Leaking Aluminum boat

[olddawgsrule]

Why did I do an Internet search when it lead me right back here??

I see this has be addressed, but I thought of making it new again and learn some more from you folks.

The thread I read (and posted on) talked mainly of rivets leaking and replacing using aluminum rivets and 5200 marine epoxy.
This works for me and will cure a few of the leaks.

The major one is on the keel and was worn down from rubbing on the rocks.
What to use to rebuild and seal this?

Second one (actually 3rd & 4th ones..) is the seam along the keel.
Whatever was in there before has separated.
Again: What to use to seal this?

I have the boat flipped over now and ready to start the repairs.
The rivets were worn down from the rubbing and should be the easy part to repair.
The other leaks are loose bolts from the transom board (backer) needing to be replaced..(another easy repair).
The seam leaking looks like it dented or lifted just enough to separate the sealant between the body and keel (this one I really could use some advise on..)

 

[Grandad]

The seam leaking looks like it dented or lifted just enough to separate the sealant between the body and keel (this one I really could use some advise on..)

It seems to me that trying to "repair" the sealing material will be a difficult, if not impossible, repair without taking the hull apart. I suspect that any such dramatic repair method might not improve things. I haven't heard any comments about a conflict between Gluvit and the sealant, so I would apply it and hope for the best. Before applying the Gluvit, I'd attempt to tighten/rebuck the rivets in the leaking area to ensure that there will be no further structural movement that could spoil your re-sealing attempt. - Grandad

 

[Grub54891]

In the area where it's raised,I would drill out a couple and apply some sealant on there,use some small bolts and squeeze it together. When the sealant dries remove one bolt,apply sealer,rivit back together one bolt at a time. Hard to tell ya without a pic but just a guess on how I'd go about it.

 

[Watermann]

How about some pics of the effected area so we can see what you're dealing with. My SeaNymph had a worn down thin and cracked keel plate from beaching on concrete by the PO so if the damage is similar I can tell you how and with pics on the repair in my resto thread and it has ZERO leaks.

Clean the area well and wipe with acetone. If cracked drill small holes at each end.
I used Marine Tex to then build up the keel plate doing it in a few layers allowing 24 hours between to allow for set up.
Sanded it smooth and formed it to where it was the same shape, blending into the rest of the keel plate.
I then primed and painted it.
On the inside you clean it well, do the wipe down and coat it with Gluvit.

 

[pckeen]

Can you post some pics of what you are looking at? If you are saying that your Keel has worn through, then you need to patch it. Your choices are having it re-welded, or doing a patch, with a combination of JB Weld, a new aluminum plate, and some rivets. If the seam has separated, then I would begin by replacing the rivets - hopefully that will tighten the whole thing back up.

 

[olddawgsrule]

Here comes some pictures

This one I would consider the main leak!
It seems to have been patched with some sort of epoxy, then again with silicone.

This one the arrow points at a slightly lifted area where the sealant has separated.

Slightly greater separation (lower arrow points at the transom bolt which I figure the 5200 will fix).

Some basic separation along the keel that has been re-sealed with silicone

 

[olddawgsrule]

On the first Picture, the forward patch I believe to be a hole in the keel.
And there's one more forward of that and of the same basic size.

For the seam I was thinking Sikaflex.
It's a pretty amazing product and what the Glazier's use on the jobsite to seal their aluminum frames to almost everything.
Kinda like Silicone on steroids (or everything we wished silicone to be..)
Just don't know if there's something better.

Looking forward to your suggestions!

 

[Condor1970]

If you can't get ahold of the Sika-flex, I have another very good option that I have personally discovered....

LEXEL


It is a pure clear Elastomeric rubber that you can get at Lowe's or Home Depot. It is NOT cheap silicon caulk. It smells like Testor's modeling glue, because it is a hard rubber when cured. It is literally like a glue, that just sticks like crazy, loves the water, and never peels off.

I used it to caulk the seams of my 1965 12ft riveted Foremost aluminum fishing boat, from end to end. It works wonders. It is impervious to salt water, and you can even paint over it when fully cured. It really is the best stuff if you don't want to use that white marine adhesive caulk.

 

[olddawgsrule]

Thank you for the Lexel suggestion. Hadn't heard of it before.
May I ask?
How long has it lasted?
How hard is it to use?
The Sika-flex is tough to work with... very stiff product..

 

[Condor1970]

It lasts for years, without issues. A lot of guys are using it on small aluminum boats now, because it is clear, and not white, which is very visible. It comes in a tube like regular caulk, so you'll need a caulking gun. It is very thick, and sticky, so it takes a good squeeze of the gun to get it out. Make sure all surfaces are thoroughly clean down to the metal for best adhesion. You need to fill the cracks and fillet the edges quickly, because it sets in minutes. Do just 2-3 feet at a time. Also, use lacquer thinner to clean your hands or tools when done.

 

[jigngrub]

Trying to fix leaks on the outside of an aluminum boat with goos and goop will be temporary at best, as you can see the previous attempts failed and so will anything you do if you use the same method.

1. Replace all bad rivets, rebucking an already weakened rivet will be temporary too. The rivet is already weakened and stretched and will stretch and leak again.

2. Clean and prep the inside of the boat and use Gluvit or Coat-it on the leaking seams and old rivets that don't leak. The Gluvit will seep down into the cracks of the seams and prevent/stop any leaks. the Gluvit will be a preventive measure on the older non-leaking rivets.

If you haven't already done a leak test on your boat, turn it back over and put it back on the trailer. Fill it with a few inches of water (watch your trailer tires for signs of overloading with the water weight inside the boat). Let the boat sit for a few minutes and look under the boat for leaking rivets and seam leaks. Mark all leaks.

After all the leaks have been fixed do another leak test as described above to make sure you got them all.

Again, trying to stop leaks on the outside of a boat with sealant and goo doesn't work for long, we've seen these attempts fail a zillion times on this forum. Replace bad rivets with new rivets.

This is an easy way to replace bad rivets:
https://www.youtube.com/watch?v=L0MA...eature=related
It turns the 2 man job of bucking rivets into a one man job.

 

[olddawgsrule]

Thank you Condor! I checked MSDS on Lexel and it's a pretty safe product (I seen much nasty'ers!).
Your description of use sounds just like Sika-flex..
I'm going to buy a tube and test it out on some scrap aluminum I have around here.

 

[olddawgsrule]

Thank you Jigngrub!
I did do the leak test and notice in a few of the photos the arrows marking out where I found the leaks.
Replacing the rivets is going to be the easy part, it's the keel seam and the keel-line holes that concern me.
My boat has sprayed on ballast foam in the interior and would have to be removed to coat the interior.
That's not to mention removing the bench seats to get under them...
I realize that sometimes there is no easy way and it has to be done, but..
It is aluminum, and there has to be a better product out there, then I currently know of, that will bond to aluminum.

I tested Sika-flex on 2 pieces of Poplar (1 1/4" x 1 1/4") approximately 2 feet long, only putting a 1/2 inch spot of it between the pieces, leaving a 1/4" gap.
A goop.
The test was to prove the product would work for what we were about to use it for.
After twice the cure time I separated the boards.
It broke apart the Poplar.
It's primary use to bond between glass and aluminum..

I do believe there must be a product that works as well with aluminum.
To this extent, I am going to buy some Lexel and test it along side the Sika-flex.
I have 1 1/2" x 1 1/2" angle aluminum that I will run the same test on.
If the product separates, I will consider it a failure.
If I can not separate or the aluminum bends, then it will be difficult to say the product doesn't work or is a good alternative.
If the product separates.. then I'm pulling the bench seats, removing the foam, scraping the interior, sanding and cleaning and then coating...

Think you know what I'm hoping for!

 

[jigngrub]

Have you taken core samples of your foam to see if it's saturated? If that water is leaking through the spray on foam I'd say you have saturation/water logging problems to go along with your leaky seams and rivets.

Any leaking boat that has been leaking for a while that has floatation foam will have saturated foam that needs to be removed and replaced with dry foam. Saturated foam isn't buoyant and won't float your boat like it's intended to do, instead it adds many pounds (sometimes hundreds) of water weight to your boat making it sit lower in the water and taking away MPH and performance from your motor.

 

[Watermann]

JnG said it all but I would add to use only 3M 5200 marine sealer/adhesive.

The chines or center keel runner that runs along the bottom of the boat are riveted on so if they have a bulge that's off the bottom don't worry about them, only the rivets go through the hull and can leak.

 

[olddawgsrule]

JignGrub: I was curious about the foam, since I have an older sailboat, that needed just that.
I had hoped that foam was better in recent years, but I understand now the same issue occurs.
I will sample and see.
Thank you!

 

[olddawgsrule]

Watermann: I follow this train of thought right up to the bow curve..
In photo 1 you see the point of the bow curve and the separation of keel line.
Once photobucket catches up, I'll post another picture (worth a thousand words), but I think you know what I mean.

So that separation in the keel is not an issue?

 

[olddawgsrule]

I have setup the test of the Lexel.
Not having read these posts first, I did go ahead and clean the keel-line and seal it.
I had the tube open and just didn't wish to waste it..
Cure time, like Sika-flex, is a week, so update on this test will be later this week.

In research of this Lexel, I've found it to be an interesting product.
In using this product I've found it to be much easier in application than Sika-flex.
Cleanup is as easy as a Citrus based cleaner or Naphtha (since it part of it's base make-up).
My only 'con' to the product, and if you're using clear, is it's so clear it's hard to tell if you missed something.
The product is easier to apply because it's not as stiff (quality chalking gun required).
Opinion on shrinkage awaits the drying (as all do, including Sika-flex).
30 minutes to pass tack time (surface cure) which I like.
Supposedly can be used in wet conditions (of which I have a hard believing it would bond to wet/water logged wood).

For those interested, more to come.

Thank you all for your advise and help.
Oh ya... Probably more of that to come as well!

 

[roscoe]

I've used Lexel, and so far have had great results.
I did not use it on aluminum though.



I think of it kind of as a clear 4200.

Also, for those looking for a slightly cheaper version of 4200 or 5200, Attwood makes some that come in larger tubes as well.

 

[olddawgsrule]

It's that time of year! I pulled her out of storage and started this years prep.

Foam was saturated.. It's gone now.
That was a project...

Water tested and found I still have 2 more leaks..
One easy, replace the rivet
The other is still that keel-line separation..
I thinking of bring her over to a friend that works with aluminum and just get that welded shut..
Short of one of you telling me that's supposed to flex..