Off To Tahiti

After about a week of waiting in Tahanea, OMNI Bob forecast a short window for Duet to reach Tahiti. Since our plane home was leaving in less than two weeks and we needed to get the boat ready to be left alone for three months, we tore ourselves away from Tahanea and our cruising friends, with promises to return on our next visit. We exited the atoll just before low slack at around 11AM local time, with a 40 hour journey putting us into Papeete Harbor around dawn. The weather was relatively settled, with the occasional squalls, none of which approached the ferocity of the first one on our departure from Nuku Hiva.

Our course from Tahanea to Tahiti is shown below on the backup computer in night mode. The chart is north up and Tahanea is in the upper right corner, while Tahiti is at the end of the course line in the lower left.

Duet, naturally, went faster than we figured, and our Papeete arrival time moved up from dawn to 2AM. We wrote Tehani, to see if we could enter the harbor in the dark. The charts are accurate and everyone we talked to said it would be no problem. Harbor Control, however, was having none of it. We could enter, they said, but we must tie up at the municipal marina downtown, as we couldn’t start for our marina until 6AM, when it was safe to cross the airport runway in daylight.

Tahiti, like most Society Islands, is surrounded by a reef, through which there are passes. Once you get through the pass, you navigate between the reef and the land to get to your harbor. For those readers who have not navigated the Papeete area, the main harbor is on one side of the entrance through the reef. The airport is on the other. The pass is straight and well marked, with a lighted range. It is 40-50 feet deep and about 360 feet wide. It faces northwest, and is therefore dangerous in northerly swell and wind, which we didn’t have. Actually, we had remarkably calm weather for our entrance to Papeete.

Marina Taini, where Duet was to stay, is about 5 miles SE of Papeete via water. It is reached through a narrow, well marked channel running between the reef and the land. The channel’s main feature is it crosses both ends of the airport runways. So, when a plane takes off or lands, it goes right over the channel at a relatively low altitude. For sailboats, with a 65 foot mast, this is a considerable issue. For Duet, with an air clearance of about 27 feet, it’s not such a big deal, but there are strict procedures for how all boats cross the runways, which we had to follow.

The map below shows the entrance to the harbor, the runways and the channel we were to traverse to the marina, which is in the lower left corner. Duet wants to stay in the dark blue water. 

Since we didn’t want to try to moor at the municipal marina in the dark, we slowed down. As usual, Duet didn’t slow down enough, even at 1000RPM, so we ended up chugging up and down off the NE coast of Tahiti between around 1AM and 4:30AM, to ensure a daylight arrival at the harbor. We stayed on the NE side, rather than move around nearer the harbor entrance, because the harbor is on the narrow channel between Tahiti and Moorea, which often has considerable wind funneling through it. Since the weather was from the prevailing direction, namely SE, we were able to wait in the lee of Tahiti, where it was quite calm.

Coming into the harbor was pretty interesting. First, we had a freighter overtaking us several hundred yards off our stern while we were lining up for the entrance, which is always a little stressful. Adding to that was the fact that neither of us have gotten more than 3-4 hours of sleep that night, as we had first planned to continue and arrive in the dark, so we had changed the watch schedule to let Ron sleep earlier to be ready for a 2AM arrival.

Then we had to rethink to arrive in the light, which really messed up our sleeping plan, as now Ron was rested at 12:30AM and Nancy was tired. But we didn’t want Ron getting tired doing station keeping, as we’d rather he was rested to enter the harbor. So Nancy took over again around 2AM, so Ron could sleep again until 4:30 or 5. Nancy then slept until about 15 minutes before we entered the pass at just after 6AM. The other problem was this trip was so short (40 hours) that we hadn’t gotten any rhythm going on the sleep front, so we hadn’t gotten much sleep the day before either. Suffice it to say, we were tired.

Anyway, the pilot boat called us as it passed us on the way to the freighter and said go ahead, the freighter doesn’t have clearance yet, but call Harbor Control before you enter. So we called Harbor Control, who said come on in. Fortunately everyone spoke English, or at least some variant of it. We started in, but just then out came a massive high speed ferry. The ferry decided to cut across our nose, rather than wait for us to pass down their port side, as is the convention when two boats meet. This is the equivalent, on land, of cutting someone off at a light. We didn’t realize what the ferry captain had in mind, as sometimes it’s hard to figure out who is doing what in a narrow channel, so Ron continued on his course for a standard port to port pass. It is important to follow convention when meeting other boats, otherwise no one can figure out what you are going to do next.

Ron’s move wasn’t popular with the ferry, as it meant she had to change course to get around us. She did, but she also stepped on the hammers, came up on plane in the channel and blew down our port side. This maneuver left a 3-4 foot choppy wake, which Duet plowed straight through. For us the wake wasn’t a big deal, Duet’s 42 tons going 8 knots, guided by her bulbous bow, deep keel and big rudder, coupled with active stabilization, can flatten out some pretty big bumps. The ferry captain, however, couldn’t have known this, and he had to know he was going to leave a big wake. That said, we understood the move, the ferry has a schedule to keep and we were in the way.

This is a picture of a ferry like the one we saw, courtesy of Google images.

Then the tug for the freighter decided to come out. We passed him easily enough, port to port. The second high speed ferry kindly waited for us to clear the pass before he started his exit. At this point, we figured out that the buoys were different than at home, so the green is on our right when we return to harbor, instead of our left. This is new for us, since Papeete is the first place we have seen buoys since we got here. Fortunately, this was pretty obvious on our electronic charts, and the pattern continued down the channel, although there are a lot of other yellow and white buoys as well, which delineate the inside of the reef where it meets the channel. It is also easy to see the shallows, as a lot of debris and trash is stuck there.

Having sorted all that out, we call Harbor Control again to ask permission to transit the airport runway. While we were doing that a jumbo jet took off about 100 feet above our heads, just in front of us. Harbor Control asked for our “address” which turns out to mean “air draft” in a heavy French accent, namely they want to know how much we stick up above the water. Once we calculated that in meters and reported back, we got the OK to pass. Then things calmed down a bit, until we got to the marina.

The marina said they’d send a boat out to lead us in, which sounded pretty good. They also said a starboard tie would work. So Nancy rigged up lines and fenders to tie up on our starboard side, out comes a dink and off we go. The dink barrels into the marina and we immediately lose sight of him in the warren of docks, fairways and med moored boats. Various people on the dock t-heads are yelling and pointing in all directions. They are yelling in French, which isn’t very helpful as we don’t speak French. They, of course, have no way of knowing this, so they wonder why we aren’t doing as they ask.

Lacking any substantive information, other than the dinghy might have disappeared behind the last dock, as we don’t see it anywhere else, Ron continues straight on until the last fairway, where we run out of road. Fortunately that turned out to be it, but it’s a port side tie. So Nancy runs around in circles and gets all the fenders and lines on the port side, and the dock guys help us tie up port side on. The dock guys leave. We can’t get off, because they tied the bow in too tight and the stern won’t come in far enough for us to reach the dock. Ron extends the bow line and we manage to get off. We’ve arrived!

Marina Taini shown on the north up map below. The main entrance is in the center left, you can just see a dinghy speeding in. Duet is moored on the upper innermost north south facing dock.

We share a hug, calculate that we have traveled just about 3,900 nautical miles in the 9 weeks since we left Mexico, and sit down for our standard arrival breakfast of eggs, toast, fruit and coffee, rather than beer, as we have things to do. We then head off to the local restaurant, where we finally meet Tehani and her team face to face. We fill out some paperwork, give her a list of what we need and generally get organized.

The next day Heirani, one of Tehani’s folks, plus a nice young lady who is interning with Tahiti Crew, drove us downtown to get our spare starter tested. As regular readers may recall, the main engine starter acted up the day we were to leave Mexico. While Ron and Sean could find nothing wrong with it, and it has behaved perfectly since, it will be replaced with the spare and rebuilt, just in case. The spare came with the boat and, as far as we can tell, is the same age as Duet, namely 17. So Ron felt it made sense to make sure it worked, before going through all the effort to install it.

Dieseltec, a local shop, put it on a test bench and carefully secured it, as starters can go walkabout when they are activated, wired it up, and bingo, it started. So that was a major blow for freedom. Ron also figured out, he hopes, how to get the old one off without having to remove much of the equipment on the port side of the main engine, so that was good. He does, naturally, need one new tool, but it should be easy to get. He will replace the suspect starter with the spare when we return in late August.

The spare starter, resting after it’s journey downtown.

We also purchased an adapter for the local electric. Marina Taini is wired for single phase 220V, which Duet cannot accept, as we are a two phase 120V boat. We do not have an isolation transformer, which would create two legs of 120 from the incoming 220. Tahiti is, however, 60hz, so that’s good. This was the first test of Ron’s new foreign power electrical installation, which is actually only half done. The half that is finished, namely the special plug on the transom and the wiring from that to one of our 100 amp chargers, which in turn powers one 3KW inverter/charger, worked just fine.

Ron wired a local plug into one of our cord adapters to connect us to local power. It is 16 amp at 220V.

Below the other end of our power cord is plugged into Duet’s new “foreign power” plug. We have a right angle adapter so the plug is not sticking out where it can be inadvertently bumped by someone on the swim platform.

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Since the second charger, the second inverter/charger and the switching to manage larger loads aren’t installed yet, Duet is running on a combination of dock power and the generator if we need air conditioning, the dishwasher (which doesn’t like inverter power) or the washer and dryer. Ron will finish the system when we return. That will allow us to run one or two air conditioners on dock power. The washer, dryer and dishwasher will always need the generator.

Ron then started on his long list of oil changes, fresh water flushes, etc., that are standard when we leave Duet. Nancy found the supermarket, so we could have some fresh fruit and vegetables, and then started on her list, which includes arranging for interior and exterior cleaning, making sure our paperwork is in order, inventorying what’s on board, figuring out if we can replace what we need locally or need to bring it from home, etc.

Changing the impeller on the generator’s raw water pump.

In addition to his usual boat storage tasks, Ron also focused on the continuing issue with the Naiad stabilizers. As regular readers know, our stabilizers gave up the ghost halfway through our 2,700 mile journey from Mexico to the Marquesas. This was a character building exercise, but one we’d rather not repeat, so repairing the problem was high on Ron’s list. The initial issue, namely the disintegration of the belt that drives the stabilizer’s hydraulic pump, was easy to fix, just install a tougher belt. Diagnosing why it self destructed however, requires figuring out the cause of the hydraulic pressure drop, which occurs when the fins are working hard and rapidly calling for high pressure.

In addition to the problems with the fluctuating pressure, we also had issues with the fins “chattering” while we were underway across the Pacific. This means the fin can’t find it’s center, so when it moves across it’s arc it just keeps moving back and forth very rapidly, creating a “chattering” noise. The fin finds center using a potentiometer, which is a wire coil that the fin sensor moves back and forth across. The sensor knows where the center is on the coil. Since the fins spend a lot of time at center, when the boat isn’t moving, the center of the coil becomes worn and the sensor can’t find it. This is a common problem and replacing the potentiometer is usually the simple fix.

Below is a standard potentiometer technical diagram.

A potentiometer like the one Ron and Sean installed.

Unfortunately, it wasn’t so simple in Duet’s case. As readers may recall, Ron, with a lot of help from Sean, replaced the potentiometer while we were running from Mexico to French Polynesia. Since it didn’t fix the problem, we then started trying to figure out what else might be wrong. It turned out that the problem was electrical, and Nancy diagnosed it, which, with an electrical problem, is unheard of. When the dishwasher ran, the fins chattered. When it stopped, the chattering stopped. When the microwave ran, the fins chattered. When it stopped, they stopped.

Chris Fontaneau figured this one out, once we were able to give him clear symptoms and correlation. Our Naiad system had an older DC to DC converter for the Datum electronic head. The Datum needs clean 24V power, which the converter makes from Duet’s 12V power. The older converters, however, are notorious for providing less than clean solid 24V power. When Ron tested ours, it wasn’t delivering anything near what the Datum needed when there were large inverter loads, like the dishwasher and the microwave, drawing on Duet’s electrical system. Karen, from Daybreak, hand carried in a new converter, which Ron installed. Presto, problem solved, dishwashers and microwaves now run with impunity on Duet.

The new DC to DC converter, you can see the checked box indicating it’s specs.

Ron has spent a lot of time with Christ Fonteneau of Fonteneau Yacht Services in San Diego on our stabilizer issues. Chris has gone way beyond the call of duty, even sending Ron detailed technical schematics, plus annotated pictures, on how to service and/or diagnose several potential problems. As part of this ongoing conversation, Ron recalculated the loads on the hydraulic pump and the belt, using Naiad’s standards for Duet’s installation. This engineering exercise made it clear that our original belt wasn’t man enough for the task it had been set. It was replaced with a heavy duty Gates Kevlar B52 belt called a Predator, which is capable of delivering twice the horsepower we need to the pump without breaking. Karen, from Daybreak, hand carried two of these belts to us in Nuku Hiva and Ron and Sean immediately installed one to see how it managed.

While the new belt has run well and shown no signs of strain, the hydraulic pressure still fluctuates. These fluctuations vary with the main engine RPM, namely low RPM equals more frequent pressure drops, in an equivalent sea state. The fins run without alarming, and, in relatively calm seas states there are very few variations at cruising RPM, but in the long run this needs to be fixed.

So Ron and Chris went back to the drawing board. The next question was do we have a large enough hydraulic pump? Some more math from Ron, using tables provided by Chris, and the answer was yes. The pump is relatively new, having been replaced in early 2015. It is not leaking and appears to be performing as specified. It is also has the correct part number, which, while it sounds a bit farfetched, wouldn’t be the first time an incorrect part has been installed.

In the meantime, Ron has spent quite a bit of time with the Naiads while we are underway. Part of that time he has spent listening to various components with a stethoscope, and he has noticed that the pressure relief valve is clicking when the fins demand high pressure. This may mean that the valve is clogged, or it’s spring is no longer effective. So Chris sent another set of documents on how to service the pressure relief valve.

Once Ron disassembled the valve, it became apparent that the popit, which closes the valve, was damaged. One side of it is fine, but the other is scored by wear. This suggests it might not be closing properly. Replacing the popit might solve our pressure fluctuation problem, but, until we get a new one, replace it and do some sea trialing of it, we won’t know for sure. We will take the damaged valve to Chris when we visit San Diego in June to get his opinion and to get a new one. Until then, the Naiads are on hold.

You can see the scoring on the nose of the popit in the photo below.

If it’s not the pressure relief valve popit, then Ron plans to work his way through the other valves, solenoids and gaskets in the system, as any one of them could be malfunctioning, either all the time or intermittently. Since we aren’t leaving French Polynesia for a year, he’s got some time to figure this one out. Also, we won’t be making a long low RPM journey in the foreseeable future, as the legs to Australia are much shorter than the big jump to the Marquesas. Ron will eventually fix this, it just may take some time.

Ron also took apart the fuel supply manifold, as we have had several small leaks at the valves. He believes this is the source of the very small bubbles that have been appearing in the Racor fuel filters. Over time, the valves wear out, so he is replacing all of them. We are hoping that will solve the problem. If not, the manifold itself will need to be replaced, as the fittings where the valves screw on may have worn beyond recovery. Ron already replaced two valves before we left Mexico and those have not leaked since, so we are hoping that the rest will also make a complete recovery, without having to replace the entire manifold.

One of the fuel manifolds, sans valves

New valves being installed. 

We have been having some weird smells and intermittent damp in our dryer. It had finally reached the point where things weren’t drying properly, so it moved up the list. Ron spent most of a day taking apart and cleaning the dryer’s vent, and some of it’s internal bits. All were heavily covered in mold, which we figure has been slowly growing in there for years. During this exercise, Ron noted that the belt that turns the drum is badly worn, so it is on the list to be replaced when we return in the fall.

Some of the considerable mold in the dryer.

Duet has worked hard over the last three months, she has covered nearly 4,000 miles, much of it in the open ocean, and we have lived entirely on the anchor, which works the systems harder. She was due for some TLC. We have been very pleased with the way she has performed as we have stretched her legs and can’t say enough about how much we like the Nordhavn 50. The hull is sea kindly, as we proved by testing it without stabilizers, the boat is comfortable to live aboard, with enough creature comforts to keep almost anyone happy, and she wears well. We do wish she carried a bit more fuel, but we’d guess that is true of almost any boat we would use for this kind of long distance work.

We will be spending the summer at home, while Duet takes a well earned rest. We will return to cruising at the end of August. We wish our readers a pleasant Northern Hemisphere summer or a mild Southern Hemisphere winter.