Need your advice on repairing a crack in aluminum

[OttawaRiver]

I hit a log today and there's a crack between the two piece of aluminum. I can't weld it because there's a gasket near the crack. What should I do?

I never repaired aluminum boats and after doing my research on this forum, I am think of using Gluvit.

Here's some picture of the damage.


BTW, I know, I don't have a good camera

the cracks are 3-4inches long but very thin

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

Can i use gluvit to "coldweld" a piece of aluminum because a small part of the keel seam is gone?

 

[Ober51]

Re: Need your advice on repairing a crack in aluminum

Steel Flex epoxy from the outside, will seal any and all holes. MIght want to first have it professionally welded.

 

[88BLiner]

Re: Need your advice on repairing a crack in aluminum

I read an article in a boating magazine about repairing aluminum hulls with JB Weld. I later tried it on an old boat of mine to fix gouge that happened when I ran up on shore and across a nice big rock. It worked just fine for me and it also sanded pretty easy too.

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

Steel Flex epoxy from the outside, will seal any and all holes. MIght want to first have it professionally welded.

That's the problem... It can't be welded because of the gasket! I went to my boat dealer and told me to not weld it because it will create more problems!

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

I read an article in a boating magazine about repairing aluminum hulls with JB Weld. I later tried it on an old boat of mine to fix gouge that happened when I ran up on shore and across a nice big rock. It worked just fine for me and it also sanded pretty easy too.

I heard that JBweld does work but you have to repatch it every 2-3years because it will crack even when painted. I don't know if it's true.

 

[5150abf]

Re: Need your advice on repairing a crack in aluminum

I had a dime size peice of a lower missing on a 9.9 Evinrude, JB welded it, that was 12 years ago and it is still going strong.

I sold the motor abut 10 years ago but still talk to the guy that bought it, just prep the surface really well adn don't mess with it till it is set.

 

[Yacht Dr.]

Re: Need your advice on repairing a crack in aluminum

Funny..I was gonna say the same thing .. JB it.

I think JB makes a metal weld compound now too..

prep it well.

YD.

 

[ryanmitton]

Re: Need your advice on repairing a crack in aluminum

Hi just so I understand you...do you mean you repaired a missing piece of the skag on a 9.9 using jb? like a chip? or the horizontal fin things? ryan.

I had a dime size peice of a lower missing on a 9.9 Evinrude, JB welded it, that was 12 years ago and it is still going strong.

I sold the motor abut 10 years ago but still talk to the guy that bought it, just prep the surface really well adn don't mess with it till it is set.

 

[5150abf]

Re: Need your advice on repairing a crack in aluminum

No, it was actually the gear case, it is 2 peices on that motor and the peice was out of the bottom part.

Never did take on any water, talked to the guy again last weeek and he said it is still going strong.

 

[Bob_VT]

Re: Need your advice on repairing a crack in aluminum

What is around the crack? Is that some sort of filler? Is the aluminum worn through or worn down in that spot?

Is it on the keel?

Can you properly get to both sides of the crack? Inside the hull and outside?

 

[fishon13]

Re: Need your advice on repairing a crack in aluminum

i had a 12' jon boat when I was a teenager fixed it with JB weld I only had the boat for two years but repair held up fine. However it was a much smaller hole and not a crack. What kind of gasket? welding would be best.

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

What is around the crack? Is that some sort of filler? Is the aluminum worn through or worn down in that spot?

Is it on the keel?

Can you properly get to both sides of the crack? Inside the hull and outside?

Yeah, it was patched with some cheap epoxy by the previous owner (got the boat for a very cheap price, it has a new motor and new trailer) I removed the filler to show the crack. And yes, the crack is located on the keel .

Today, I removed the filler and cleaned the area around the crack with a mixture of water/vinegar and then, polished the aluminum to remove any oxidation. I drilled holes on both side of the crack and I used a sort of mixture of epoxy and zinc (made by the company sodatec, it's called MetalFlex) to patch the crack. The salesman told me that it shouldn't crack (hope it's true)

I will post some pictures tomorrow

 

[Bob_VT]

Re: Need your advice on repairing a crack in aluminum

I have never heard of it? I do know that zinc reacts with aluminum and creates galvanic corrosion......

Marine tex manufactures a gray putty that is an epoxy strong than the white putty...... if you have access from inside the keel I would consider getting some gluvit epoxy and build it up to almost a 1/4" thick.

I am just trying to see it done right the first time.

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

I have never heard of it? I do know that zinc reacts with aluminum and creates galvanic corrosion......

Marine tex manufactures a gray putty that is an epoxy strong than the white putty...... if you have access from inside the keel I would consider getting some gluvit epoxy and build it up to almost a 1/4" thick.

I am just trying to see it done right the first time.

Yes, since the volume of the aluminum is greater than the Zinc on the boat, the Zinc could corrode because of the exchange of electrolytes. However, there's a small amount of zinc (I don't know if it's pure zinc or a zinc alloy... ) and I don't know if it's going to affect the patch

I will see if the patch will e able to stay there for a whole summer!

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

So the epoxy made by the company sodatec is crap! It's already cracked and it's leaking a lot!

 

[Bob_VT]

Re: Need your advice on repairing a crack in aluminum

Sorry to hear it did not work. Live and learn.

Grind or sand it off and get some gluvit. The gluvit has some flex properties and the chance of it cracking is super low.

You may have to build it up in a few layers but it can also be used exterior of the hull too.

 

[cbavier]

Re: Need your advice on repairing a crack in aluminum

Yeah, it was patched with some cheap epoxy by the previous owner (got the boat for a very cheap price, it has a new motor and new trailer) I removed the filler to show the crack. And yes, the crack is located on the keel .

Today, I removed the filler and cleaned the area around the crack with a mixture of water/vinegar and then, polished the aluminum to remove any oxidation. I drilled holes on both side of the crack and I used a sort of mixture of epoxy and zinc (made by the company sodatec, it's called MetalFlex) to patch the crack. The salesman told me that it shouldn't crack (hope it's true)

I will post some pictures tomorrow

You should be alright with it just the way you repaired it. When I was in the Air Force alll cracks were drilled first at the end of the crack to stop the Aluminum from cracking further.

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

Sorry to hear it did not work. Live and learn.

Grind or sand it off and get some gluvit. The gluvit has some flex properties and the chance of it cracking is super low.

You may have to build it up in a few layers but it can also be used exterior of the hull too.

Yeah, ill buy it from iboats since they sell it for a cheap price

You should be alright with it just the way you repaired it. When I was in the Air Force alll cracks were drilled first at the end of the crack to stop the Aluminum from cracking further.

HeHe, my friend (a amateur pilot) told me to do so!

 

[OttawaRiver]

Re: Need your advice on repairing a crack in aluminum

I found this on this forum
http://forums.iboats.com/showthread.php?t=300845

I don't understand the part with the keel doubler and the 3M 5200. Did he use the 3M 5200 to "glue" a piece of keel over the original one?