Corrosion around Rivet's: Boat Restoration/Build or Scrap Metal?

[Stimputello]

So I bought an older 1988 SF14 that was used in saltwater and me not knowing any better might have made a purchase that needs to be scrapped in the end. Whole bottom of the boat was sealed with flex seal which should have been a red flag, but here we are. The pitting around the hull seems negligible however there is some pitting/corrosion around the rivets that attach to the ribs of the boat and leave me a bit worried in terms of structural integrity. None of the corrosion seems to have went all the way through, but there is definitely some pitting around area's I don't think there should be. I have all the tools to add/remove old rivets and know how to prep the aluminum with zinc chromate to prevent further corrosion.

What I want to know, is if there are about 20+ or so rivet's with corrosion similar to this, is this fixable or is this something I should just take to the scrap yard? Will have to remove some rivet's with bad corrosion to check for any white powder to fully clean the material. I was thinking a bigger rivet and some G-flex 650 (possibly fiberglass cloth stepped out to reinforce further) would be a possible fix, and worst-case scenario a riveted patch to replace that area; welding seems extremely hard due to the quality of the aluminum. The picture I currently have attached is not mine, but the pitting around rivets looks very similar to what I have going on. I will be adding more pictures once I get to the storage unit to provide more context. Thank you all for the help!

 

[Stimputello]

So I bought an older 1988 SF14 that was used in saltwater and me not knowing any better might have made a purchase that needs to be scrapped in the end. Whole bottom of the boat was sealed with flex seal which should have been a red flag, but here we are. The pitting around the hull seems negligible however there is some pitting/corrosion around the rivets that attach to the ribs of the boat and leave me a bit worried in terms of structural integrity. None of the corrosion seems to have went all the way through, but there is definitely some pitting around area's I don't think there should be. I have all the tools to add/remove old rivets and know how to prep the aluminum with zinc chromate to prevent further corrosion.

What I want to know, is if there are about 20+ or so rivet's with corrosion similar to this, is this fixable or is this something I should just take to the scrap yard? Will have to remove some rivet's with bad corrosion to check for any white powder to fully clean the material. I was thinking a bigger rivet and some G-flex 650 (possibly fiberglass cloth stepped out to reinforce further) would be a possible fix, and worst-case scenario a riveted patch to replace that area; welding seems extremely hard due to the quality of the aluminum. The picture I currently have attached is not mine, but the pitting around rivets looks very similar to what I have going on. I will be adding more pictures once I get to the storage unit to provide more context. Thank you all for the help!

Excuse the flex seal still coating the boat, haven’t finished stripping it. Here are some more pictures of the pitting around rivets. These are about as bad as they get.

 

[airshot]

That is ugly....not sure permanent repairs can be made if this is prevalent all over the hull. If a small area, a patch could be made to cover it, but if all over the hull.....might not be worth the effort.

 

[Stimputello]

That is ugly....not sure permanent repairs can be made if this is prevalent all over the hull. If a small area, a patch could be made to cover it, but if all over the hull.....might not be worth the effort.

It is most definitely ugly hahaha. I would say that gnarly picture is the worst of it, with much less pitting elsewhere (although there is pitting on most of the hull below the waterline). This boat has an extra wide beam (~63”) which was really enticing for me.

I’m okay with having to touch up epoxy every once in a while, but more-so am worried about the overall structural integrity.

 

[airshot]

I would not use a high up motor nor would I take it out in rough water. Keep the bottom coated with a sealer of some form and you might get away with just some pleasure use.

 

[Wayne Roberts]

Well my friend.............everything mechanically speaking is generally repairable if your willing to put the time into it. The good side is you have the pride of the restoration when it completed. Once you have pressured cleaned the area of concern and wire brushed it down to bare metal wipe it down with mineral spirits, MEK or acetone and let dry followed by Zinc Chromate paint. The Zinc Chromate will stop any further corrosion,,,,,,,,,,(here is Florida I painted my complete boat(s) with green Zinc Chromate for total protection) and you are likely to be fine. Remember that old saying...."I've had a whole lot to worry about in my life and most of it never happened" If there is an issue it will leak first at the weak spot well before any possible failure,

 

[thill]

I've had boats like that before. Maybe it's not vogue, but I wire brushed it clean and used JB Weld to fill the pits. Then sanded and sprayed with zinc. Sanded again, and sprayed with topcoat paint, and it's been years and it still looks the same. Not a single bubble in the paint. (My bro in law's boat)

JB Weld is an old product, but it's a really good product. The trick is getting it really clean first. Wire brush on a variable speed polisher/angle grinder followed by a power washer is what gets it done for me.

What helps is to do a bad area, clean it thoroughly, blow it dry with compressed air, JB weld, sand and then prime it. Then move on to the next area.

Doing it that way, you can see your progress as you go, and it's really encouraging. The more you do, the closer you get, and soon it's done. Plus, if you seal it up as soon as you get it clean, no time to oxidize, and the repair is stronger.

Mind over matter!

 

[mirrocraft16]

I've had a few boats with some pretty bad corrosion from saltwater over the years.
The normal course of action is first to stop the corrosion. What I do is take it over to a buddy's truck shop where they have chemicals used to clean and detail aluminum trailers. Its an acid wash that eats away the corrosion fast.
I then take the hull and wash it really good to be sure all the chemical is off of it. I then wipe the areas to be repaired with rubbing alcohol or acetone. I then use JB Weld to fill the pits and I drill and replace any damaged rivets with original type rivets.
I have an air frame riveting set up from the 50's which works well for setting rivets. If a rivet hole is corroded, I drill it to the next size and use a larger rivet. The OEM rivets on most are 3/16", one size up would be 1/4".
I keep both around here so I never have to worry about ordering them. (I got lucky about 20 years ago and a local company that was building pontoon boats closed up and I bought out all the rivets and metal they left behind from the property owner).

When your done fixing the pitting and any bad rivets, you need to paint it. Epoxy doesn't do well in UV Light, so it needs paint, as suggested above, Zinc Chromate primer is the best solution, followed up by a few good coats of enamel.

I also like to coat the interior of the hull below the water line with Gluvit, which soaks into any potential gaps and seals them permanently. Gluvit is an epoxy product and also needs to be painted over, and for that, on most Starcraft boats I use a speckle paint, or trunk paint that can be gotten at any paint supplier. I like the speckle finish since its not as slippery as shiny enamel and its not reflective, which helps a lot on a hot sunny day.

 

[Stimputello]

Sadly this boat will become scrap, there are too many major problems that will cost too much money/time to fix and will severely alter the project. Upon removal of the keel there was significant precipitate chloride all underneath, there is even a section that was dented and has spread to the hull itself. The hull is quite thin in one area. Many pinholes drilled and has spread to about an inch past where the keel ends. That’s not all…

On the stern at the seam on the bottom of the boat after removal of all flex seal there is aluminum flaking off, rivets missing and more white powder. After cutting/drilling into the aluminum around the bottom seam I found it is filled with more precipitate. Take a look at the attached picture for the inside of that cut, it is barely any aluminum left, flex seal, and quite a lot of galvanic corrosion. I drilled pinholes all the way to the top of the boat and it has spread within 4-6 inches of the top of the boat. It would require too much patching and removal of material than I am willing to put into this ticking time bomb. It seems the previous owner took zero care to it for corrosion protection and more than likely sat in the salt all year round.

Scrapyard is on the schedule this week for the boat and I. I’m a bit bummed that I put some time into this project but am still thankful for the skills I learned along the way haha. New boat is being picked up this weekend and thankfully has seen only freshwater use.

 

[LDUBS]

Sometimes the smart move is to know when to throw in the towel. Looking forward to seeing the new boat!