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Sea Savvy - ‘Miracle cures’ in a tube, can and stick

If you’re in a bind or want to save some yard fees, sometimes a quick fix can be your salvation

If you’re in a bind or want to save some yard fees, sometimes a quick fix can be your salvation

When you’re dirtier than dirt and walking down a road in the out islands, you notice when someone approaches and doesn’t head to the other side of the road. It gets better as you realize that he’s at least as dirty as you. The bonding begins in earnest when each of you realizes that the other is holding a rusty, broken piece of engine.

The other guy was probably 25 years older than me, and he knew I needed help. It was his village, not mine, and it’s hard to find parts when you’re a stranger. One glance told him that the part in my hand belonged to an old generator — just like one of his.

“Come on to my shop,” he said. “I think I can fix you up.”

And he did, with one of many used spares that hadn’t started leaking quite yet and probably wouldn’t for at least long enough to get me back to the United States. But as he handed it over — no charge, I should add — he told me what to do next time.

“Come over here and look at this,” he said. It was the head of an old generator, with the valves removed. One of the intake valve seats had a discolored area. “I chipped it about two years ago. I fixed it with JB Weld, and it’s been running almost every day since then. I had to pull the head for something else that broke, but that repair, it’s still good.”

He then showed me various other things he’d fixed over the years, with the same product. Grinning at my amazement, he asked me to come to his boat, an old wooden swayback around 100 feet long, which he’d been fishing for many years.

“I keep hearing about those damn young fools who smuggle drugs from the islands into the States,” he explained. “I can’t believe how stupid they are. All they do is get into trouble. What I do is I go to the States every once in a while and I smuggle stuff back here. You wanna see it?”

I wasn’t so sure.

“No problem mon, no problem. You don’t understand. Come on into the wheelhouse.”

It was actually in the captain’s stateroom behind the wheelhouse. He opened the door and there it was: hundreds of boxes of JB Weld piled all over the deck. “I don’t get into trouble; I can make all the money I want selling it over here; and I can fix almost anything that breaks,” he said.

I don’t believe everything I hear — and I’m not so sure about that valve seat — nor do I believe everything I read on the sides of boxes. But I’ve seen enough miracle cures from cans and tubes to make me a believer that if you have the “right stuff” around, you can fix things today better than ever before. The “fix” may not be the very best fix; nothing beats buying a new replacement or having a good yard perform a perfect repair. Issues of safety and component performance in some cases may result from fixes from a can or tube. But if you’re out in the boondocks, where a lot of us like to boat, and you have to fix it or forget it, something in a can or tube may be your salvation — at least temporarily. Or if you’re like me and simply can’t afford to pay the price of perfection, you may choose to take the chance that the repair may have to be redone later or that the part may not work as well.

Caveats for cans

Adherence to several caveats minimizes the risks, starting with using the material correctly. Read and follow the instructions carefully, and be extremely safety conscious. This includes not using materials inappropriate for the circumstances. Read the fine print. For example, the phrase, “Can be used below the waterline” doesn’t necessarily mean that the product can be applied to surfaces that are under water at the time of the application.

When considering products, look for those manufactured by established companies that provide good customer help and specific written information about why and how their product works. Ask others about their experiences with the product. Trust your common sense in evaluating claims. When in doubt, experiment first on something you don’t mind ruining.

The following examples are fixes from a can or tube that I’ve done or seen others do. Fortunately, I haven’t used every repair product available — I’m working on it, but not too hard — so I’m not saying one is better than the other. These are just some examples of what’s available.

One job said it all

JB Weld has attracted many disciples since it was first marketed in the 1960s. It’s a patented two-part (one black, one white) epoxy resin with filler, mixed one to one. A thorough mixture produces a gray puttylike substance that can be spread with a putty knife or similar tool. The manufacturer says it originally was designed to repair engine blocks and will withstand constant temperatures up to 500 degrees F, and up to 600 degrees F for 10 minutes, will bond to almost any metal (not lead) and many other materials, and has a tensile strength of 3,960 psi. As with most similar products, good surface preparation is important.

I used JB Weld to repair an aluminum combination manifold and raw water/freshwater heat exchanger. The part would have cost around $3,000 to replace. The end cap was bronze, and the combination of salt water and the reaction between the dissimilar metals had severely corroded the aluminum where the cap seated, causing a leak. The experience illustrated several issues to be considered with this type of repair.

I first sanded the aluminum surface down to clean metal and wiped it with acetone, using a lint-free cotton cloth. (Any time you use acetone or similarsubstances, heed well the warnings on the can. Never store toxic material such as acetone or muriatic acid below deck.) I built up the aluminum with multiple layers of JB Weld. After each layer cured, I sanded the new surface to remove any traces of wax or other contaminants, cleaning with acetone before adding another layer. The restored surface wasn’t perfectly even because I faired it by hand, and I’m not very good at fairing. (Actually, I’m fairly bad at fairing.)

I supplemented the unit’s O-ring with Permatex High-Temp RTV Silicone Gasket Maker (Part 26B) to fill any small voids. After applying a bead on both surfaces, I torqued the bolts down until the surfaces were touching but not completely tight. When the sealant had cured I tightened just a little more. This avoided squeezing the Permatex out and left just enough to compress slightly without breaking up after it had cured. The repair has held for more than five years, and I’ve removed the end cap several times, though I replace the Permatex and O-ring each time. When and if the repair goes bad, I’ll simply do it again. I’ve got plenty of JB aboard.

I wouldn’t do this where the repair would be exposed to hot exhaust directly from the block, because of the heat tolerances of the product. And I wouldn’t do this where a failure could suddenly release scalding water because of the safety issues. Also, I would think twice before making this repair on a lube oil heat exchanger because of the potential disastrous consequences of salt water getting into the oil should the repair fail. However, this is a risk I probably would take because of the good experiences I’ve had with JB.

Creeping cracks

Sometimes you need a fix deep down where the sun doesn’t shine. I’m talking, of course, about hairline cracks such as those in decks, cabins and around ports. In years past, these called for cures ranging from dynamite to coal tar.

The boatyard approach is often to remove, replace and reseal wood, ports and stanchions or whatever. But sometimes you get a deck leak, and there’s no boatyard around. And sometimes there are plenty of boatyards around, but you’ve already spent your lottery winnings on your last haulout.

To the rescue comes Capt. Tolley’s Creeping Crack Cure. This is a one-part water-based acrylic polymer penetrating sealant. (For those of us who stay awake at night wondering about these things, a polymer is a chemical compound or mixture of compounds formed by a chemical reaction in which two or more molecules combine to form larger molecules with repeating structural units.) The manufacturer says its low viscosity allows it to penetrate even hairline cracks by capillary action. It sets up to form a rubbery mass as its water evaporates.

Dry cracks on a boat are about as plentiful as ice cubes in a sun spot, but the manufacturer claims that a little dampness in the cracks (they shouldn’t be flooded) can actually help the sealant penetrate, anddoesn’t stop the curing process.

When I first saw Capt. Tolley’s on store shelves, I bought some just because I wanted to tell my friends that I had a cure for creeping cracks. I tried it between hurricanes one fall, around a particularly gushy port over my computer station, and it worked. It doesn’t cure any rot that may be down there, and it may be less effective over time if the crack moves or flexes a lot with the boat, but it does stop the leak for a while. I have to redo the job every few years, but that’s much better than pulling out the port. That’s too much like work.

Yacht rot

Most boats I owned when I was much younger had two things in common: They were wood, and they had rot. When I heard of Git-Rot my heart stood still. Could it really get rid of rot?

I knew I was supposed to replace rotten planks, but every time I did I found another rotten plank. This is all the more reason to replace planking, but as I said, I was young. (Unfortunately, my laziness hasn’t improved with age.) So Git-Rot became an important, if not ideal, component in these boats.

The theory is simple. When you induce epoxy resin into the soft rot and let it cure, you have a hard substance that won’t rot anymore, the rotten wood serving as a filler. In the right circumstances products like this can be very helpful. But there are other considerations.

Rot impregnated with epoxy can be strong stuff. In fact, the manufacturer of Git-Rot says the repair will be just as strong as the original wood. Others disagree. For example, the strength of the repair will depend in part upon the degree and extent of rot, the extent of resin infusion, and the texture of the wood and rot. Also, the repair probably won’t be as flexible as the original wood.

There’s a tendency by some to compare the resin and rot to resin and fiberglass, but the various forms of fiberglass have specific properties not found in rotten wood that provide strength. Also, any untreated border area rot will continue spreading into the good wood, and any residual moisture beyond the infusion of resin will promote rot in the surrounding wood. The manufacturer instructs that you should allow the wood to dry before treating, and suggests drilling small holes to ensure deep penetration of the resin. But wait, there’s more …

You might be interested in a chat with Dr. Rot. The Rot Doctor Inc. is a company that specializes in problems like this. It has a product called CPES that also uses pure resin to soak into and harden rot, but the resin is thinned with a wood-derived solvent mixture. This brings it to about the viscosity of diesel fuel so that it will carry the epoxy more deeply into the rot and wood, then “gas off,” according to the company. The tradeoff is that it may deliver less epoxy to the rot material because the epoxy is diluted. However, The Rot Doctor says that the deeper penetration offsets this.

The company advises that CPES is classified as hazardous material because of its solvent content. You probably won’t find it on the shelves of chandleries, but the company says it is licensed to ship it, and you can order direct. Obviously you should closely follow instructions, heed warnings, and be very careful with this and any such product.

Rust crust

But enough talk of rot — what about rust? We all know the redeeming qualities of various products such as CRC 6-56 and CRC Heavy Duty Corrosion Inhibitor. One of the first things I do with any new outboard is to pull the cowling and spray the engine with the latter. I also spray other parts that will rust, such as the tilt locks and cowling latches. But there are less obvious solutions for rust.

In the early 1980s I mated an electric starting motor and a gear reduction box to a much-loved Plath manual anchor windlass. The motor body had no rust protection. Various sages advised many solutions, ranging from having a special plastic enclosure molded, to not being so stubborn and buying an all-new, ready-made electric windlass. Instead, I went to the hardware store and bought several cans of Rustoleum and sprayed on four coats, after sanding. (They’ve got a billion different colors; you can really have a groovy windlass.) No rust for three years. When a little rust finally did creep through the paint, I sanded it off and sprayed on several more coats in that spot. But wait, there’s more …

The bow of that boat regularly dipped into the very salty waters of the Southwest North Atlantic and Bahamas. As a bonus I found, upon disassembling the motor five years later, that the multiple layers of Rustoleum had thoroughly sealed all the seams, making it watertight. This wasn’t the intended use for the product, but it worked for me.

If you’ve got more than just a spot of rust, you might want to use Git-Rust, which is designed to transform ferrous oxide to the more stable ferrous sulfite, which can then be painted. I wouldn’t rely on this type of repair where load-bearing strength is compromised by the rust, but it can be helpful for surface area problems.

Going down

Moving on from submerged electric motors, we should consider submerging boats and how to stop the process. Suppose you’ve had a moment of temporary indiscretion resulting in a hole beneath the waterline. Worse, you’re out where there isn’t help just around the bend. Your pumps aren’t keeping up, and you’d really rather not sink. You need a good emergency repair until you can get in where you can haul out. There’s salvation in a tube.

Marine-Tex has a new flexible adhesive called FlexSet. The manufacturer says it can be applied while under water and that it works for PVC, ABS plastics, fiberglass, metal, wood, glass, and even Hypalon and Lexan. It says FlexSet can be used with fiberglass tape to bridge over holes, or as reinforcement for repairs. Also, it’s said to be non-sagging, non-shrinking, and permanently flexible. (The heck with my boat, I need something like this for my body.)

It’s a two-part, one-to-one mix, unlike the five-to-one mix for the original and also useful Marine-Tex. Other products marketed for use under water are designed to harden after curing and can be stuffed into breaches as fillers. These include the Epoxy Putty Stick by Star brite and Waterweld by JB Weld. You knead these into a doughy wad and work the mass into the damaged area. These products have a relatively short working time — a few minutes — once you begin the process.

But sometimes the hole is large, and you’ve got to do something quickly. I’ve seen salvage crews temporarily patch boats holed below the waterline using BoatLIFE Life-Calk, scraps of plywood and self-tapping screws. Life-Calk also is said to cure under water and adhere when applied under water to a clean surface. In my experience, the bond isn’t as strong as when applied to a dry surface, but we’re talking about a temporary emergency repair. (Sanding off the bottom paint results in a better seal.)

Salvage crews will thread the screws into the plywood, with the tips just through the surface that will be against the hull. They spread Life-Calk liberally on that side of the plywood, get into the water (if necessary) with the wood, hold it over the hole, and screw it to the hull, tightening until the caulk oozes out around the perimeter. If the hull is wood this is relatively easy, but a fiberglass hull requires considerable muscle, and/or some predrilling into the glass with a hand drill (not electric, please). Thin plywood will contour with moderate hull curvatures. Obviously this usually requires calm water, as well as at least two people who are reasonably strong, healthy and good swimmers.

This type of patch has been used for years with various other materials, but Life-Calk and similar flexible under-water sealants can make it easier. The bond normally isn’t as strong as that of epoxy products such as those previously mentioned, but the screws give strength for the hopefully short time you need the patch. Also, you don’t need to mix Life-Calk, and it has a longer working time. If done well, the patch can keep most if not all of the water out, even while under way at slow speeds. It’s important that the perimeter of the plywood be flush against the hull for sealing purposes, and to avoid having it pulled loose by water pressure when you’re moving. Let the product cure at least overnight. (The instructions say that it’s “tack free” in one to three days).

Do wonders never cease?

I’ve just begun to scratch the surface, and there are cures in a can for that, too. Check out the new Interlux line of boat care products for almost anything you’ll need to keep up appearances.

For deep scratches, there’s Gel Coat Scratch Patch. To help cockpit enclosure zippers live longer, try Snap and Zipper Lubricant. To temporarily patch sails, there’s Sail RIPair Tape. I could go on forever, especially if these products were for humans.

If you grew up like me, you probably learned that nothing good comes easily, and you may have snubbed those pretty cans and tubes in auto parts, hardware and boating stores. But civilization has made a few strides since the days of the forge and anvil. Life is easier, even for those of us messing about with boats. Don’t expect miracles to solve your problems, but don’t overlook an ounce or two of salvation on the shelves.