The Mangrove Months

Before finally passing through the canal into the long-awaited Pacific Ocean, there is one last short stop on land. The very last Panama Canal boat preparation. The worn-out cutlass bearing needs to be replaced again, and above all, the cause must be permanently fixed. Since we have been anchored in Linton Bay for weeks anyway, the decision is clear: Mabul will be hauled ashore at the nearby Panamarina, we will rent a room with air conditioning to keep the mood bearable, and we will do what needs to be done.

Lifting is not only routine for the marina crew; we also know the procedure inside out by now. Everything runs smoothly, and shortly afterwards, Mabul is safely sitting on the huge trailer and getting its belly thoroughly pressure washed. Time for an initial assessment: basically, everything is fine, but my careful repair of the small crack aft at the keel-hull transition has once again failed. At least the original crack has not returned; only some laminate below the old weak spot has come loose. In retrospect, I probably meant well and laminated over the keel joint – which makes little sense given the slight movement that is always present there. This movement simply sheared off the two extremely stiff, thin layers of fiberglass laminate. So it’s not too bad, but still a lot of work: the damaged material has to be removed and rebuilt – including the copper antifouling, of course.

After parking Mabul in the marina’s working area, I meet with mechanic Nelson to ask for advice on why we have a defective cutlass bearing again after such a short time. I aligned the engine almost perfectly in Bocas del Toro and installed a new bearing. That was just under 50 engine hours ago! The shaft was also checked for concentricity and the propeller had already been sent to the manufacturer in England for reconditioning. Not to mention the four brand-new engine mounts… I am absolutely clueless as to what the hell is going on here.

I sketch out our drive system in broad terms: The motor is installed backwards in the boat and connected to a so-called V-drive transmission. It sits directly above the stern tube, while the drive shaft runs below the motor to the V-drive. This means that the drive shaft and crankshaft form a “V” shape – hence the name. The advantage: The design is very compact, and the engine can be placed far aft in the boat, which both improves the center of gravity and creates more space below deck. Nelson takes a quick look at my drawing, hears how I have aligned the engine, and starts to grin.

He quickly and professionally explains what I overlooked: When motoring, the propeller pushes the water aft – and with the same force, the shaft is pushed forward into the boat. In a conventional arrangement, this is not a problem because the force acts directly and straight onto the engine’s crankshaft. With a V-drive, however, the “V” angle causes the engine to be pushed slightly upward on the transmission side. This changes the angle of the drive shaft in the vertical plane, and it is no longer centered exactly in the shaft bearing. This effect is further amplified by the lever length of the shaft. Nelson’s last question: “Is the shaft bearing round or vertically worn out?” – What can I say? Bull’s eye!

The solution couldn’t be simpler: in a V-drive configuration, the engine must be lowered by a few millimeters at the front when stationary so that it is perfectly aligned vertically when in motion due to the forces exerted. Sounds perfectly logical – once it’s been explained. Finally, the cause was found! To make sure we don’t make any mistakes this time, I ask Nelson to make the adjustment. Using my pliers wrench, he loosens the two front screws on the motor mounts and adjusts the height on both sides by two turns downwards. With a thread pitch of 1.5 mm, that’s just 3 mm. The whole operation is completed in half an hour.

The most important task is done – time for a break. We drift along in the calm mangrove canal, the dinghy gently beside us, only the soft lapping of the water around us. We enjoy this peaceful scene for an hour until the sight of our dinghy spoils the mood. Only now do we notice how battered it is: Hypalon layers are starting to separate, the plywood transom is coming away from the tubes, and there is hardly anything left of the rubber coating that Hugo, the dinghy doctor, applied in Guatemala. It still serves its purpose – air in, water out – but we know how quickly that can change. Once the glue starts to give way, it’s a fight against windmills, as we’ve seen all too often with other sailors. So a new thought occurs to us: we need a new dinghy – and we need it before we reach the Pacific, where replacements are expensive, complicated, and hard to come by.

The next day, I devote myself to repairing the old repair on the keel – the actual bottleneck before Mabul can go back into the water. First, I break away the loose epoxy laminate, which unfortunately exposes the bare steel of the keel in some places. This means that several additional layers of primer will be necessary before the rebuild can begin. Then I sand down the remaining laminate below the keel joint. Under no circumstances can I laminate over it again, otherwise the same problem will recur. I simply smooth the laminate above the joint, as it shows no signs of delamination and is still in perfect condition – the old defect with the crack has been permanently repaired. Finally, I immediately apply the first of several coats of anti-corrosion primer below the joint to protect the steel from rust. This completes the work for today; the primer must first dry completely before I can continue.

This time, I am replacing the worn cutlass bearing with a different model. Its brass sleeve is significantly thinner, which means there is more rubber. Since I press the brass sleeve into the P bracket anyway, the lighter design is irrelevant, especially since plastic sleeves are even used in aluminum boats to prevent galvanic corrosion. The extra rubber allows for deeper grooves through which the water flows for lubrication and cooling, which will hopefully extend the service life. Nelson also immediately points to the bearing with more rubber when I show him both versions.

To replace it, the propeller must first be removed from the shaft. Since I’ve done this what feels like ten times before, and this time on land, it’s off in five minutes. This is the only way to drive the shaft bearing aft. But as is often the case, it is so firmly seated in the bracket that I cannot move it without special tools or a hydraulic press without damaging the shaft. So I drive it out from aft to forward – simply with a suitable pipe or an old cutlass bearing, of which there are still a few on board. After a few minutes, the bearing is out of the bracket, but now it is stuck between it and the stern tube. As a final step, I take the angle grinder and grind down the brass sleeve until the bearing slides easily through the bracket aft. Done. Pressing in the new bearing is now routine; after barely ten minutes, it is in place and secured with two set screws. Now just mount the propeller, lubricate it, and you’re done. Now all that remains is to trust and hope that everything fits this time. And if anyone reading this thinks, “Did he remember that too?” – please let me know immediately.

The dinghy search is sobering. Our requirements are clear: new, Hypalon tubes, no larger than the old one at 2.90 meters, solid floor, and as light as possible. The latter two points quickly narrow the selection down to aluminum hulls, as fiberglass models are all significantly heavier. In addition, we are here and not in the US or Europe, where there is a huge selection. If you then factor in the price, you inevitably end up with a single model: a Hypalon dinghy with an aluminum hull, 2.80 meters long, available immediately here in the marina, reasonably priced, and with an integrated tank. Nice, nice – but the big question is: where to put it on long passages? Our old dinghy had a removable floor and could be rolled up and stowed below deck. This left the dinghy davits empty, creating space for the Aries, our wind steering system. We briefly look at the identical model with a length of 2.40 meters, but it quickly becomes clear that it is too small, almost as wide as it is long, and hardly any cheaper. This would only slightly alleviate the space problem, but it would not solve it.

But before we make a decision about purchasing a dinghy, we first need to continue repairing the keel joint. Both the upper and lower surfaces have been prepared. Now it’s time to restore the original shape – flexible enough so that no new cracks appear. The material of choice is epoxy filler: it adheres perfectly to the epoxy-based primer and, of course, to the dry epoxy fiberglass laminate of the hull. It can also be applied thickly enough to achieve a nice shape. Once again, this sounds easier than it is – but after making a huge mess with filler everywhere, including a lot of it on me, I managed to apply enough of it to the right places to be able to sand down the original shape later. The next day, I do just that and seal the result with two coats of liquid epoxy to make the area completely waterproof again. After two days, I applied the copper antifouling. You have to wait that long because Coppercoat uses a water-soluble epoxy that doesn’t like the fumes from “normal” epoxy. By the way: never use acetone or similar products for degreasing if you’re going to apply Coppercoat – otherwise you’ll have exactly the same problem.

After a total of ten days, all work on land is finally complete, and Mabul returns to the water. We leave our room with air conditioning and toilet/kitchen, moor the boat at one of the Panamarina’s waiting buoys, and briefly enjoy the feeling of being back on board. Together with Nelson, we want to take a test run to make sure that the engine alignment is now really correct and that the vibrations and associated noises are finally a thing of the past. After that, we want to get through the canal as quickly as possible. I submitted the necessary documents to the canal authority during our stay on land, and they have already been accepted – all that remains is the payment and the few nautical miles to Colón, the entrance to the canal.

Then the test run. The sea has been rough for days, and as soon as we leave the protection of the reef, Mabul is battered by short, steep waves coming straight from the front. Each one slows the boat down mercilessly, sending a splash over the deck – only for us to surf down the wave and pick up speed again the next moment. At first, everything looks good: behind the reef, the drive is silent, not a peep—what a relief! But as soon as the rough up-and-down motion begins, I hear the old noise again. It’s muffled – probably thanks to all the rubber in the new wave bearing – but it’s still there. It’s no longer constant, but only when the boat moves strongly. Nelson checks the alignment in the engine room and assures us that it couldn’t be more perfect.

That’s good to hear, but I’m not satisfied. I expect our drive to run vibration-free under all conditions and at all speeds. As it stands now, it’s only a matter of time before the vibrations wear down the new shaft bearing to the point where it needs to be replaced. After 20 minutes of harsh pounding, I turn around. The waves are now coming exactly from astern, Mabul is rolling gently – and the vibrations are gone. Completely. Pleasant, yes. But that’s exactly how it should always be.

Back at the marina, we discuss our findings with Nelson. He says that the engine alignment is ideal. All other factors are also correct: new, tested shaft, fresh engine bearings, and so on. That leaves only one possible cause—the propeller. And we don’t have just any propeller, but a model in which the three blades can rotate completely independently of each other. This enables excellent reverse driving characteristics and, above all, a self-adjusting pitch. This allows the propeller to achieve maximum efficiency at all speeds, and under sail, the blades adjust themselves to create minimal drag in the water. On paper, it’s an absolute dream propeller.

But here’s the catch: if all three blades are not at exactly the same angle to the central hub, the weight distribution is no longer symmetrical – in other words, the propeller is out of balance. This is precisely what causes vibrations, similar to those caused by a poorly balanced car tire. The centrifugal force generated by the rotation is the only mechanism that forces all three blades into a specific angle. It is probably so strong that small differences in the smoothness of the blades are hardly noticeable. Nevertheless, every time Mabul was ashore, I noticed that the blades did not turn with exactly the same ease. However, stronger influences could override the centrifugal force, as in our case: Mabul climbs up a wave, tilts forward at the crest, and a powerful, vertical stream of water rushes down aft of the keel. That is exactly where the propeller is located. My theory: this stream twists one or more blades so that the balance is lost – and suddenly there are vibrations. That would also explain why they have always been dependent on the swell so far.

So what to do? Just accept that rough seas cause vibrations under the engine, which wear down the shaft bearing at a rapid pace? Not an option for me. The only thing left to do is to test the theory – and what better way to do that than with a cross-check: take down the fancy folding propeller, install a conventional propeller with fixed blades, take a test run, evaluate the results. Sounds simple, but unfortunately we don’t have a fixed propeller on board. And our European 30 mm shaft is a bit of an oddity here. With an inch shaft, we could probably borrow a fixed prop from other sailors without any problems. This is where Nelson comes in again: he has several mechanic friends in Panama City and is confident that he will be able to find a cheap, used, and, above all, suitable propeller for us in a timely manner. For lack of alternatives, we gratefully accept and start our own propeller search in WhatsApp and Facebook groups. So the Panama Canal will have to wait a few more days.

I also noticed a new engine noise on the test run – a quiet rattling sound. Not a good sign. My guess: the bearings of the coolant or seawater pump. Since Nelson is still on board, I ask him to investigate the matter. I open the engine compartment and start the engine. To my surprise, however, Nelson doesn’t go in the direction I expected, but immediately reaches for the air filter at the other end of the engine. He pulls off the intake hose to the turbo, looks at me briefly, and then sticks his finger in where the turbine should be spinning at high speed. But it isn’t. Not at all. Completely seized up – coked-up exhaust residues, even though I deliberately revved the engine repeatedly to burn off the turbo. A problem familiar to many drivers of older turbo diesel engines. Since we have to wait for a new propeller anyway, the turbo overhaul can be done at the same time without any additional delay. The next day, we move Mabul from the buoy to the nearby mangroves to moor there. Shortly afterwards, Nelson removes the turbo. Now we are so close to the mangroves without a working engine that hardly a breath of wind reaches us…

So we have enough time to swim through the mangroves again with the dinghy in tow. We take another close look at the mess and make a decision: we’re buying the new dinghy! If we don’t, we’ll probably regret it in the Pacific. And now we’re stranded again anyway, this time tied up in the mangroves in front of the marina. So we have time to sell the old one and figure out how to properly secure the new one on Mabul. No sooner said than done: the next day, we are the proud owners of an aluminum-hulled dinghy with all the trimmings, and with our existing 10 hp outboard motor, we are now incredibly fast. And the way it plows through the waves… Wow! Why didn’t we do this sooner, we ask each other.

But then came the disappointment: although it is slightly shorter and significantly lighter than the old one, one problem remains – the wind steering system can only be installed when the dinghy is not hanging in the davits. On larger yachts, it is often stored on the foredeck, so I start measuring and make a cross-section template to test all possible and impossible positions. In front of the mast? No chance – the baby stay and cutter stay prevent any kind of installation. But directly behind it, in front of the sprayhood? Unusual, yes. Feasible? It looks that way. Only the life raft has to be removed.

The new plan: the dinghy will have its permanent place at the front. Simply pull it up with a halyard, place it on a bracket that still needs to be built, and you’re done. An initial test works, there’s space. Now we just need to find a new home for the life raft. Many yachts have them far aft on the lifeline. This is difficult for us, because the pushpits are already occupied by two outboard motors and there is no solid lifeline. Well, that can be changed. Besides, if the dinghy is going to be parked at the front in future, I want to get rid of the davits – then the arc will just be an arc. And everything will be nice and clean at the stern, without all the clutter and thousands of lines blocking our view when we’re anchored at sunset. Wonderful.

And then everything happens in quick succession: we decide to have a solid lifeline welded on all around the boat. In addition, we want a holder aft on the new lifeline for the life raft, a welded mount for Starlink, another for our diving tanks, reinforcements on the arc, and a few other small items. No sooner had we made the decision than we found ourselves in the middle of another huge project – even though the Panama Canal boat preparations were almost complete and we were ready to go through the canal.

As always, there are countless smaller projects running alongside, which I won’t list here. But all of this together is once again pushing us both to our absolute limits. The mood on board is tense, compounded by the unbearable heat and tiny mosquitoes that make our lives hell so close to the mangroves. We need a break. A short break without the boat – but only once the welding work is finished, we agree. Except when it comes to planning: Karin wants to book flights to Colombia immediately, but I say we should wait and see – who knows how long it will all take. Especially since Luis, the welder, hasn’t even started yet; only the materials have been ordered. At least Nelson has now overhauled the turbo and the motor for the bow thruster is running again without smoke signals. Both are installed, so Mabul is maneuverable again. That’s something, at least. However, a propeller with fixed blades still seems a long way off – apparently some weirdo in Panama City is buying up everything just to hang the functional parts in people’s living rooms as maritime decorations.

Then it’s time to get started: Luis and his assistant Isaac arrive and immediately begin work on the solid lifeline made of 1-inch V4A stainless steel tubes. Their tool arsenal consists mainly of a welding machine and an angle grinder. The dust and dirt generated in the process is unbelievable – Mabul has rarely suffered as much as she did during these two and a half weeks. Tape measures and right angles seem to be foreign concepts. Who knows what they would have done if we hadn’t been there the whole time. But welding – that’s something Luis can do. That’s why we hired him after I saw his work on other boats. Still, every day we have to remind them not to drop tools on Mabul’s surfaces – dents guaranteed! We feel like kindergarten teachers, except that these guys can weld.

Long story short: In the end, we are satisfied with the result, but the road to get there was rocky. They ran out of the inert gas at least three times because they arrived with huge bottles that were almost empty. Isaac was primarily there to replace the defective solenoid valve, and I was the one who used a tape measure and angle to make sure that everything was halfway straight.

In the end, it’s really tight: Karin has already booked the flights, while the work ethic of our duo is noticeably declining – more than once they don’t show up at all or only stay for two or three hours. Instead of the planned five days, they need three weeks. But finally they are done, Mabul is dirtier than ever, and less than 24 hours later our flight leaves. We prepare Mabul rushed and hastily for our absence of several weeks, pack our things, and a little later we are sitting on the plane to Colombia. What could possibly go wrong in the short time she is left alone in the mangroves?

You can find more photos in this gallery.

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