and dock, boat and something nearby, etc), the anodes will bite the dust first, then whatever else is handy (including aluminum).



Is your boat plugged into shore power when it's in the water?

 

[Humminbird Greg]

The anodes look in fine condition. I don't know if it would make a difference or not but the trolling motor batteries get charged one to two times a month on an average. I pull the boat usually once a month to wash it, more often if someone is going to use it to "test the new depth sounder", but I've never waxed it. It will usually go right back in the water after washing. The hull is discolored and I've always wondered about what was in the water. I don't know the ph level, as we say around here; we get whatever the people in Atlanta flush our way