Leak in Aluminum Seam

[doranj]

I've just discovered that while cruising in my recently restored 1962 14' Starcraft, that water is forced through the seam in the aluminum just under the gunwhale chines. This water comes in under pressure from the spray being deflected by the boat as it moves through the water on plane. The rivets on both sides are tight, but in stripping away the old paint, I believe I also stripped away a rubber sealer that had been applied to the seam at the factory.

So the question is, how do I re-seal the seam. The seam is just below the chine seen in the attached picture, where the black painted bottom meets the unpainted side.

Thanks for your suggestions.

Doran

 

[Huron Angler]

Re: Leak in Aluminum Seam

Wow nice boat

Gluvit is the best product to seal leaky rivets and seams. Is it bare metal on the interior?

If so gluvit will adhere well to the aluminum as it has zinc chromate primer mixed into the epoxy. It remains flexible and is just good stuff. It will creep down into any voids that exist.

It's available here at iboats too.

 

[fshngho]

Re: Leak in Aluminum Seam

Very nice boat Doran. I agree with HA about the Gluvit, however I also know that if you can buy a tube of black urethane that is used to install windshields, that will do the trick. It is primerless and will adhere to aluminum, stays flexible, cures in water, and is paintable. I will not come off anything you get it on (hands, clothing) so be carefull. Takes about 24-36 hrs to cure. I've tried both and like both, depending on circumstances.

 

[Bob_VT]

Re: Leak in Aluminum Seam

Common Starcraft problem...... my old 14 ft'r would leak in that way but not leak out. Tilted the hull to one side applied the gluvit and did the other side the next day.

 

[lakelover]

Re: Leak in Aluminum Seam

If you use the Gluvit, you must paint it if it will be exposed to the sun or it won't last. The UV will make it brittle and deteriorate it, I've had it happen. I had planned to paint it but didn't get to that as quickly as I had hoped and it happened sooner than I expected. Took a couple months.

 

[D.spencer]

Re: Leak in Aluminum Seam

That is sharp looking! another fix, maybee not cheap,would be to use a silicone windshield and glass sealer like mopar p/n 04467708. This may be available thru aftermarket sources like loc-tite or something but this stuff is different from regular silicone sealer in that it is extremely fluid-almost runny and will seep into cracks and small spaces very well on its own. Get a tube and try it before you apply it to get an idea how it spreads. It does not require paint.

 

[coolness]

Re: Leak in Aluminum Seam

That is one sharp Starcraft!!

 

[doranj]

Re: Leak in Aluminum Seam

Thank you all for the suggestions. The leaking seam is in an area that is currently not painted, however painting the seam might help with the sealing. I haven't used Gluvit, but my idea after reading your posts, is to mask along the seam, both above and below, while leaving the seam plus about 1/4 inch above it un-masked to apply the Gluvit. Then, after the Gluvit hardens, paint over it before removing the masking.

Would it be better to brush the Gluvit on, or try to "drip" it into the seam to fill the void?

Doran

 

[Woodonglass]

Re: Leak in Aluminum Seam

Not sure where you live but most woodworking supplies have glue injectors like this...

you could mix small batches of gluvit and inject into the seam. Use acetone to clean the injector. I use them to inject 5 min epoxy into furniture joints for repairs and they work great.

I'm just sayin...

 

[doranj]

Re: Leak in Aluminum Seam

An update on my seam repair:

1. Hoisted one side of the boat to position the seam on about a 45 degree angle.

2. Prepared the seam by brushing with a 4 inch brass wire wheel attached to a vairable speed drill. After cleaning and slightly roughing up the seam with the wire brush, wiped away all residue with laquer thinner.

3. Masked above and below the seam, leaving about 1/2 inch strip exposed. Draped area below the seam with plastic to protect the finish from runs.

4. Mixed Gluvit 5 to 1 as per instructions. Applied to the exposed strip with a small brush, making an effort to first work into the seam, then lay down a heavy coat over the seam. The Gluvit completely filled the "notch" between the aluminum bottom and the aluminum side, with the seam being in the bottom of the notch due to the 45 degree angle of the boat. (continued)

 

[doranj]

Re: Leak in Aluminum Seam

6. Allowed to dry 24 hours and covered with two coats of paint to match the bottom.

7. Repeated the process for the other side.

Had to leave it like that and go to work. I'll give the results of the leak test on the water next week when I get back home. I found the Gluvit easy to mix and work with. The ambient temperature in my work area was around 85 degrees F. It appears that if the Gluvit remains in place without cracking or chipping off, it will be impossible for water to penetrate the seam again. I'll let you know.

 

[bananaboater]

Re: Leak in Aluminum Seam

Definitely a beautiful boat, no lapstrake form in the hull. Would like to see more pics. Thanks.

I would pull off the masking tape ASAP after you get some hardening. When cured that stuff is tough.

 

[doranj]

Re: Leak in Aluminum Seam

I took the StarCraft out today to check the seam repair and the problem is solved - no leak at all. The Gluvit worked, now we'll see how long it will last. Thanks to everyone who posted to help me solve the problem.

I posted the additional pictures for those that asked for more. I appreciate all the nice compliments you have given my boat.

 

[doranj]

Re: Leak in Aluminum Seam

one more

 

[Huron Angler]

Re: Leak in Aluminum Seam

Glad to hear she's dry in the bilge

What kind of material is your exterior transom plate? It looks like it's been rebuilt and looks very nice. Spreads the load out a bit on the stern.

By the way, since you painted it, the Gluvit will last a very long time.

 

[doranj]

Re: Leak in Aluminum Seam

The exterior transom plate is 3/4 inch marine plywood. The original was 3/8 inch and as you noted, much smaller in area. I did it for the reason you mentioned, to spread the load over a greater area. I figured the 30 hp Tohatsu would be heaver and perhaps provide more thrust that the original equipment. Probably unnecessary, but for the little weight it added, I thought it would be better.

It is so nice to have the hull water tight now. I've got a prop question posted on the "Props" forum. I'd be happy to get your take on it if you have time to look. Thank you, Doran