Aluminum boat questions - with pics

lakelover · #1 March 26th, 2006, 05:04 PM

I have a 14' aluminum utility boat made around 1971. I have a new motor for it and here's the problem, or maybe not. There is a crack about 6 inches long where the transom meets the bottom of the boat. It was caused by all those years being beached and pushed out on a sandy beach and just gradually wore through. I'm almost 100% sure that's the original weld. I stopped the leak with epoxy putty and it's been completely water-tight for two years now. And none of the rivets leak.

Actually I have a couple questions. Should I worry about the crack weakening the overall transom? The wood has all been replaced with pressure treated wood, and the angle brace and corner braces are otherwise in good shape. Should I have it rewelded or is it OK?

Betwen the red marks:

Overall inside:

Overall outside:

Also, the front seat has seen better days. I want to replace it, probably with pressure treated plywood. Do you think that the way the seat is now is a problem for the overall strength of the boat?

Thanks.

lakelover · #2 March 28th, 2006, 01:07 AM

FLATHEAD · #3 March 28th, 2006, 01:36 AM

I would get it welded. If the new motor is bigger than the old motor the stress of the extra power might break that epoxy lose. That is one spot you dont want water pouring in.

one more cast · #4 March 28th, 2006, 02:27 AM

I agree with Flathead. Get it welded and as far as the seat goes you can grind off the rivits, remove the seat and beat it back into shape, re brace it and rivet it back in. I bought my 12' boat for $5 after a tree fell on it. A big hammer, a block of wood, a handfull of rivits and $40 worth of welding the cracks and I've been using it with a 15 hp motor for years.

cobra 3.0 · #5 March 28th, 2006, 02:41 AM

How many horsepower are you putting on? The crack may indeed fail under the pressure of a stronger motor. However, not to the point of weekening the transom as you suggest. It will just leak.

As mentionned by Flahthead, welding is a much better option.

As for your seat, personally I would put on nice piece of regular plywood(marine is better) on the top of the existing aluminum seat by bolting it on with stainless bolts and nuts(regular bolts will rust to heck in short order. Paint or varnish the plywood to your taste.

...actually having plywood on all your seats makes seating much more comfortable(no hot or cold of the metal). My aluminum boat has stained and varnished plywood that gives it quite a nice appearance.

MrBigStuff · #6 March 28th, 2006, 07:53 AM

Call around to your local welding shops. Tell them you need some Aluminum boat seams welded (Heliarc). You may be surprised how cheaply it can be done right.

I'd be more concerned about that tear in the transom lip than the front seat. That lip is more structural than the front seat. Both are easily repaired however.

lakelover · #7 March 28th, 2006, 08:40 AM

It had a 1969 9.5 on it before and will have a 2004 9.9 now. I like the good seat ideas, that should be pretty straightforward. I'll check into the welding, it sounds like cheap peace of mind.

Cobra, believe me, I know about the aluminum hot-seat!

Thanks you guys.

Texasmark · #8 March 29th, 2006, 03:50 PM

Drag the boat to a welding shop that does aluminum welding. You'd be surprised how good and fast the welder can fix you up and you'll be surprised further at how inexpensive it is for what you get.

BTDT.....18' Starcraft I/O complete restoration.

Mark

Silvertip · #9 March 30th, 2006, 05:28 AM

I agree with welding the transom seam. As for the seat, this boat apparently is constantly in the weather so rather than mounting plywood on top and then refinishing it, or worse, getting splinters in your behind as it ages, remove the current seat as suggested. Straighten it, and attach 5/8 or 3/4 inch marine plywood underneath it or better yet, pop rivet two aluminum angles running side to side under it. It will be good as new and no further maintenance will be required.

cobra 3.0 · #10 March 30th, 2006, 12:42 PM

All you need to do is turn the boat over when it's not in use. That's what I do.

lakelover · #11 March 30th, 2006, 02:23 PM

Quote:

Originally posted by cobra 3.0:

All you need to do is turn the boat over when it's not in use. That's what I do.

I does spend its winters upside down, but July thru September, it sits on the beach. I always put three wood blocks under the back corners & point of the bow to get it off the ground, but I'm not always the last one to use it in the season, so sometimes it's right on the ground.

I'll probably take the easy route and just straighten it best I can and bolt some PT plywood over the top of the seat. It rarely gets used as a seat, only stepped on when pushing out, or kneeled on when dropping anchor.