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Three Innovations That Have Transformed Cruisers's Lives Over The Past 15 Years


Cruising times have changed. When PassageMaker sold its first copy 16 years ago, our boats, and our lives it seems, were much simpler; the gear was uncomplicated and there was definitely less of it aboard any given vessel.

With a few exceptions, battery banks were smaller because they could be, many of the electrical parts we used were still automotive derivatives, and the first ABYC-certified electrician wouldn’t graduate until the following year. Using the Internet to access technical data on everything from the coefficient of expansion of Plexiglas to determining the preferred weight of motor oil for a particular engine was still something that was “coming soon.” And for those of us that did have Internet access, dial-up was the only option.

Boaters enjoyed cruising just as much then as they do now, they just did with less, although it didn’t seem like less because we had no idea what was coming. The Plexiglas query, by the way, represented one of my first truly useful and memorable Internet searches. I investigated this to determine why the Plexiglas windows of a particular boat kept leaking. It turned out they were too long, and when they were exposed to heating and cooling cycles, they expanded and contracted so much the sealant bond eventually failed, but frustratingly always a few weeks after the boat left the yard. Replacing them with conventional safety glass solved the problem. The information highway and, at the time, unimaginable gadgets galore were coming to a boatyard near you and it seemed to bode well for both the industry and the boat owner.


While there seems to be a “hue and cry” of late, calling for increased simplicity aboard, the fact is, humans don’t like to go backward. Once you’ve used a plotter, no matter how simple and reliable paper charts are, it’s tough to go back (you should still keep paper charts aboard).

There is a price to be paid for the conveniences we now enjoy and take for granted. Corrosion-resistant tinned wiring and connectors come to mind as an ideal example. The price is just right—a noticeable improvement in performance and reliability for a modest up-charge.

In some cases, the price is entirely too high. Overly or unnecessarily complicated, questionably designed, and often poorly supported gear isn’t worth the heartache it will cause down the road regardless of how new or innovative it may be or how lofty the claims of the manufacturers.

I recall salesmen routinely visiting the boatyard I used to manage, proffering wares that seemed to offer little improvement over what was currently available. Bottom barrier coats were one example, the existing product back then was tried and true, it had been around for many years, worked well, and the price was right. Yet, every year a few sales folks would stop by offering a new brand. Why, I would ask, should I switch when the product I am using works well and has a great track record? Is the new product significantly better, does it have a longer warranty, is it less expensive, or easier to apply? Maybe, no, no, and no was the typical response. I passed on these offers.

Many of my boatyard colleagues did try the new products, succumbing to the “it’s new and therefore must be better” syndrome. In nearly every case they lived to regret their decision as many of the products either failed to perform as advertised or the manufacturers were soon out of business or at least out of the marine industry. While today there are others, the tried-and-true product is still around. I still use it and it still works very well.

The lesson here is simple enough, scrutinize new products and concepts carefully, use critical, sound judgment processes, ask questions, ask for references, talk to others who have used it before parting with your cash, and just because it works successfully in other industries or applications doesn’t necessarily mean it’s well suited to this industry.

Finally, lest any reader believe I’m immune from falling prey to the “it’s new so I’ll try it” thought process, I once purchased several cases of “new-and-improved” corrosion inhibitor from a salesman who talked a good game. Indeed, the stuff worked really well, it was slimy and sticky, which was an attribute in that it clung tenaciously to anything unlucky enough to be bathed in its greasy sheen. I say unlucky because the odor it emitted was both repulsive and overpowering and if you managed to get any on your clothes or worse, your skin, you might be forced to discard the former and scrub the latter until raw in order to rid yourself of the stench. Live and learn.


Having made my case against new things, at least when it’s new for the sake of new, I’ll be the first to point out that the marine industry attracts creative genius and those that think out of the box. The boat business has seen its share of creative, economical, and worthwhile innovations that are well supported and offered by multiple manufacturers, which is ever important if you believe, as I do, that healthy competition serves the consumer well.

When I initially contemplated this article, one of the first thoughts that came to my mind involved a subject near to my heart, diesel fuel. Taking the thought one step further, and still nearer to my heart and the hearts of countless cruisers no doubt, is the subject of fuel filtration. Fuel filtration elicits no end of commentary from vessel owners and those in the marine industry, and I am routinely involved in both sides of this discussion. Constructive debate is desirable in that it tests the theories of those engaged in the discussion.

While there are many approaches and opinions when it comes to fuel filtration, professionals and cruisers often can agree that few things are more important than providing an engine with clean fuel. The goal of most cruisers is to ensure that their engines are both reliable and long lived, and feeding them ultra-clean fuel is one of the most important ingredients in achieving this end.

Since nearly the beginning of diesel time the method used to ensure that the fuel was clean involved filtration, often on multiple levels, giving birth to the now-ubiquitous primary and secondary filter approach. While this method works exceptionally well, it isn’t without its shortcomings. The main weakness of such filters is obvious to most vessel operators; they only work when the engine is running and because the volume of fuel pumped by the engine is comparatively low, the turnover rate is also low, limiting their effectiveness to deal with anything other than mild contamination. Even if they could capture contaminants more effectively, when they clog it compromises your number one onboard asset (after your first mate), the propulsion engine. What if you could utilize a filtration system at your discretion, even when the engine wasn’t running, without affecting the engine’s filters?


Enter the fuel polishing system. Today it seems like the obvious no-brainer: clean your fuel whenever you please while preventing your primary and secondary fuel filters from having to do the filtration heavy lifting.

When first introduced in the mid-1990s, the initial recreational marine fuel polishing system design offered users a host of valuable and hitherto unavailable features. While designs and manufacturers’ claims vary, generally, the traditional fuel polishing system was designed to maintain fuel cleanliness using a high-volume pump, often over 100 gallons per hour, along with dedicated large-diameter plumbing that would support such a rate of flow. Using this approach, the fuel could be cleaned at the user’s discretion, whenever he or she liked and for as long as was deemed necessary. Routinely “turning over” the fuel (the rule of thumb calls for pumping three times the tank’s capacity) mitigates a process known as agglomeration, where very small particles suspended in the fuel column come into contact with each other, forming larger, heavier masses that ultimately sink to the tank bottom. Even if new fuel isn’t brought aboard, the existing fuel is subject to the agglomeration process and air moving into the tank with daily temperature changes brings with it moisture, mold spores, and bacteria, all of which conspire to form a biocolony in the tank’s nether regions.

Depending upon the level of contamination, this process can eventually lead to the deposition of inches of contaminant. How long does it take? Again, depending upon the severity of fuel contamination, the amount of fuel that has been pumped through the tank, and the frequency of vessel use and climate, it could happen in a as little as a few months, however, it typically takes years. My recommendation for boat buyers is, if the vessel is used, you have no idea what’s there unless you open the tank or at least scrape the bottom. Remember, many used vessels have been sedentary for some time, either before they were placed on the market or while they were for sale. When a vessel is at rest, fuel isn’t being filtered by the engine and the agglomeration process continues.

In my work as a marine systems consultant I routinely communicate with clients who fill up, and in the process unwittingly get either severely contaminated fuel (in the most recent case the fuel within the filter sight bowls was so heavily fouled it was opaque), or fuel that is spiked with water (in another recent case tens of gallons worth). Dealing with contamination on this scale is both costly and time consuming. It nearly always involves opening the tanks for a thorough cleaning and if they don’t already include inspection ports, then the project includes adding them. If the contamination can’t be dealt with quickly, you run the risk of, at the very least, loss of propulsion or worse, loss of propulsion and inflicting damage on the engine. However, with a polishing system in place, the fear and anxiety that stem from taking on a load of contaminated or water-laden fuel is virtually eliminated.

Two of the key elements of the traditional polishing system bear reemphasis—a high-volume pump and dedicated plumbing whose diameter supports the related flow rate. With these elements in place, the polishing system is, in theory, capable of cleaning contaminated fuel in a relatively short period of time and, perhaps even more importantly, it’s also capable of maintaining the cleanliness of the tank provided that it’s properly plumbed. The latter is an extremely important tenet in the world of fuel polishing systems. In many cases, years worth of accumulated asphaltene, biomass “carpets,” rust, and water lie in wait, wreaking damage on metallic tanks until agitated. Once this material is stirred up, it is drawn into the fuel filter, nearly always causing it to quickly become overwhelmed.

Today, variety is the watchword where polishing systems are concerned and the choices you are afforded as a consumer are, for the most part, good ones. A wide array of polishing systems are available from a host of manufacturers, from the traditional dedicated plumbing, high-volume pump variety to micro-polishers that share existing fuel supply and return lines. If your goal is to keep the tank and the fuel clean, then you’ll be best served by one of the traditional high-volume systems, but be prepared for the cost of the installation. Aftermarket retrofits can cost $10,000 or more. If, on the other hand, you simply want extra, what I refer to as “supplemental filtration,” then one of the many smaller and much less expensive systems will likely fit the bill. Because the differences between these systems and their capabilities are significant, evaluate the specifications carefully before making a decision.


I clearly recall a boatyard customer whose vessel was in the midst of a refit. He agonized over the repower aspect of the job because “new” electronically controlled diesel engines were being phased in and he was deeply concerned that he’d have no choice but to use one for his boat. The word around town, he told me, was that electronically controlled marine engines were unreliable, what with all of those tenuous electrical connections and miles of wiring and multiple sensors, you’d only be able to work on them if you had a computer programming degree. And, I had to consider the source; he was a retired aerospace engineer.

At the time this customer wasn’t alone in this belief. Many folks looked askance at adding yet more wiring and, of all things, a computer, to what had represented one of the world’s most robust, simple, and reliable inventions—the diesel engine. I even quipped in an article or two that engine manufacturers, albeit as a result of impending stricter government-imposed emissions regulations, had succeeded in giving the diesel engine something it neither had nor needed, an ignition system that closely resembled that of a gasoline engine.

This wasn’t just dock talk, predictions from many industry experts were dire, indeed. What would happen to the sensitive electrical and electronic components in the warm, moist, salty confines of an engine compartment? What would all that vibration and heat do to a computer? What would happen if the vessel was struck by lightning (whether or not it affected the engine may be the least of the crew’s worries)? I shared some of these concerns; however, I didn’t believe the predictions were nearly as dire as they appeared for one simple reason. Thanks to my subscription to a diesel engine trade publication, I knew that electronically controlled diesel engines had been around for some time before they were thrust upon the marine industry. Over the road, long-haul trucks in North America, Europe, and elsewhere had been using these engines for several years; their emissions requirements typically predated off-road use. The folks who own and operate these vehicles and fleets are somewhat intolerant of unreliability; a broken-down truck makes no money and it loses money every minute it’s idled by a mechanical failure.

Long before anyone ever thought of installing an electronically controlled engine in a boat, trucks had racked up hundreds of thousands of over-the-road miles and while trucks and roads aren’t boats and seaways, roads that are dusty, bumpy, salty, and extremely hot and cold remain a harsh, demanding environment, particularly for all things electrical. Thanks to the crucible in which they were cast, electronically controlled marine diesel engines have, by and large, proven their detractors wrong.

That’s not the end of the story. Not only have electronically controlled diesel engines passed the acid test, operating successfully and reliably for tens of thousands of hours in the marine environment, they have excelled, offering their users more than their mechanical predecessors.

I love mechanical diesel engines. Who couldn’t love an engine that you can start with a hand crank (small one) and operate with no battery? Their simplicity and ingenious design is nothing short of sublime. Time marches on, however, and today’s lineup of electronically controlled diesel engines offer users a wide range of attributes, not the least of which is improved fuel efficiency. Mechanical diesel engines are saddled with an injection system that can only cope with one variable—load—and it can only achieve one injection per power stroke. Electronic diesels are capable of taking in a great deal of information about their environment and then tailoring the injection profile for maximum efficiency. Among their most remarkable feats is their ability to provide each piston’s power stroke with multiple injections of fuel, creating more torque and quieter idling. Electronic diesels still retain the diesel din, however, at idle and especially when cold, they are noticeably quieter and they produce virtually no smoke.

In addition to the efficiency factor, electronic diesel engines are capable of providing the user with a great deal of information, sometimes too much, including self-diagnostics. When I sea-trial an electronic diesel, I don’t need to bring my strobe tachometer, the engine display provides completely accurate and reliable rpm info, and I don’t have to make an educated guess regarding engine loading and how it relates to propeller selection. Among other things, the display will provide rpm, percent load, percent throttle position, fuel consumption (beware, fuel use is calculated rather than actual), and turbo boost, along with the usual voltage, oil pressure, and coolant temperature.

As a former mechanic, I’ll say that diagnosing and repairing diesel engines isn’t what it used to be, you need much more than a set of hand tools, a good ear, and experience, however, the electronic sword is double edged. When it comes time to diagnose a problem with a computer-controlled electronic engine, much like today’s automobiles, a technician with a laptop can extract fault codes that the engine has stored. This makes life considerably easier for mechanics, and likely less costly for owners.

My customer who dreaded the thought of buying the electronic diesel for his refit was able to get a legacy mechanical engine, which greatly relieved him. While I’m certain he’s happy with that engine and his decision, it’s very likely that the electronic engine would have not only served him well, it would have also saved fuel, been a little quieter, and less smoky in the process.


Known in the industry as SVRLA, or sealed valve regulated lead acid, AGM and gel batteries have been around for many years. While both were first offered to recreational marine users in the 1980s and ’90s, only in the last 15 years have they gained widespread acceptance.

I recall attending an educational seminar in 1994 touting, among other things, the virtues of SVRLA batteries. It seemed that everything they offered was far and away better than the legacy flooded battery. Since that time I’ve installed many SVRLAs in a variety of both power and sailing vessel applications and I believe it’s safe to say the jury is in; they do have much to offer.

Invented in the mid 19th century, in their present form conventional flooded batteries (they have sloshing, liquid sulfuric acid inside) have remained essentially unchanged for decades. While they’ve been tweaked and improved along the way, the technology is mature. High-quality flooded batteries are rugged, long lived, and generally perform well, some lasting for more than a decade, however, their shortcomings are well known to those who have used them. Their primary weakness is that they are slow to charge. Typically, their maximum charge rate is no more than 25 percent of their amp hour capacity. That means a flooded 400-amp hour battery bank could only accept, initially, 100 amps of charge. Because the resistance in a battery increases as it charges, that charge rate tapers off rather quickly, which means it could take three or four hours to replace 200 amps from this bank. Additionally, because the charge process creates heat and gassing, flooded batteries lose some of their water content with each charge. Eventually this water needs to be replaced. Forget to do this and you’ll quickly and prematurely kill an otherwise good battery. As flooded batteries charge they also emit acid vapor. You’ve probably seen this accumulate on battery tops, it doesn’t readily evaporate. I know I’ve encountered it many times because of the number of trousers and coveralls I’ve ruined as a result. Flooded batteries have one more trick up their sleeve, as they charge they produce explosive hydrogen gas, which has to be safely vented out of a battery box or compartment.

Nearly all flooded battery maladies are negated by switching to an SVRLA. The charge acceptance rate of SVRLA batteries is likely their greatest attribute. They are capable of accepting up to 50 percent of amp hour capacity for gels and 100 percent or more for AGMs, which significantly reduces the time it takes to recharge battery banks. SVRLA battery cases are sealed and slightly pressurized, which means that if properly charged, they won’t emit hydrogen gas or acid vapor and they never require the addition of water. If overcharged, however, they will produce hydrogen, so they still require ventilation. The electrolyte in gel batteries is immobilized as a gel, hence the name, by mixing it with very fine silica, while AGM electrolyte is immobilized in a glass fabric, making SVRLAs virtually leakproof.

So what’s the price to be paid for the convenience of using SVRLA batteries? As you might expect, they cost more, however, with competition amongst multiple suppliers and mass production, not significantly more than like-quality flooded batteries, and while there are exceptions, they tend not to last as long as similar quality flooded batteries. They require a specific charge protocol, which calls for something other than a stock alternator, however, if you are charging a large flooded battery bank, you’d benefit from the same approach.

In short, SVRLA batteries have made more energy-intensive vessels with larger battery banks and shorter charge times a reality and it’s likely they’ll be around for the foreseeable future.

Change, especially when it’s for the sake of change, can be problematic. Fuel polishing systems, electronically controlled diesel engines, and SVRLA batteries have, however, proven themselves as valuable, worthwhile, and not overly complex changes that have indeed changed the lives of many cruisers.

Steve owns and operates Steve D’Antonio Marine Consulting (, providing consulting services to boat buyers, owners, and the marine industry.