Long Distance Dripless Rubber Booty Call

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No, the title isn't some sort of kinky sex reference, although AnnMarie did fly down here for another conjugal visit (they allow that in Mexico) but the title refers to the new "dripless" mechanical seal she brought with her from Emeryville. The propeller shaft on one of the engines started leaking, and rather than chance having it get worse on our way up the coast, we ordered another. As it turns out, the other engine is starting to drip as well, so we'll need to change that one out pretty soon. What fun, heh?

These are pretty nifty devices, they allow the propeller shaft to exit the hull, and still spin, yet keep the water out. In most older boats there is something called a "stuffing box" (I love that term, it sounds like some sort of Thanksgiving desert) which is a long piece of hose that attaches to the boat, with a brass flange at the other end. The shaft goes through the flange, inside the hose and out the boat. Inside the flange is a "packing gland" (another term whose mental image conjures up something definitely not holiday related) which consists of strips of flax impregnated with some sort of earwax. You unscrew the flange, stuff the flax around the shaft then tighten up on the nut until water stops leaking.

Almost. It actually has to drip a little, constantly, in order for it to work correctly, if you make it too tight then it will overheat when the shaft is spinning. Too lose and water fills your boat. Just right and the water acts as a sort of lubricant and cooling fluid, but means you always have water in your bilge. In actual use, these things are always sort of a problem, and they require constant checking and continual maintenance. Most boat owners dread touching them, it is the moral equivalent of needing to go to a proctologist. It's a problem back there somewhere, you know you should deal with it, but really wish it just healed itself.

There are newer types of synthetic packing material that supposedly work better and eliminate the drip, but the general design is [several hundred years] old technology, and there are newer alternatives. Namely, the "dripless mechanical seal". This system supposedly eliminates the constant drip (thus the name) by eliminating the stuffing box and packing gland entirely.

Instead, a hollow, compressible, rubber bellows is placed around the shaft, one end attached to the boat, and the other terminated with a graphite ring that goes around the shaft. A stainless steel collar then fits tightly over the shaft, it's aft facing surface pressed up against the graphite disk's forward facing surface. Lock nuts hold the collar in place on the shaft, compressing the belows slightly and providing the seal. Because the two disk's surfaces are in compression, no water gets past, yet the shaft can turn without heating up because there is always seawater inside the bellows to keep it cool. In fact, a small tube is run from the rubber bellows up above the waterline (preventing air pockets from forming inside it) to make sure that there is always water cooling the two disks.

Very simple, very clever, and it should last seven to ten years without maintenance or hemorrhoids. What a concept! We'll see just how long and well it works, but it appears to be doing the trick so far. Of course, once we start up the coast will be the real test. Providing the stainless steel collar doesn't slip, it should remain completely dry in the bilge. If it does slip, then water comes gushing in. To that end I've put a couple of pipe clamps around the shaft just behind the collar, as backup, and added a second, completely redundant bilge pump, giving me a total output capacity of about two thousand gallons per hour per engine compartment. Plus another two thousand gallons per hour in each of the separate hull compartments forward of the engines. If I'm taking water on that fast, odds are good the propeller fell out or we were rear ended by a whale.

But first we needed to get the part down here. Now, although there is a brand new DHL shop not ten minutes from here, it hasn't opened yet (it was supposed to have been operational two weeks ago, but this is "manana" land) and according to everyone else getting anything here could take weeks. And more than a hundred dollars. I wanted to get the seal installed before the crew arrived, and get to see Ann again, so she found a cheap, non-stop flight for not much more than what it would have cost to ship it. She ordered the part (it took less than two days to ship it from Europe to Emeryville) and hand carried it down with her. It meant she flew down on the weekend and had to leave for work on Sunday, but it was great to see her again!

Picking her up at the airport I ran into a strange situation. I wasn't sure which public parking was appropriate at the airport, the signs are less than clear, so I pulled up in front of the terminal and asked the cop directing traffic where to go. "Oh, well, you can park over there, or you can leave it here in the red zone if you are only going to be a few minutes...just tip me on your way out." Well, that seemed odd to me, but Ann was due to arrive any second and it wasn't clear how much stuff she would have. I thought about it for a bit, and defaulted to that age old advice: when in Rome, do as the Romanians.

Now if a cop tried that at an airport in the states, he'd lose his job, maybe go to jail. Down here, it is just another day. Several of the other cruisers here have told me about numerous traffic stops that were "resolved" by paying the cop directly, rather than dealing with the ticket. The corruption and bribery is something that I think ultimately needs to change before Mexico will really be able to compete on the global scale, but things are changing fast down here. No doubt even that will fade (it has already improved significantly since the last time I was here) and eventually rule of law will take hold. We all hope so, anyway.

On the way back to the marina, we stopped for a bite to eat. I was pretty tired and very hungry and suffering from low blood sugar. I could barely speak. Ann said "Is there somewhere we can get lunch?" I tried to explain that I knew a place, it was on the way, but that they "...serve meat, and, uh, meat, on potatoes, or you can just get meat." There was a brief pause, then she said, "Oh, can I get meat with my meal?". She laughed and made fun of me the whole way there. But it was really a great place, just a little road side stand, run by "Fidel" (he was quick to point out that there was no relation to Castro) who knows everyone in town. Basically, he serves meat, grilled with potatoes. He sat and chatted with us as we ate, and every other car that drove by honked or waved as they went past. If you are ever in San Jose, check him out, he is on the road that leads to the Marina Los Cabos, just off the traffic circle.

Oh, that is another thing about San Jose. They love, Love, LOVE traffic circles. And road bumps. And traffic circles with road bumps. I think the Mexican Tire and Suspension Repair Consortium is behind it all, but you can't drive more than a few blocks without going around a circle, across a ditch or over a bump. And, to really make life fun, they put paving stones the pavement in spoke like patterns radiating out of the center of the traffic circles. This means if you go faster than seven miles an hour around one of these circles you better be really good at regaining control out of a skid. That doesn't stop the locals from driving like maniacs, but it does provide seconds of terror filled amusement as you navigate your way home.

Ann and I spent most of the day just hanging out on the boat. We tried to go to a fancy restaurant that evening but got lost trying to find it. The numerous police officers we stopped to ask seemed surprised that anyone would voluntarily talk to a person in uniform at night, but while being very polite and as helpful as possible, they didn't know where we wanted to go. Eventually we just gave up, pulled up in front of some roadside joint and had a mediocre meal.

She left the next morning, but not before making me take a picture with my favorite roadside attraction. I had the seal installed that afternoon, but we were missing the set screws that held it in place. They had fallen into the packing material, never to be see again. No big deal, Ann eventually found them when she got home, but it means that I won't be able to finish and test it all until the crew gets here with the new ones. Ugh. They are also bringing down another seal, which I'll probably install on the other shaft if there is time, or we stop somewhere. This boat is absolutely fantastic in that almost anything can be repaired on it without having to take it out of the water. I love how well thought out the design is.

I've also got to hang out a bit this week with a Dutch cruising couple, Marcel and Anok, and their one year old child Lev. We had bumped into them in La Paz, then in Los Frailes, then in Cabo, and now they are here in the marina as well. They've been cruising on a 27? foot trimaran called "Evasive", which was originally owned by Larry Flint, painted bright pink and called "She's Easy". When they bought it, it was tan, and had already had its name changed. Being less than perfectly fluent they didn't really grok the subtle meaning of the new name. They are thinking of changing the name back, because "Elusive" just doesn't capture the spirit of their adventure, and it sounds kind of shifty to them. I agree.

Unfortunately, they ran into some problems this week with the four stroke outboard that powers their boat. While motoring into harbor it broke free from its mooring plate and fell into the ocean, still running. Marcel was unsure what to do about it, and asked my advice. I suggested the standard things, like draining all the fluids, flushing the cylinders, changing the oil several times, etc., eventually we got it running again, and it sounded pretty smooth. "Okay", I said, "now change the oil again, run it an hour, then change it again after that." He did, and started it up. It seemed fine. "Wow, you got really lucky!" I said, "most motors that suck in water while running blow a seal, or crack the head, or worse." I left feeling pretty good about things.

A hour later Marcel came by and asked if I could look at the motor again. It seems there was water leaking out of the oil drain plug. Well, I checked it out, and sadly, there was water just pouring into the crank case when the engine was running. Very bad. Very, very bad. It seems he did blow a seal (or worse, maybe cracked the block somewhere), and would have to take the motor in to La Paz to get it fixed. Damn, just when I thought we'd cheated death. So, its off to the mechanics for them, and back to being a mechanic for me. The fun never stops.

In the meantime, work proceeds apace. I've got a bunch of wiring and plumbing done, have a bunch more to do, but should be ready to go by the time the crew arrives. We hope to leave here Friday night around 10pm, motor down to Cabo Falso and check the weather. If it is good we will run up the coast towards Mag Bay. If not, we'll wait another twenty four hours and try again.

So, if you are of a religious nature, please say a prayer to whatever God you worship, and ask him to put in a good word with Poseidon, tell him to spare Triton from his wrath, and grant us flat seas, calm winds and clear water. Getting round this point is considered one of the hardest bits of sailing there is to do, so we'll take all the help we can get. In the meantime, we watch the weather charts and listen to the HAM nets and hope for the best.

Cheers for now,

Robb


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