In the middle of a transom replacement, and need advice. 14' Aluminum boat

I have a 14' Sea Nymph boat and have had a blast with it since this spring. When I bought it, I knew the transom was soft and would need replacing, and my engine doesn't sit high enough. I decided to replace it, and want to do it right.

I decided to strip it bare, repair corrosion with JB Weld, prime with self-etching primer, replace wood with two pieces of 3/4 inch sanded exterior (non-pressure treated) pine plywood laminated together with LockTiteIII and 15 stainless steel screws, also sealing wood with Spar Varnish or Amazing Goop Coat-It, and then painting over everything with something, I am not sure what yet.

First, how does all that sound? Anything I will regret or need to change?

Second, It is taking an awful lot to strip all this old paint to bare clean aluminum, is that necessary? And I am having a lot of trouble getting all the rust and corrosion out of the divets. Please tell me what I can do to get it out. I've tried wire cup brush on a drill, a sander with 100 grit sand paper and paint stripper. I've heard something about vinegar and water... does that work?

Also, I am worried about getting the JB weld smooth enough... I don't want to have to do a lot of sanding because it takes so much aluminum with it!!!

What would you do if this was your boat? I think I may be over complicating it.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

I am really worried about this rust and corrosion, can anyone please tell me how to kill it? Then I will JB weld the holes, then primer with self etching primer... anything I am missing. When do I need to wash with vinegar and water? at all?

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

That Transom looks nasty. Must be a salt water boat.

You might consider finding someone to soda blast it. That would clean off everything and give you a good starting point moving forward.

The vinegar and water wash happens right after you get it all cleaned up. Stops the corrosion. Wire wheel would be my next best suggestion to get it clean.

The JB would work okay to fill the pits. This would also be a great candidate for adding a new outer skin. 3M 5200 troweled on both surfaces and bond the two together. Makes one new very strong transom, just add wood.

jasoutside did this on one of his boats and it worked great.

I know others will add to this soon.

Good luck.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

The cup brush and drill will be most effective but will take a while, a cup brush in a grinder will be quicker.

You're not going to be able to get all of the junk out of the pits, and what you have now is probably good enough. I'd blast it with a pressure washer to remove any loose stuff in the pits and call it good, use a turbo nozzle if you have one. If you don't have a pressure washer just scrub it down with a stiff bristle brush and some Dawn dishwashing detergent.

Skimming with the JB weld is easy, just keep wiping the JB on with a putty knife or bondo spreader. You want to apply enough pressure to force the weld into the pits but keep your knife a a sharp angle to the aluminum so the weld doesn't build up on the top of your metal. Basically you'll spread the weld on and then come right back a swipe it off, this will fill your pits up to the top of the metal with little or no build-up on the top of the metal. If you skim it properly you'll just have a minimum of sanding to do with some 150 grit.

A bit of advice:

Don't try to skim with the JB out in the hot sun, find some shade to do it in and use small amounts... that stuff will set-up pretty quick in this heat. If you do get thick build-up it can be removed easily with a sharp wood chisel before it sets up completely.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

Hey Ron!

Yah, that's a rough looking transom there. I'd agree with osby up there, this one may be well served with a second transom skin. That thru hull on your 4th photo is pretty nasty looking. I'd fear it would continue to crack and such on ya.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

As stated above I would skim the pits with JB weld (Do not use the JB Quick stoff but the regular stuff) or PC-11 (very good stuff).

I have done that before and I actually use 2" plastic tape over the repair so when it is dry (after 24 hours) and you pull the tape off the surface is absolutely smooth!

In your case of the boat........ yes a vinigar wash followed by Zinc Chromate. The ZC is the right stuff and works allot better then the "self etching" primer (at least I have had better permanent repair success with that.

Your wood plans will work and the spar varnish coating will last quite some time. I actually use 4 coats.

Just as a bit of a suggestion......... I also install a stainless steel eye bolt through the transom wood and epoxy over the recessed nut. The eye bolt will provide a place for a cable lock to secure your motor from unsavory people and act as a safety in-case your motor decides to jump off the transom. Hey for a few bucks it is worth the security.

Yup, the corrosion is from something reacting with the old aluminum either salt or some chemical but common in older tin boats.

Consider a piece of 3/8" exterior plywood for the outside of the transom where the motor mounts (you will not be too thick ) and varnish the hell out of that too. Slather on some 5200 and seal it good when it is mounted.

The repair should only last you about 20 years as long as you spend a few minutes and re-varnish it every few years.

Have fun!

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

Can I prime and silicone over jb weld before 24 hours?

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

What are you going to silicone and what kind of silicone are you using?

Read the directions on the tube of silicone, most say Not for use below the water line

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

Hey guys... thanks for all the help. I got a good bit done last weekend and then worked again tonight.

jogngrub, I had considered using silicone on the inside, above the waterline... but didn't end up using it anyway.

Here is where I am... I striped, scrapped, sanded, and wire cup brushed until I couldn't get anymore out of the pits.... then I JB welded. Then I gave it all a vinegar bath, let it dry, wiped down with acetone, and used a self etching primer.

I cut my inside and outside wood, and then used Amazing Goop Coat It on all sides of both pieces of wood, and the inside and outside of the stern piece of aluminum on the boat.

Next, I plan to put it all back together using stainless steel bolts and Fast Cure 5200 red sealant. After it all dries and cures good, I will probably hit it all with spray paint of some kind, is that ok? I am not ready to paint the whole boat, so I'll want to try and blend it with the rest of the boat... is that ok or would I be better to just leave it until I paint the whole boat?

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

Would love to see some pics of the progress.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

Good luck with your project, but I really think you're just prolonging the inevitable "transom replacement"....Again, good luck!

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

Spray paint is ok for short term, be sure to sand your sealed wood pieces before painting so the paint will stick.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

You primed the transom Alum. You should paint it before installing the transom wood, inside and out. It will give a little more protection from corrosion.

Is the Goop Coat it UV tolerant? If not paint it, easier to do before installing IMO.

Then touch up after it is installed.

Re: In the middle of a transom replacement, and need advice. 14' Aluminum boat

I primed all the aluminum and then painted with the goop, I had more than enough for sealing the wood, so added it to the aluminum too. It was made for aluminum boats and is UV tolerant, although I am going to paint it too... it is also sandable and paintable.

I am almost done and then I'll post pics... it's not the prettiest job, but with all the goop and 5200 I used, it will be strong and water tight.

Two quick questions... is 5200 paintable, and how do you get it off your hands!!!!

thanks