One of the members here is about embark on their own aluminum boat restoration journey if their old aluminum hull can be saved.

 

So I thought I would show the adventure I went through on my current boat, and one I had to scrap- and most importantly- why.

 

So in this thread will be a step by step photographic journey through it all to maybe provide some ideas that others can use on their own aluminum boat restoration journey. Florida is truly a harsh environment for aluminum and so what I experienced here may not be as bad in other states far from saltwater and the heat that accelerates the corrosion process.

 

In this thread I will show 2 boats. 1 is a 1974 AlumaCraft F7 boat made in Minnesota. The second was another AlumaCraft, and this one was a 1983 T-14XL with a very thin hull. A lesson learned right there! The older F7 had a thicker more substantial hull and build.

 

Both of these boats saw years of saltwater use and abuse. Both had corrosion and other issues I had to deal with.

 

I was able to save the F7, but the T-14XL was not salvageable and had to be scrapped as nothing more than sold for its aluminum weight which basically covered the expenses I already had into it. So I broke even on that one, but regretted having to scrap it. The details will follow...

 

The 1974 F7 that I was able to save I found in a craigslist ad. It was located way down in Jupiter, Florida in some guys backyard next to a saltwater canal. It had not been used in years and when I first saw it, it was just laying out in his backyard and had 6 inches of mud and water and plants growing out of it and had its own complete lively ecosystem inside of it. Like using an old boat for a backyard frog and minnow swamp pond.

 

The man was asking $300 for it. Cheap enough for a cheapskate like me. So I drove down to Jupiter with an empty trailer. But when I saw its condition and broken transom I walked away from it. The man said he had to move and could not take it with him. So he said I get it that it's not worth anything in that condition so please take it. Its free.

 

Now your talking the right price. So what the heck. It took both of us to roll it over and dump most of the contents out backwards into the yard and canal. Hopefully some minnows and frogs survived. And this condition of mud in bottom has led to a problem I still deal with to this day that I will get into later on. For now, I'll just get started showing the boats as found. First up will be 1974 F7 as I found it:

 

 

And the 1983 T-14XL:

 

 

 

 

 

A tale of two boats.....

Great to see these old warriors given a new life!!

Only one of them. The 1983 T-14XL was scrapped. Hull too far gone from saltwater galvanic corrosion.

 

And that is the one I think I will start with because it will be a shorter subject to cover. Get the scrap out of the way first and then onto salvation of the F7. And it was an ordeal.

 

Fortunately for me I am an old shop guy. I worked in the sign business for some years and did quite a bit of metal fabrication which came in handy on the saved F7. Its interesting what the previous owner had done to it which I had to undo as you will see soon.

 

The very first thing I did was strip both hulls down to bare metal as much as was possible. I had to get deep into both hulls to see what was really going on hidden down underneath all that stuff we put into boats.

 

This is T-14XL being stripped down. Do you see that 2 inch pipe laying in the boat? That pipe was an aftermarket installation of a homemade live well that led directly to this boat being scrapped.

 

The previous owner had installed it incorrectly directly into the bottom of the boat. And I say incorrectly because that pipe screwed into the bottom of the hull was never installed straight. So for years it had side angled pressure on it which eventually caused cracks around their 2 inch hole they cut into boat bottom. And this boat began to leak which is why it was pulled from service and discarded.

 

And me, I always like to think I can fix stuff and so I believed I could fix this one. Boy was I ever wrong about that.

 

Image below shows the trough in the back of the boat. I had to remove it to get at that transom, and I was not putting back in there. I wanted all the floor space and had no need of that any more!

 

 

I'll just let the photos do the talkin'

 

Look at all the holes in the transom! And that is just half of it.

 

 

 

This is going to be a great series of posts. Thank you FFF!

Thanks! I hope some of you will enjoy this one.

 

Just look at all that hull corroding salt hidden behind the wood in transom! Some of it was 1/4" thick! Welcome to Florida huh?

 

Wet salt 24 hours a day 7 days a week and NEVER drying out hidden in there! Constantly at work corroding hull every second!

 

 

 

 

And the 2" hole from bottom of boat with a couple bad rivets removed for replacements.

 

 

And the inside bottom of the boat in middle at keel where saltwater collected over many years:

 

 

 

Found this under one of the transom knee braces:

 

 

Salt caked onto transom wood. All this salt was nearly 1/4" thick and hidden sandwiched between transom wood and aluminum hull turning transom into swiss cheese.

 

 

Now that I was finally getting back down to just the hull and uncovering all of its secrets, I began to try and clean up the corrosion:

 

 

 

 

 

 

 

You can barely see the circular crack in hull at edges of the nut holding this 2" pipe in the hull. (At bottom of image)

 

 

 

This next image is corrosion all along bottom of the boat where it sat on salty pressure treated lumber for boat bunks. Huge mistake right here! I mentioned this another thread and people keep posting images of redoing their bunks with pressure treated wood right here on the forum!

 

Who knows maybe this ONLY happens in Florida?

 

 

And can you believe I was still in save the boat mode and even went to Alro metals just blocks from my house and bought a new transom plate of 1/4" same grade aluminum and had to hand draw and hand cut out a new transom in both metal and plastic. I was not going to reinstall back into this boat any more wood!

 

This shows the inside plastic piece I purchased to replace the old wood. Much stronger plastic. I think I bumped it up to maybe 1" thick too.

 

 

All hand cut. And in bottom of following image you can see the bags of all aluminum hardware I was using to install these two pieces with. I had to special order the hardware. Not available locally.

 

In these images all I was doing was fitting the new pieces to the transom. This is NOT the install which never happened. I had to scrap these hand cut pieces and find other uses for them.

 

When I would install these pieces I used a special permanent adhesive on both sides of hull before installing. Once on, they are never coming off. Sealed up tight. The F7 I use now was done similar to this but without the internal plastic piece. Just 2 pieces of metal for that boat.

 

The custom cutting was not finished here in these images. I fitted them to mark what else needed to be cut off of them before final installation.

 

Also note I was lowering the top rail of this transom to fit a short shaft motor that I already had. The original transom height needed a long shaft motor and I was not going there. If I could save this boat it was going in calmer freshwater from then on. So I did not need the taller transom. Custom cut down here.

 

And if you notice how I cut this transom out, I left enough of the higher railing on both sides to accommodate trolling motor mounts there later on if needed.

 

 

The new rear transom plate was cut to meet 3 thrust points on the boat. Both top railing corners, and a special cut attachment on bottom to keel. So when motor thrusts forward, this plate would distribute the force across the three most important points.

 

Doing it this way allowed me to remove both transom knees and gain more floor space in boat. No longer needed with a transom this strong.

 

To finish it up I was going to add a top piece of aluminum. A 3 sided piece custom cut to fit only in the lowered cut out section. I could have put a 60 or 75hp motor on this transom when done and have no issues.

 

From this point going forward I would work to minimize the weight by rounding off the lower corners into curves while making sure all holes in transom were covered over forever.

 

The light weight AlumaCraft was met to be flown into remote lakes on float plane straped to the float brace. 
Being built in Minnesota both boats were not intended for salt water as the galvanic corrosion clearly shows. Circulation air helps to reduce corrosion but nothing can prevent corrosion from dissimilar metals on aluminum.

Lots of work to restore the boats, hats off to you.

Tom

Seeing all that work makes me feel guilty for the 12’ Montgomery Ward’s “Sea King” V hull that’s been sitting untouched in my front yard for the last 20 years. 

21 minutes ago, ElGuapo928 said:

12’ Montgomery Ward’s “Sea King” V hull

Which is most probably a Starcraft - they made most of the aluminum Sea King boats and just slapped the MW label and name on them

 

Just like the F&S Scout canoe sold primarily in F&S and DSG stores is actually a relabeled Sun Dolphin Scout SS.

Yep! And to think all that expense and labor for nothing! All I got for this boat was right at $100 in scrap weight- and I got to watch them demolish the boat right in front of me with a bulldozer smashing it for loading into a truck.

 

Finishing up what brought this boat down is the crack that developed around the 2" hole in bottom of boat previous owner cut out for his live well. The side pressure combined with years of vibrations and the metal fatigue just gave way.

 

 

 

So I did my homework on welders. And I found a man who advertised his special skills on super thin aluminum welding by using a soda can and welding aluminum that thin together. He did nice work. And he was also a card carrying certified welder.

 

So I drove the boat to him and left it with him to cover this 2" hole and fix the crack.

 

And do you know after I paid that man and picked my boat up and simply drove it back home that by the time I arrived at home and looked at his weld job it had already cracked wide open again!

 

It was not his weld that failed. It was the hull beside his weld that cracked wide open.

 

I decided right then and there I was NOT driving back to him 35 miles away because even if he fixed it, I could not feel safe in this boat out in the middle of some lake. What if it had split wide open on me out on the water? I had young sons at the time. I did not want to have them in this boat and risk all our lives. So to the scrapyard it went.

 

This is what it looked like when I got home from the welder. I could not blame him. This hull was just too thin, and too corroded into swiss cheese and simply was not going to hold up. I was done. And unfortunately, this boat was done too.

 

 

 

The aluminum used is the older boats was 5052-T3 because it forms easily, but a poor to weld that is why the hull was riveted. 6061-T6 is used on welded hulls and newer hulls may use 7075-T6 a stronger aluminum.

Sorry to read the project was a failure after all the hard work.

Tom

 

Yep. I found that out the hard way. Thanks for your input Tom. Much appreciated.

 

Now for the boat I was able to save... The 1974 F7.

 

As noted above, this boat was found in a backyard in Jupiter, Florida. I got it for free and hauled it back to Orlando area to begin work on it at home.

 

The previous owner had turned it into a duck blind hunting boat and they put a 60hp motor on it which was more than 3 times the rated horse power for this boat.

 

 

My first job was stripping the hull down and removing all the bench seats and flipping it over against my fence to begin scraping off super hard barnacles.

 

This is not going to be grandpa's old row boat any longer!

 

 

 

Stripping out the insides

 

 

Now to inspect the transom work previous owner did to this boat to try and accommodate the 60hp motor. They had welded transom thrust bars in each rear corner to help the transom handle and transfer all that horse power to the top railing on both sides.

 

Their welded in new additions were a knee buster and took up floor space in this boat, and some of their welds had cracked because of the excessive horse power they used was just too much for this old boat. So I had to cut all of that out.

 

 

 

 

 

 

 

These welds were busted and cracked to pieces by the horse power.

 

 

Cracked metal everywhere in this transom!

 

 

 

 

Starting to get somewhere now... plenty of saltwater corrosion under the transom knee is what I think they call it. Don't recall.

 

 

 

All that horse power had begun to detach this transom knee from the keel. And this was the worst of the corrosion to be found on this boat right here hidden underneath. So out it comes- for now.

 

 

And now back to regular old F7 transom... also notice that I cut out the top piece across the transom. I had other ideas going back here...

 

 

 

I think that's gonna take more work than my F-9 did....I'll be following this closely to see how you do.

 

Before

 

After

Some cool old boats there MN Fisher! Hope you get them all fixed up!

 

I could not save the original decal.

 

 

I used cardboard to make a starter template of the back of the transom so I could transfer the pattern onto a piece of white cardboard for fine tuning adjustments and then transfer completed shaved down pattern onto a 1/4" thick aluminum plate I custom cut out for this old boat.

 

 

I began to trim it down to minimal metal to reduce weight while still maintaining structural integrity and strength where needed.

 

 

I began fitting it to the boat and adjusting it little by little as well as having to hammer it into curved shape to fit the boat better.

 

 

 

See how the flat new plate sticks out from boat? Needs a bigger hammer! I had to hammer wrap this plate around the curves of the boat.

 

 

And to keep the boat legal, I had to cut out a small window so police and tag agency could easily view the original VIN serial number stamped into this hull.

 

 

Its starting to fit into place now...

 

 

Just a little bit more hammering away at it needed...

 

 

And the keel attach point. I am trying to make this new transom plate catch all 3 critical thrust points.

 

 

All installed now. Hammered into place and sealed onto the hull permanently using some 3M marine adhesive. Now the prep work on cleaning hull back to clean metal preparing it for $400 worth of finish coatings inside and out. A buddy of mine named Jeff is helping out today.

 

1 minute ago, FloridaFishinFool said:

I could not save the original decal.

There's places on Evil-Bay that sell replicas of the original stickers....mine was fairly well torn up, so I replaced it.

I did find a decal, but not the same one as original. I figured as long as it said AlumaCraft I was good to go.

 

For some reason I cannot locate the images of the front deck construction but I have enough from then and now to show what I did there. Its now 12 years old and not a single issue with the hull or transom.

 

It was a lot of work taking hull back to clean bare metal and eliminating any corrosion where found.

 

 

 

Once cleaned back to shiny clean metal I found out that I did not need an etching primer. So I was told I could get away with now using the number one best aluminum primer ever made call Aluthane. It is marketed under different names, but I went straight to the manufacturer for it.

 

https://epoxyproducts.com/aluthane.html

 

"Our moisture cured urethane (MCU) aluminum filled paint (ALUTHANE) has lots of applications. These include bridges, tanks, docks, and even wood decking around homes. It is an excellent sealer and an attractive silvery interior and exterior coating. MCU coatings are often used when 'by the book' surface preparation cannot be done."

 

"Common applications: bridges, tanks, docks, wood decking, aluminum boat painting, rust prevention on metal structures, protective coating for industrial equipment, concrete sealing."

 

I was told this aluthane should be used directly on the bare metal as a primer. Etching primers are used on corroded aluminum surfaces because the etching component cuts through the oxidation to bond with the metal underneath. I had already taken boat back to bare metal and had no need of an etching primer which was no where near as good a substrate as aluthane is which is why it is a top rated industrial primer sealer.

 

And I must give a word of warning about this stuff that I was told. Whatever it touches. It is NOT coming off. If you get this stuff on your skin you can't wash it off. It kind of has to wear off. It really sticks. And provides an excellent primer for the industrial epoxy coatings to come.

 

I think I used about $125 of aluthane on this old boat.

 

I went online and looked up the top industrial epoxy. At the time a 2 gallon system was $300. I found some guy selling Sherwin Williams top industrial epoxy on craigslist for like $100. So I took a chance and bought it and it worked fine. I got like 3 coats of epoxy inside the boat and 3 coats of epoxy on the outside of the boat. This boat is NOT going to leak!

 

I used the old timers trick of rolling the boat out into the hot midday sun and heating it up super hot. Then applying a warmed up mixture of aluthane also sitting in the sun. I quickly rolled on the first coating on the rivets and seams and rolled boat into garage so hull would begin to cool and contract. This, according to the old timers causes the cooling hull to suck in or draw in the liquid aluthane deeper into the rivets and seams to help seal them up better. I only had to do this on the first coat of aluthane inside and outside.

 

This boat then received 3 coats of epoxy inside and 3 coats outside. Like having 3 hulls in one. One aluminum hull sandwiched in between two plastic epoxy hulls. This boat in 12 years still does not leak not one drop of water.

 

This is the aluthane going on...

 

 

 

 

And now the coats of epoxy. Same epoxy used on industrial pipes at plants, and water towers, etc.

 

I made sure to keep all drain holes in the center ribs open.

 

 

 

 

This image shows the position of the wheels as the boat was first put on the trailer. But down the road I had to move the wheels back to balance it all out better. I had to drill out the trailer frame just so I could move it all back. This was due to heavier motors being used than what it was rated for. Made it kind of bouncy in the front.

 

I go with the standard 150 pound to 300 pound forward weight down on tow hitch. Mine is somewhere around 200 pounds or less. Tows great.

 

And, here I did use 2x4 for the bunks because there is 3 coats of epoxy and aluthane in between corrosive chemicals in the wood that cannot now get through the epoxy to cause any more harm to boat hull. So not an issue here, but if still bare aluminum it would be an issue.

 

Getting there little by little.

 

 

 

The previous owner had used rustable bolts and washers on this old boat's oar lock mounts. The galvanic corrosion had corroded all the way through the hull. This is well above waterline so I could take some shortcuts...

 

 

So I purchased some aluminum washers larger than what you see above to cover that leaky spot.

 

Outside of the boat hull:

 

 

And inside the boat hull & zero issues with it to this day 12 years later.

 

 

On to the front deck.

 

I am no boat expert. And I have no need of compartments and lots of hidden spaces. I wanted this boat to be open and as spacious as possible with minimal obstructions. I want to be able to get to the hull inside this boat from bow to stern when needed. So I was not covering it all up. But I did want a front casting deck for myself. And plenty of room in the back for a second fisherman.

 

When I began looking at the boat hull, and how thin the hull is, and with the simple riveted in bench seat mounts, I knew instantly that if I used an existing bench seat mount for the deck in the rear where heavy men step up and down on it all the time, I KNEW that would begin to wear the rivets and hull and loosen up over time. And besides, I wanted a bigger front deck, and it gave me more storage space underneath.

 

So I came up with an idea to hang the rear of the front casting deck from the upper railing because it was strong enough to withstand constant weight of large men stepping up and down on it.

 

So I went back to Alro metals and bought some custom cut aluminum brackets that I now had to hand hammer into the shape I wanted them to be. I did not want them touching the hull on inside and bent them away from hull so as the hull twists under full power I wanted these hanger brackets to stay clear of the hull. So I pulled them inwards and they are also slightly twisted to make this straight across fit. I then used a heavy gauge aluminum angle piece to handle the weight on those hanger brackets.

 

 

And I began constructing the front deck using all aluminum framing and all aluminum hardware.

 

I can now get away with using the existing bench seat mounts to complete the front deck framing. And I used a scrap piece of the transom 1/4" thick metal to make a custom front seat mount. Here it is now cut to size and being fit into place. I would later on have to shim this piece up to be flush with the PVC expanded foam deck boards I would use.

 

 

That was then. This is now 12 years later with carpet removed. I use velcro to hold carpet peices in place on front deck so I can remove them for cleaning and drying out hanging them over the fence to dry, or replacing as needed. No glue here!

 

You can see a 5 gallon fuel tank in front, and batteries in plastic box behind it.

 

 

I can gain quick access to this area while on water. I had to add support framing to hatch cover to support my weight. No issues in 12 years. Just a little dirty now because I no longer have a garage and have to keep boat in open sided carport. Still covered, but it gets dirty now.

 

 

Taking a look at the transom more closely from photos I took today since I can't find the as built photos...

 

I added an aluminum cross member at top of transom. There are no welds to this transom repair. That top cross member is hinged on each side with a drop in bolt from the top. So when motor thrusts forward, now these hinges can give and move with the thrust if need be.

 

 

 

I've chipped some of the epoxy off the top over the years, but it is still sealing this boat up where it counts.

 

I quickly added an untreated pine board across rear bench seat mount. This was not how I was intending to build it. I was going to cut it in half and do a standoff mounted on floor ribs and make a walkway around rear seat but never got around to it. This has worked fine for 12 years but is not ideal. I left it because backseat boaters like to stand up on it as a small casting deck back there. And it is used as an extra seat so I kept it.

 

 

The old broken transom knee is back in place and still shows the broken off tip from previous owners 60hp motor. I could have left this out and been fine. All aluminum hardware holding it in place. No issues to this day. In fact this was taken just minutes ago. Time to clean the boat for this weekend. My 12 year old son wants to take her out. He was not even born yet when this boat was first restored. My ex was pregnant with him at that time so I had only the 2 year old running around.

 

 

And this is the best $200 I ever spent right here. A 1987 like new OMC U.S. Navy Seals MARS motor. How many of these have you seen before? This is one bad a** hombre right here!

 

An old retird navy guy on west coast of Florida had purchased it at navy auction. It had sat on a shelf at Panama City Naval Surface Warfare dept for nearly 30 years unused and untouched. It was new when navy sold it to him. He took it home and messed with it himself and he made a mistake he never figured out which led to him removing it from his boat and standing it in corner of his garage untouched for years. He listed it on craiglist and I drove out to Brooksville Florida to get it.

 

He had purchased a brand new Mercury 40 for his boat and no longer needed this old MARS motor. So I got it dirt cheap because he thought something was bad wrong with it.

 

I took it to my motor mechanic and he fixed her up in no time. What the old navy guy had done was unplug both spark plug coils and when he plugged them back in, he missed a pin hole. So rather than making a good connection, one pin was on outside of the connector and one spark plug was not firing. So when my mechanic removed the spark plugs, only one was black and the other was shiny silver. Unplug coil and replug coil and she fired right up and purrs like a kitten until she needs to roar. And this thing will scoot..

 

This MARS motor was spec'd to be dropped to the bottom of the ocean 400 feet down. And it could be recovered, brought to the surface and had hand operated pumps and drains installed for the navy only to fire it right back up and go. NOT available in commercial motors of same type. I think this one has a steel block and steel pistons and other steel parts for navy only, and some other motors may have aluminum engine blocks and just not built as well as this MARS motor is made.

 

This MARS motor also has some kind of silencer on the front covering carburetor.

 

I removed all the drains, valves and pumps and extra hoses because those were starting to leak and heck I did not need any of it. I was not planning on dropping this thing overboard to 400 feet down! You can take the numbers off its plate and look up the specs online is how I found them.

 

 

 

This next image shows where the navy's valves and hand pump was originally located.

 

I added the tethered kill switch. I think they are required by law these days for commercial motors, but the navy had no use for a tethered kill switch. Try and imagine navy using this motor to land 8 or 10 seals on a beach in iraq and one of them accidentally pulls on it and kills the motor halfway to shore. Yeah not gonna happen. So I added it because I wanted it. I needed it. Had to have it.

 

Oh and get this... its 2025 right? This 1987 MARS motor is still running like a scalded dog on original factory settings. No need to adjust anything other than the idle needle valve you can see peaking out of the silencer at top of image and next to it shows an arrow which way to lean, other way for richer fuel mixture. Other than that. All original settings. No need to change anything in nearly 40 years!

 

 

 

Trolling motor mount is made out of solid aluminum. I tried using wood. Huge mistake when rough 2 foot swells caught me off guard in Lake Harney one time and I tried to make for shallow waters and split the wood mount and nearly lost trolling motor to bottom of lake. Only power wires held onto it fortunately. Now I am not playing around. Solid aluminum now.

 

And that is a 1985 Minn Kota maximizer digital pulse variable speed power supply I use to drive my 12 volt motors. When I go to 24 volt and 36 volt in this boat I have to use other power supplies which are in the works as I write this. I have a 24 volt 80lb thrust and now a 36 volt 110lb thrust for this little 14 foot simple man's bass fishing boat. For free I can't beat it. And a $200 bat out of hell motor!

 

 

 

You know how most people raise their motors over top the transom balanced up there so they do not put too much pressure on the transom when towing the boats? I never had to do that. I can leave my motors in place and go down bumpy roads and this redone transom is strong enough to handle it no problem. I could put two motors on it and still not have an issue.

 

Since I kept that rear bench type of seat, it works for storing tackle boxes and small coolers out of the way.

 

And I have easy access and room under front deck to store all life jackets, paddle, floating boat seat cushion, extra water, canned food, various outdoor supplies for camping, and tools.

 

I am purely a catch and release fisherman so no live well. If I keep fish, they go on ice in cooler in back of boat as needed.

 

The following image shows my second trolling motor mount made of PVC expanded foam. That did not last long. Today its solid aluminum.

 

 

 

She ain't much, she is sure reliable. No issues in 12 years, other than blowing up the yamaha.

 

Apparently this 2007 yammy was built during an 8 year period when Yamaha used an inferior metal alloy that caused corrosion badly in saltwater conditions. I was told Yamaha was sued in federal class action lawsuit over it to. So Yamaha had to change to better engine block materials in the future, but I got screwed on this one.

 

One day she started sputtering and come to find out, this 4 stroke was corroding across the head gasket letting oil get into the water and letting water get into the oil. She was toast. That is when I bought the MARS motor and have been running ever since with no problems.

 

 

Way back up top I mentioned this boat had mud and a living ecosystem in it when I found it. Take a look at an ongoing problem in this old boat. Mud and dirt got way up into the floor ribs and I tried everything short of drilling holes at the top of each one and forcing water down through them to wash them out. Lots of work trying to clean them out but guess what still happens from time to time?

 

I got gremlins! And that about wraps it up for this old boat. This is not grandpa's old row boat any more!

 

My next aluminum boat may be a custom made hull. And I want a thicker hull next time too- and an all weld.

 

So when you hear me talking about corrosion prevention in reels- and boats- this thread shows clear photos of why I have to stay on top of it here in Florida. Speaking of which I am going to spray down that MARS right now.

 

 

I find it amazing that you photographed and documented your projects so thoroughly.  Excellent!