Aluminum hull, salt water.... Problem?

[jdlough]

I'm considering buying a Princecraft Ventura 190 deckboat, with aluminum hull. I have zero experience with aluminum-hulled boats.

I live on the Nanticoke River, MD, right where it dumps into the Chesapeake Bay, so it's fairly brackish and barnacley.

The salt air has corroded my aluminum storm doors at the condo in Ocean City wherever there is a scratch. I assume the same thing would happen to an aluminum-hulled boat in this brackish river? Would standard bottom paint deal with the problem, if there is one?

Anyone have experience with aluminum and brackish water? Bad idea? Do aluminum boats even have some kind of zinc sacrificial anode to deal with this? (just a guess)

Thanks,
Jim

 

[dave11]

Re: Aluminum hull, salt water.... Problem?

I have my aluminum boat in the Gulf all the time. Just keep your zincs fresh.

You cannot use regular bottom paint on an aluminum hull.

 

[mthieme]

Re: Aluminum hull, salt water.... Problem?

There are lots of aluminum boats surviving on the Bay.
I've owned two jon boats over the years with no issues.
My neighbor has a pontoon boat that is aluminum - there is a zinc on each 'toon.

 

[dave11]

Re: Aluminum hull, salt water.... Problem?

For salt water I would suggest a welded hull over a riveted hull.

 

[tashasdaddy]

Re: Aluminum hull, salt water.... Problem?

zincs,zincs,zincs!!!!

 

[mthieme]

Re: Aluminum hull, salt water.... Problem?

jon boats are riveted....thousands of 'em around here decades old.

 

[dave11]

Re: Aluminum hull, salt water.... Problem?

There is a big difference between a jon boat and what he is considering.

 

[mthieme]

Re: Aluminum hull, salt water.... Problem?

True.
But my point was that this should not be a deterring criterion for his decision.

 

[jdlough]

Re: Aluminum hull, salt water.... Problem?

Ok, still considering this boat.

Thanks for the tip about not using copper bottom paint (Duh... I don't know why I didn't even consider that)

Meanwhile, another dumb question. How and where to attach zincs. The boat is currently freshwater, so no zincs. I have searched, but found no clear info. I'm guessing the zincs would be attached at the bottom of the transom, drilled into the transom. I also assume I would use 4200 or 5200 to seal the holes. To ensure a good zinc-to-aluminum contact, is it enough to just make sure there's no paint between the two? Or is there some kind of 'grounding wire' to connect the zinc to the aluminum?

Further dumb question... I should use stainless screws to attach the zincs to the aluminum hull?

Furtherer dumberer question... Do they make specialized real big zincs for aluminum-hulled boats in brackish water?

I intend to leave the boat docked in brackish water all season. Any guess as to how often I'd have to re-zinc?

Meanwhile, "Leaky", my 40 year old wooden Beall skiff, just tore loose and sank at the pier in the storm. My wife's comment, "We're gonna need a bigger boat." (to be continued in new thread)

Jim

 

[jdlough]

Re: Aluminum hull, salt water.... Problem?

Just had a maybe silly thought. Would a zinc anode on my aluminum storm and sliding doors in Ocean City help the corrosion problem? Ever heard of an anode on a sliding condo door?

 

[mthieme]

Re: Aluminum hull, salt water.... Problem?

The toons I have seen with zincs have been attached at the rear of each pontoon below the waterline.

Gotta pic of the skiff?
What are you gonna do with her?

 

[jdlough]

Re: Aluminum hull, salt water.... Problem?

See my most recent post under 'Boat sank. OB 4 Sale. U (find and) Haul!!!' for the sad story of Leaky.

(Although, it's still dark here. Maybe Leaky will wash up in my yard tomorrow with all her barnacles scrapped off)

RE: attaching zincs to hull. I rethinked it. I guess I should use 4200 instead of 5200 (if this is the correct stuff to use at all), since I'd want to uninstall old zincs and reinstall new ones... Right?

Thanx,
Jim

 

[puget sounder]

Re: Aluminum hull, salt water.... Problem?

To jdlough. If yor going to moor your aluminum vessel of that size in brackish waters the grouper in zink is the perfect solution. Made specifically for this purpose

 

[Willyclay]

Re: Aluminum hull, salt water.... Problem?

Wow, all these years I thought I had the only wife on the planet who recommended getting a bigger boat!

 

[BWR1953]

Re: Aluminum hull, salt water.... Problem?

I used to live in MD and trailered my aluminum Bass Tracker into the brackish waters of the Potomac all the time. No zincs, no bottom paint, no problems.

Did that for years before I finally sold the boat for a fiberblass Winner with a 150hp engine. The salinity levels in those rivers is not like it is in the oceans. It's a much, much lower level.

As long as you're primarily in the river and not headed down to the mouth of the bay, I'd say just use the boat as is. And I can't see you taking such a boat out into the bay proper on any but the calmest days.

-BWR

 

[capt sam]

Re: Aluminum hull, salt water.... Problem?

The water here has probably the highest salinity anywhere, when I get off the boat I'm covered in a powdery salt without having gone in the water.....having said that I wouldn't worry alot about the aluminum, I see alot of rental boats here that are pontoons so I doubt there's much issue.

 

[puget sounder]

Re: Aluminum hull, salt water.... Problem?

Back about the "grouper". If your unfamiliar with them, check em out. there a large fish shaped zink with a long cable and clip attached. You just dangle em over the side into the water tie off the cable to a cleat or something and attach the clip to your outboard, outdrive mount bolts etc. you don't permanantly attach them anywhere. they cost around 50.00. I bought one thinking I could mount the zink portion to my hull but found it's about 7" long far bigger than I'd want to use. And when you have to keep zinks submerged or clean em when you take em out of the water it's tooo easy. The whole idea keeps it simple. And their designed for when you moored. I'll send you mine 1/2 price if you wanna try it.

 

[NSBCraig]

Re: Aluminum hull, salt water.... Problem?

There is bottom paint made for aluminum hulls.

 

[marquette]

Re: Aluminum hull, salt water.... Problem?

do you need a anode on aluminum baots that are trailered and washed off after each trip into salt water?

 

[mdunn]

Re: Aluminum hull, salt water.... Problem?

I have an aluminum 17.5 Smokercraft and live on Puget Sound.
All my zincs are connected to the ouboard which in turn of course is connected to the hull.
I check them during my routine maintenance and change as needed.
I think this is pretty standard and I don't know that anything else is required but would be interested to hear where I may be mistaken.
I don't moore my boat in the sound and rinse off after every use and have seen no problems.