Once upon a time, we went whale watching in Bahia Magdalena.
Here is somebody else’s video of what happens when it happens, in an adjacent bay, on a different boat:
When Bright Water was anchored in the Pacific Mexico open-ocean bays of Puerto Vallarta and Tenacatita, there were several days where the wind died and we wallowed in the swell, rolling from side to side, sometimes violently.
So we bought a set of four Davis Rocker-Stoppers at a marine garage sale in Seattle. We didn’t pay much and we didn’t really think we’d need them.
But when the seasonally extraordinary winds caused the swell to wrap around into the anchorage at Isla Coronados, we got the plastic cones out of the lazerette.
Davis wants you to rig them off the rail, and many people rig them off the end of the boom, but we used the whiskerpole and rigged them as far from Bright Water’s centerline as possible. It’s all about leverage. Also, the topping lift pulley wouldn’t have been fair if we used the boom and I was worried the line would chafe through. Using the spinnaker halyard to lift the end of the whiskerpole was better, I think. We rigged fore and aft guys to keep everything quiet.
We used a 10# weight belt on the bottom end of the rope, which was more than enough weight. The effect was instant and awesome. Even though Davis recommends 8 cones per side = 16 cones for a boat our size, we think four rigged this way is adequate. Bigger ocean swells may eventually prove us wrong.
You can see the sardine school in the lower right corner.
Edit: A little math. The drag force caused by pulling the cones through the water is proportional to the square of the speed, and the speed of the cones (for a given amount of rocking) is proportional to the length of the whiskerpole. In addition, the damping effect of the force caused by dragging the cones through the water is proportional to the length of the whiskerpole. So, making the whiskerpole twice as long makes the cones 2x2x2=8 times more effective. It’s Science!
All boats are electrochemical batteries. The different metal parts sticking into the seawater interact with each other, pick out a loser, and pull atoms off that part into the ocean. Eventually, the losing part disappears altogether.
Engineers, techs, and wandering drunks have some fairly serious disagreements about the details of how to address this metallic warmongering, but generally we connect all the metal parts together inside the boat, where conditions are more favorable for metal parts, and we put a piece of zinc or magnesium on the wet side of the boat that takes one for the team. The sacrificial anode purposefully becomes the weak link, protecting the other metal parts by giving itself to the sea. We replace the sacrificial anode periodically to make sure the important parts are protected.
The only sacrificial anode on Bright Water is a zinc collar mounted on the shaft just forward of the prop. It lasts about six months between replacement, which is fine. However, the electrical path between the anode and the sea and the rest of the boat runs through the bearings of the transmission. Typically you don’t want to run current, even tiny current, through moving parts. The current can cause micro-pits which become macro-pits which become major pits. Then the money flows like water.
We installed a shaft brush on Bright Water. A conductive graphite pad is pushed against the stainless steel shaft, and a wire connected to the pad carries current around the transmission bearings directly to the engine block ground post. This is pretty normal stuff, but an amazing number of boats don’t bother with it.
(Edit) Here’s a pretty good summation about the bigger picture, although the ground plates that he talks about have been discredited because the additional surface area of the sintered plate contacts exactly the same amount of seawater as a solid plate of the same size: http://www.westmarine.com/WestAdvisor/Marine-Grounding-Systems
We avoid this added complexity by never, ever, ever plugging Bright Water into shore power, especially in Mexico. I don’t think we even have a power cord on board. Never swim in a Mexican marina. If the docks aren’t screwed up, some of the boats in the marina will be. Based on what I’ve learned, I wouldn’t swim in any other marina, either.
If we get a SSB or HAM radio, we’ll have to do something about RF grounding, but I’m leaning towards a counterpoise instead. Lots to learn.
Bright Water has terrific Bomar Ocean Hatches, but the gaskets were over-due for replacement. Bomar sells the correct tubular gasket with a double-sided tape mounting system. Easy. Except for the removing-the-old-gasket-from-the-round-groove part.
Nancy’s side came out clean with just a little gentle and careful persuasion.
Shockingly, my side quickly turned into a complete disaster. Glue and torn gasket everywhere. It was hopeless.
I got out the power tools and sharpened the barrel of a 7in1 screwdriver using a countersink bit.
I then chucked the whole thing in the drill and used it to clear the groove. It made a mess of the mess, but worked well.
Installing the gasket was easy. Good as new.
Like many boats her age, Bright Water has simple friction latches on the cabinet doors. If you mistakenly take her out in the ocean or a particularly rough lake, the contents of the cabinets tend to fly across the saloon, harshing your mellow and perhaps even triggering profane thoughts.
Many people do many things to contain their cabinet contents. We went to Walmart.
The “Yacht Fittings” section was not helpful, but the same doo-dads that keep babies out of your sink chemicals can keep cabinet chemicals out of your yacht.
They don’t do anything once mounted until enabled with a small button on the device. Once enabled they keep the cabinet shut until you hold a strong magnet directly over the device on the outside of the cabinet.
Diesel engines use a signal from the alternator to synthesize a tachometer signal. When you change your tachometer or your tachometer pulley, you need to re-calibrate your tachometer.
Here is the Perkins-Sabre document on how to set the electronic tachometer on your brand-new engine. Read it if you want. It may be the worst tech writing to ever be thrust upon unsuspecting customers: PerkinsSabre Tach Programming.
It took me several years, but I finally figured out what they’re saying. Here’s the process.
Figure our your drive ratio. With an 8″ OD crankshaft drive pulley and a 2.625 OD alternator driven pulley, my ratio is 8/2.625=3. Multiply that times the number of poles on the alternator (usually 6). 3 x 6 = 18 alternator pulses per engine revolution.
This is a picture of the back of the control panel. There is a greenish/blue wire hanging out of the back of the tach. That is the programming wire (called pin 11 in the documentation). Right next to it, there are a bunch of black wires connected to the circuit board. These are all ground wires. Clip a test lead to the programming wire and a different test lead to the ground pins.
Get where you can see the front of the panel and hold both test leads at the same time. This would be a good time to find your reading glasses, too. There is a decimal point on the display that is approximately the same size as no decimal point.
Ground the programming wire (PW).
Turn the panel ON (do not start the motor). The beeper will beep. Ignore it.
Unground PW. The display will change. Pulse-ground PW to change the digit, hold-ground PW to move to the next digit. Beware of the tiny decimal point. Once you’ve got the ratio set correctly (18.0, in my case), ground PW and turn the switch off. This will save the setting. If you screw up or get confused, turning the switch OFF with PW un-grounded will not save your changes.
Clearly you can screw things up if you do this wrong. Also, you’re on your own. If you do something because somebody on the internet said to and it doesn’t work, it’s your fault. Feel free to contact Perkins/Sabre and tell them to fix their documentation. Tell them you know about this guy that can rite gud and is remarkably affordable.
We have a great big alternator. 210 amps at 12 volts – over 2500 W. Huge.
It’s driven by two large V-Belts off the main crankshaft. In the olden days, you would buy a matched set of V-Belts to use in a dual application because it’s important that they are the same size. Exactly.
Modern manufacturing methods mean that the premium belts are uniform enough that you don’t need to buy them in pairs.
We’ve had a problem where the tach would jump around when the alternator was producing maximum power. I always figured it was electrical noise and would go wiggle the connectors. Eventually the tach would settle down.
I never suspected belt tension, since I regularly check and re-tighten the belts. However, the belts aged differently. The inner belt stretched slightly, and under heavy load would slip slightly, heat up, and transfer all the horsepower into the outer belt. Eventually that belt would also heat up and slip – just enough to show up in the tach needle (diesel engines get their tach signal from the alternator, since there is no distributor producing an electrical pulse). You can see the belts are now differently-colored from the aging.
So, two new belts from spares and everything was right in the world.
We’re back in the Pacific Northwest. The wood stove is lit and unpacking is underway.
In Mexico, we used about 70 gallons of fuel to cover approximately 500 miles for an average speed of six or seven knots. We sometimes had wind to assist our progress. Of course, sometimes we had wind in opposition. We ended the trip with approximately 1070 hours on the motor.
On the drive to and from Mexico, we used somewhere around 180 gallons of fuel to travel about 4000 miles. We ended the trip with just over 250,000 miles on our Mercury Sable Wagon.
If you figure 50 mph average lifetime speed, that’s about 5000 hours on the motor. Well past it’s “Best Used By” date, but we’re happy with the car. The Perkins-Sabre in Bright Water should last more than twice as long.
In Mexico, we spent significant time and resources tracking the weather, and were never surprised. Despite spending hours on the internet, 0n the trip home we were surprised several times by small snowstorms and freezing fog. Dropping into Idaho was particularly…special.
The sign says “Less Than 500 Feet Visibility.” The small sign just past it says “80 MPH.”
That’s what flashers are for. Oddly enough, the other drivers were as terrified…um, cautious, as we were. Nobody passed us in the fog. Everyone stayed way away from everyone else.