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The engine is the heart of a vessel. The boat performance depends on it. With the right motor, you can breathe a new life in your old boat. It will also lower maintenance costs, increase uptime and improves fuel efficiency. At Alberni Power & Marine, our experts help you extend the life of your beloved vessel and repower boat engines with ease.

Total Cost of Ownership (TCO) Focused Re-Powering

We plan the repowering a boat depending on its specifications and how its system is running currently.
It covers selecting the perfect engine, the supporting technology or accessories the vessel may need, estimating the delivery time & budget, and determining if any other additional work is required. The selection also depends on your engine room space, the current boat motor's footprint and what you want to achieve in the future.

The result would be a smooth, proper and affordable repowering process that ensures the best technical solution while matching your boating style.

Why We Are the Right Partner?

We know what it takes to repowering a boat. That's why our team carefully attends to all your needs and keeps the engine configuration sustainable to gain the right outcome.

Our trained professionals help boost your boat performance by optimizing the motor horsepower, propeller and other parts' configurations. They not only give you suggestions but ask questions to you for a better understanding of your preferences and future needs. It allows us to make a complete breakdown of technical requirements and provide you with a detailed quotation. The outcome is a 100% benefit and excitement on for our customers.

If you still have any questions about repowering the boat outboard, feel free to get in touch with us anytime.

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Repower Your Boat with Alberni Power & Marine

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The engine is the heart of a vessel. The boat performance depends on it. With the right motor, you can breathe a new life in your old boat. It will also lower maintenance costs, increase uptime and improves fuel efficiency.

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Have you ever wanted to repower an old boat that is collecting dust in your garage? Below are a few tips you can use to make your outdated boat one of the best in the water! At TNT Custo m Marine we care about your boat and w ant to help in any way possible. If you are planning on repowering your boat, our rebuild and repower experts are the best in the industry and willing to help. To schedule an appointment to repower your boat contact us at 305-944-2118 or tntrace1@aol.com.
Today's four-stroke outboards are more reliable than ever before with fly-by-wire controls and onboard sensors that maximize performance and efficiency. But, as my Roman forebears used to say, caveat emptor: The four-stroke solution is not the singular magical fix ideal for repowering all boats. What boats are we talking about? What are the challenges? What should you do before repowering? Here's the scoop.
Tips for Repowering Older Boats
The first generation of four-strokes all had one thing in common: They were heavy. When you added all of those extra four-stroke parts, like an oil sump, valve train, etc., the engines definitely increased both their mass and weight. For example, the Yamaha F200 and F225 four-strokes weighed more than 600 pounds. A 200 horsepower two-stroke engine of that era might have weighed 425 pounds. Expect today's best 200-hp outboard motors to have some weight, especially 4-stroke models.

After 2014, just about any maker's 200-hp outboard V6 engine costs upward of $20,000 installed, depending on your gauge package, controls, installation, etc. Although it doesn't burn pricey two-stroke outboard oil, it does require additional maintenance, like oil changes every 100 hours of use and valve adjustments at every 300 to 400 hours, expenses that don't impact two-stroke owners. Plus, four-strokes that deadhead half of their cylinders with every turn of the crankshaft need more cylinder mass to compete with the prop-shaft sea horses generated by two-stroke power plants that are firing all of their cylinders with every rotation of the crank.

If you are repowering a newer boat, going with a four-stroke repower is probably nothing to worry about. But when considering a new outboard for a pre-2002 vessel, there is a concern regarding which solution will work best, since these boats likely weren't designed with the requisite buoyancy aft that is needed to keep cockpit scuppers above the waterline with added weight on the transom.

1. Loss of ability to self-bail

2. Possible swamping with open transoms

3. Porpoising

4. Slow planing

5. Poor visibility forward

If you have to stick with a two-stroke due to either weight or mass, Evinrude E-TEC and Mercury OptiMax two-stroke direct-injection V-6s should do the job. Sure, you'll have to buy some two-stroke oil in bulk, which adds to the cost-per-mile of boat operation, but you'll never have to do an oil change, swap an oil filter or adjust valves, all of which add to annual operating costs.

Also, four-strokes are losing weight, which should help when repowering an older legacy boat. Yamaha has an in-line 2.8-liter F200 that tips the scales at a svelte 487 pounds, which is actually lighter than a two-stroke 3.0-liter V-6 OptiMax. Not to be outdone by the competition, Merc has its own four-stroke 150 hp - an in-line-4 with a 3.0-liter block that has room to grow. It tips the scale at 465 pounds. The valves on this Merc 150 never need adjustment, which will lower operating costs. An outboard motor weight comparison is a must-do when considering engines to repower your boat.

If you need to focus on outboards in the 225 hp to 300 hp range, there are plenty of outboard motor repower options. Yamaha's Offshore series (225, 250, 300 hp) provides the power and torque of a 4.2-liter V-6 block but lowers the overall weight of these triplets to an incredible 562 pounds. This mechanical miracle was accomplished by taking out the six-pack of steel-cylinder liners, which opened up the bore volume, which was then plasma-infused to provide a super slick surface to reduce piston-ring friction.

Hopefully, some of the lessons I've shared about repowering older boats will help you when it's time to repower yours. To see a chart of horsepower and transom weights of outboard repowering options, visit boatingmag.com/repower-options.

Should You Repower with a Single Outboard Engine Instead of Two Smaller Outboards?
Have big, super-powerful new outboards changed the repower game by allowing multiengine boats to be propelled by just one engine? It's a theory that's thrown around here, our Editor-in-Chief opines on the viability of that theory.

Outboards like the 557 hp Seven Marine 557 and the 350 hp Mercury Verado and Yamaha F350 can provide another repowering option for older boats, those designed and built before about 2002. This is particularly true if the boat in question was originally powered by multiple outboard engines.

For example, if your boat is rated for two outboards and 400 hp, you might consider installing a single 350 hp outboard. Doing so would net you somewhat less horsepower than the original twin installation. But with only one gear case creating drag in the water, compared to two gear cases creating drag, comparable speed and performance would likely be attained. Additionally, the price and complexity of the installation for one big single engine can cost less than those for multiple engines, since fewer gauges, wiring harnesses, and propellers are required, and controls and steering equipment are simpler. Consider the cost to install one outboard motor or two engines.

So why doesn't everyone do this? There are several reasons, and the first is that these monstrously powered outboards deliver enormous amounts of torque, possibly more than your older boat's transom can handle. Furthermore, unlike with multiple engine installations, all the power and torque transmitted to the boat are concentrated at one spot on the transom instead of spread across multiple locations on the transom.

Also, consider the cost Safety concerns are another reason why swapping out two or more lower-powered outboards for a big single engine isn't common. As trustworthy as outboard motors have become - they may now rank as the most reliable propulsion type in the history of marine transport - boaters who cruise far from shore still rely on the redundant safety of multiple engines: Should one breakdown, the other(s) can get you home.

Then there is dockside maneuverability. While outboards do not respond like inboards - due in part to torque, propeller size and a pivot point farther aft - a multi-engine boat handles close quarters better than a single-engine boat. Multiple engines also allow boaters to avail themselves of the convenience of the joystick control systems now available for outboards. Swapping multiple engines for one big engine is a great idea. But not every boat is up to the task.

Complete and original article published on boatingmag.com

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Tips for Repowering a Boat - tntcustommarine.com

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Have you ever wanted to repower an old boat that is collecting dust in your garage? Below are a few tips you can use to make your outdated boat one of the best in the water! At TNT Custom Marine we care about your boat and want to help in any way possible.

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You love your boat. It has taken years to get it outfitted and made as fishing efficient as possible, but your outboards are getting long on hours and you need to know those engines will get you home from the blue water trouble free.

Repowering provides the comfort that having new engines on the transom provides, but it is also an opportunity to take advantage of the latest technology and the benefits provided by that technology. I have repowered over a dozen boats throughout the years, so I speak from firsthand experience regarding the real world challenges and costs. There were both painful and pleasurable lessons that I learned and I share them with you in this month's Boat Sense feature.

FOUR-STROKE VS TWO
The latest boating industry stats that I reviewed at last year's Ft. Lauderdale Boat show indicated that for new boat sales, four-stroke outboards continue to dominate the scene, with over 90 percent of new boats sold having four-strokes hitched to their transom. This trend started gaining momentum back in 2002 with the introduction of Yamaha's first big-block V6 F225 four-stroke and was accelerated by the 2004 introduction of E-10 gasoline and has been continuing its forward march ever since.

As next-gen four-strokes have become lighter, less complex and more reliable, more coastal, river and lake boaters are becoming increasingly at ease with 100-hour oil changes (equivalent to changing their car's oil every 3,000 to 5,000 miles) replacing the requirement to add two-stroke engine oil to their fuel or oil injection tank. But two-strokes have advantages as well, the biggest being their power to weight ratio. BRP's Evinrude is all in with this bet, with 100 percent of its outboard manufacturing efforts dedicated to E-TEC and E-TEC G2 production. Mercury Marine continues to offer its OptiMax two-strokes and Tohatsu/Nissan still produces a number of small and midrange two-strokes that employ a similar direct injection operating system to Merc's Orbital technology.

I ran Merc OptiMax 200 V6s for five seasons (repowering each year) on my old Phoenix 27 charter boat, and they actually achieved better range and fuel economy than the three sets of Suzuki DF225 four-strokes that followed the Mercs. They were faster overall, faster at slower RPMs and the direct injection outboards popped that boat up on plane with a full load faster than any four-stroke. Plus they were 100 pounds lighter each and kept my aft scuppers out of the water, a critical safety requirement. Looking forward, there are a lot of next-gen four-strokes that I would like to own and run, but I'm not shunning two-strokes either. I am keeping my mind and options open. When comparing one operating system to the other, you need to look at all of the facts and then make the right decision that is best for your situation.

The first generation of four-strokes all had one thing in common - they were heavy. When you add all of those extra four-stroke parts like an oil sump, valve train, etc., the engines definitely increased in both mass and weight. For example, the original Honda in-line 6 cylinder BF115 weighed in excess of 500 pounds and the Yamaha F200/F225 V6 four-strokes were over 600 pounds. Compare that to a Merc 225 OptiMax of that era that pushed the scales at about 510 pounds. Four-strokes will save you the cost of two-stroke outboard oil, but they do require additional maintenance, like oil and filter changes every 100 hours of use, and some require periodic valve adjustments, which are two expenses that don't impact two-stroke owners.

Four-strokes that dead-head half of their cylinders with every turn of the crankshaft need more cylinder mass to compete with the peppier propshaft sea horses generated by two-stroke powerplants that are firing all of their cylinders with every rotation of the crank. This added displacement also contributes additional mass, driving the weight factor of a four-stroke even higher compared to the two-stroke option. If you are repowering a post 2002 boat, going with a four-stroke repower is a nobrainer.

When considering a new outboard for a pre-2002 vessel, there is a concern regarding which solution will work best, since these boats weren't designed with the requisite buoyancy aft that is needed to keep cockpit and engine well scuppers above the waterline with the added weight on the transom. However, some of the latest next-gen four-strokes are solving the weight loss challenge nicely and might be a perfect fit for your pre-2002 legacy hull.

On the flip side, although two-strokes typically generate the best horsepower-to-weight numbers, outboard engineers who I've talked with agree that the life span of a well maintained four banger is generally longer than that of a two-stroke. Two-strokes require adding a special oil blend to the fuel system via an offline injection tank (at $30 to $40/gallon), plus room to store it somewhere onboard, with the requisite power wires, oil alarms and supply hoses attached to your engine.

Depending on how much oil your two-stroke will consume and how much you buy it for (quart bottles vs 55-gallon drums), two-strokes add to the cost-per-mile operating expenses that might exceed the periodic oil changes of their four-stroke brethren. I am not making a case for either technology being superior to the other, just trying to explain the nuances. I currently own two four-strokes and one two-stroke outboard and I am convinced that each is at the top of its game for its intended purpose.

NEW LIFE
Repowering your boat will definitely breathe new life into it and if you go with the extended five- to six-year warranties offered by some engine manufacturers, you can look forward to many seasons of hassle-free ownership, at least from a propulsion standpoint. One decision that you will need to make is do you stick with the same engine brand manufacturer or not? There are certain cost efficiencies when sticking with a Yamaha/Yamaha, Evinrude/Evinrude, Tohatsu/Tohatsu, etc. repower process. The gauges are likely the same, as are the control cables, fuel hookups, battery and electrical connections, and overall functional compatibility. But this is not always the case, if you are upgrading from an old Yamaha 200 HPDI two-stroke to one of their popular new F200 inline four cylinder four-strokes, it may require a totally different landscape of gauges and controls.

If you stick with an analog F200, you might be good to go, but if you prefer a digital fly-by-wire electric model, then you will be reinventing the wheel, with a lot more cash spent on purchasing additional parts and the labor to install them. Ditto if you are going from a Mercury to a Honda or vice versa; you will probably need to replace all of the aforementioned items and possibly a few things more that weren't mentioned. Some engines like Mercury's new 115 Pro XS high-output four-stroke are capable switch-hitters and can work equally well with either analog or digital gauges.

SPACE AGE CONTROLS
One of the sidebar benefits of repowering is the ability to reinvent the transom of your boat. Boat steering systems are all the rage these days for the big sportfishing machines and their capabilities are simply mind-boggling. SeaStar introduced their Optimus 360 Joystick a while back, and it has been a great success ever since and is also the basis of Evinrude's i-Dock System. I-Dock provides 360-degree maneuvering agility with fingertip control, as the operator easily moves the three-axis joystick docking control to negotiate crowded areas, dock the vessel, or stall the boat over an inshore rip or local wreck.

Smart Cylinders with rudder position sensors allow twin Evinrude E-TEC engines to be controlled independently or in tandem to maneuver the boat sideways, diagonally, forward and backwards, rotate on its axis or even crab-over sideways to accomplish tricky docking maneuvers. The unique BOOST mode provides increased docking power in wind and water current. I actually field tested this system at a local boat show and it works as advertised.

Yamaha's Helm Master uses flexible, streamlined rigging that digitally connects an enhanced binnacle control, a high-definition LCD screen, electronic steering, an electronic ignition panel, a theftdeterrent system and an innovative joystick. Together these components form a true driveby-wire system that responds instantly to your command. Big boats require big power, and big power demands maximum control. Helm Master is compatible with In-Line F200 outboards in twin configurations and 4.2L V6 Offshore and all V8 F350 models in twin, triple or quad configurations. It's calibrated for your specific boat and application, offers second station flexibility, and features user settings you can customize to fit the way you drive.

Mercury also offers a version of this joystick control system for their Verado four-strokes, and the SeaStar Optimus 360 Joystick system is compatible with a variety of engine manufacturers.

NEW BLOOD
As previously mentioned, there are some new and exciting motors currently offered by the various outboard manufacturers that are excellent for repower applications. Yamaha's Offshore Series of 4.2L V6 four-strokes are about 50 pounds lighter than their 3.4L/600-pound first generation counterparts and generate considerably more horsepower torque and punch at the prop with a 25 percent increase in displacement (Remember the mantra for four-strokes: there is no replacement for displacement.).

The latest F175/F200 in-line four-strokes are also excellent repower solutions for the older V6 two-strokes, with just a touch more weight at the transom and better fuel economy. Honda (and Tohatsu) has been selling a bunch of its recently introduced BF250 four-strokes, and Mercury introduced a 350 Verado last year that steps them up into the top competitive tier. The one nuance of the Verado outboards is that they will easily repower an existing Verado installation, but because of the numerous steering, fly-by-wire controls and transom setups required, it is extremely difficult to do a repower on a non-Verado vessel.

Evinrude's new ETEC G2 engines (150 to 300 horsepower) are a step up the two-stroke evolutionary ladder and offer excellent power-to-weight benefits, low maintenance operations and reduced exhaust emissions, with the typical peppy performance expected from this proven combustion process. Evinrudes also have a unique self-winterizing function, which is something for Northeast boaters to take a close look at. Consider the recent trend of winter weather settling in well after the New Year, and the fishing season extending beyond when most anglers have already winterized their powerplants. Evinrude's system can put you back in the action with the simple push of a button.

Suzuki recently introduced a new DF350A V6 outboard that will be very popular with the offshore crowd. At 350 horsepower, this V6 four-stroke is the largest and most powerful outboard that Suzuki has built to date. In development for more than three years, it represents a significant milestone in engineering, design and performance. With a 12:1 compression ratio (the highest of any current production outboard), a dual prop drive, 2.29:1 two-stage lower gear ratio, twin fuel injectors for each cylinder, 24-valve DOHC setup and a huge 4.4L displacement that tips the scales at 727 pounds in the XL version, this girl is a beast and is ready to take your 35- or 40-something battlewagon offshore. The DF350A can be mounted 27 inches on center, so it will fit on more transoms, and take up less space in twin, triple and quad installations.

REAL WORLD REPOWER
One of my fellow saltwater guides, Capt. Mike Modica of East Quogue, NY "Ship of Fools" recently replaced his burned out Yamaha 200 HPDIs at 1,530 hours (right on schedule) on his Grady-White 28 Sailfish with a pair of the svelte F200s. The entire project set him back just north of $42,000 working with a local dealer and he was able to reuse some of his old instrumentation and controls. He went from 1.2 mpg at cruising speed to 1.8 mpg making basically the same headway. As expected, he must run his new F200 four-strokes at about 300 rpm more to get the same cruising speeds as the older HPDIs (He also has four less cylinders to work with.) but the engines are quieter, smooth and produce none of the dreaded blue cloud that carbureted two-strokes were infamous for when idling at dockside or in a fluke or bass rip.

So what have I learned from all of my own real world experimentation? Upgrading to newer engines improved reliability, performance, speed and fuel economy as predicted. But the added weight of different types of fresh power also caused some center of gravity changes that affected my boat's self-bailing abilities and required some minor adjustments to correct the problem.

In summary, it certainly pays to do your research when considering an upgrade to new outboard power, and once you realize that there are multiple considerations like fuel efficiency, transom weight, cost of ownership, maintenance schedules, parts compatibility, changes to top end and cruising speeds and overall longevity, you will be in the best position to make the right move.

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You love your boat. It has taken years to get it outfitted and made as fishing efficient as possible, but your outboards are getting long on hours and you need to know those engines will get you home from the blue water trouble free.

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1. Upgrade to new technology

It's only natural that all those modern technologies we have today, including digital controls, power steering, data displays and digital instrumentation, were not featured on the boat a decade ago. Hence, instead of buying a new boat, you can look for a decent repower job for the vessel to enjoy such new features.

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top 4 reasons to repower your boat with a new outboard

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Top 4 Reasons to Repower Your Boat with a New Outboard

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It's only natural that all those modern technologies we have today, including digital controls, power steering, data displays and digital instrumentation, were not featured on the boat a decade ago. Hence, instead of buying a new boat, you can look for a decent repower job for the vessel to enjoy such new features.

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Reasons to Repower Your Boat With an Outboard Engine

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In this article, Charles Plueddeman, longtime contributing editor, lays out some reasons for, and benefits of, repowering your outboard powered boat.

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Forget slow horses and fast women. Ask any boat broker what makes a boater broke, and they'll tell you in six succinct words: "Spending good money on bad motors."

In my yacht-selling days I've seen engines catch fire, cook themselves, conk out at critical moments or resolutely refuse to start.

They've belched smoke in myriad hues of white, black and blue, and oozed oil like a pizza addict's pores.

In one memorable gearbox failure, the reverse mechanism failed just as the yacht entered its marina pen, and the bow struck the concrete walkway at four knots. Try selling a boat that's suddenly 60 centimetres shorter to buyers who are lying dazed across the deck.

No matter how well it sails or presents, there's no greater passion-killer for resale value than mechanical mayhem.

The salesman sees fear of the unknown in the buyer's eyes. They see the buyer's beloved leaping over the lifelines and beating a hasty retreat towards their car.

Some owners don't see anything, however. Whether love is blind or stubbornness is plain dumb, they persevere well past the point of no financial return.

One owner I know spent $1500 investigating an overheating problem only days after buying his yacht. On the delivery trip home, the gearbox disintegrated, necessitating a police tow and another $8000 investment.

The parts were presumably delivered by stage coach and, judging from the bill, were installed by a neurosurgeon at the Hilton. Then came alternator issues, injector dramas, more overheating problems and finally a rebuild.

When advised to cut his losses and install a new motor, he slammed his fist and cried, "I've spent 20 grand on this $#@ motor, I'm not giving up now!".

That's the dilemma, I guess. At what stage do you draw the lines between a repair, a rebuild and a full repower?

Any money spent may, one day, save the boat and lives, because marine engines must, above all, be reliable, especially when the crew's ability to deal with breakdowns is limited.

A well-maintained diesel should run for at least 8000 hours without major overhaul and, since the average recreational sailor logs only 100 to 200 hours per year, it should, theoretically, last the lifetime of the boat.

If small problems aren't addressed, though, they generally turn into big problems.

Consider the conditions in which yacht motors operate - hot, damp, cramped with salty bilges, intermittent use and irregular maintenance. What they really need - cool and dry air - is rarely what they get. Nor do they have the benefit of long running times, as a powerboat engine may.

Repairs will keep you going, but eventually weak links appear in the chain. When it comes to rebuilding, parts can be expensive and hard to find, plus you need a skilled mechanic to do the job.

Rarely are the older, raw-water cooled engines suitable for rebuilding as the internal water passages in the block and head are corroded beyond salvation.

Ultimately, a rebuild can cost money that's better invested on new technology. As a rule of thumb, don't spend more than 40 per cent of the full cost of a replacement.

You can sell or trade your old engine if it hasn't totally given up the ghost, but it needs to also be kept in mind that the outlay on a new installation will rarely be offset by a rise in resale value. You do it because you want to enjoy trouble-free use of your boat and to limit future expense.

And what price do you put on instant starting, increased reliability, quieter running, lower emissions, efficient charging, superior performance and fuel economy, longer service intervals and warranty support?

PLANNING AHEAD

Once you've decided to take the plunge, it's not all plain sailing. There's the small matter of removing the old donk and finding a new motor that fits.

The popular trend is to install more powerful engines in sailboats. It's possible because newer motors are lighter and more compact, but whether it's necessary is another matter.

A displacement hull's speed is governed by waterline length, and no amount of extra power will help it breach the trough between bow and stern waves. The rough formula is 1.3 times the square root of waterline length (in feet), so a 36-footer is good for about 7.8 knots.

Too much power is bad news as subsequent light loading of the engine will result in cylinder glazing and high oil consumption. Ideally, you want to hit hull speed at 80 per cent throttle as it will ensure the engine is being worked reasonably hard.

The additional 20 per cent is there for adverse wind and tidal conditions.

If you go to the trouble of fitting a new shaft, then give some thought to mating it with the optimum propeller. Folding propellers have advanced eons in design, combining maximum thrust with minimal resistance.

OPTIMUM PROPS

Also, your existing prop may need to be re-pitched if you decide to keep it. Pitch refers to the distance a propeller travels forward through one revolution - higher pitch means lower revs per minute, and vice versa, so the quest is to reach your recommended Wide Open Throttle (WOT) operating range.

Propeller shaft rotation has changed over the years. Motors from the 1980s and early '90s tended to have left-hand rotation when in forward, whereas the majority of modern diesels have right-hand rotation.

Many a boat has been repowered - only to find it goes very well in reverse

Many a boat has been repowered - only to find it goes very well in reverse.

Saildrives were introduced by Volvo Penta some 40 years ago and they can be exchanged with relative ease. It's also possible to do a retrofit installation, which you'd consider in the case of a difficult shaft installation ... a vee drive, for example.

A shipwright will have to modify the hull with a suitable fibreglass bed, but on the plus side is the fact that saildrives are well-priced and have good service history.

If the naval architect has factored engine removal into the equation, it's generally a case of lifting the block out through the companionway; otherwise a hatch will have to be cut in the cockpit floor, or the motor disassembled.

The mounts and installation requirements are likely to have changed, even when swapping like-for-like in terms of engine brands. There's nothing that can't be fixed, it just adds cost and complexity.

A common mistake is to duplicate the old exhaust system, which results in a new engine being installed to an outdated standard. Again, the replacement may be more compact and have a low-slung exhaust.

The system must be designed and installed to prevent saltwater from back-flooding the engine. Back-flooding (when water enters the cylinders) can occur when sailing with the engine off in a following sea, or when the boat is pitching or heeling.

Ventilation is another consideration, as many new high-speed engines use more air, especially those with turbos. That means larger vents are needed.

While you're at it, compare the location of service points between old and new. It's useless if the oil filter, for example, is mounted in a different location to the original and difficult to reach.

Your old, sediment-trap fuel filter is best thrown away, along with the lines, and replaced with an element-type primary filter. It pays to flush and clean the fuel tanks as well, since modern diesels have finer tolerances in the fuel system.

Older motors tended to have belt-drive mountings for fridge compressors, bilge pumps and the like. It's unlikely you'll find these today, though new flywheel generator options, such as the Yanmar KMG65 system, allow better charging systems to be embraced.

The alternator capacity and type of voltage regulation is likely to have changed, too.

New engines deliver 12 volts, while some older systems were 24-volt.

Repowering often means switching from a mechanically-governed engine to one with electronic management. Electronic diesel control came into vogue around 1995 and technology like Volvo Penta's EVC system makes the installation of engines, controls and instruments far simpler thanks to the use of plug-in connectors.

It brings benefits such as electronic throttles, smart gauges with full trip computer functions and, through NMEA 2000 interfacing, the ability to display data on a chartplotter.

When you really think about it, hull design and construction have somewhat stagnated, whereas new motors are significantly evolved. If you reckon there's life in that old seadog of yours, then you can teach it new tricks.

CASE STUDIES

CSY44 Beaujolais

Brit Roger Dance found his dream yacht in the US back in 2006 and immediately began readying it for the South Pacific cruise of a lifetime.

His main concern was the original Perkins 4-104 62hp diesel that had clocked well over 9000 hours.

He spent $US2000 with two mechanics who reckoned they could sort out the running issues before an independent assessor advised him that it probably wouldn't last more than a year or two.

In went a new Yanmar 4JH4-TE 75hp Turbo and new gearbox and Roger chose a new 3-blade Maxprop propeller.

The exhaust expanded from 50mm to 75mm, but it was a simple case of widening the stern fitting. Roger fitted an exhaust flapper to ensure that no water would ingress the engine.

From haul-out to splash was seven days, even allowing for the engine room to be repainted.

"I can trust the engine totally, it starts first time, every time," Roger, who now lives in northern NSW, said. "It's done 2500 hours already without missing a beat."

Spencer 42 Supertramp

One of Victoria's glamour racing yachts in its heyday, this 1977-vintage design was looking every bit the timber tramp when Morrie Morgan bought it two years ago.

The original Yanmar 2GM 20hp diesel had seized, so the boat sat and slowly deteriorated. Buyers were nervous about doing a new motor install as it had a potentially troublesome vee drive, and there was the risk of over-capitalising.

Morrie, a professional skipper, saw the potential and tackled the task himself. In the words of the Supertramp song, he was "bloody-well right!".

"I took the vee drive out and had it rebuilt ($1200) then dismantled the engine box to get access to the motor," Morrie said. "It slid straight out and we lifted it using a travel-lift crane."

The bearers had to be adjusted for the shiny Yanmar 3JHSE 40hp donk that was going in, so Morgan had them sandblasted and epoxy-painted. The installation ran smoothly, for a total outlay of $12,500.

"I have to adjust the pitch of the prop because it's over-revving, but otherwise it couldn't have been easier."

Farr 40 Aurora

Under the ownership of Jim and Mary Holley, Aurora was baptised in the storm-torn 1998 Sydney Hobart and has completed every race since ... the only yacht to do so.

It says something about their skill and tenacity, but even more about how thoroughly they prepare a vessel that dates back to 1983 as Witchcraft II.

Farr 40s were originally configured with shafts, the engine residing near the mast. The previous owner moved it back beneath the companionway and installed a saildrive, which made the replacement easier.

Jim was returning from Hobart when, off Eden, the old motor began making rasping noises. He shut it down and was forced to sail for five days back to his berth on Newcastle Harbour.

A rebuild proved to be merely a band-aid, so in 2005 he commissioned Endeavour Marine to install a new 40hp Volvo Penta.

After years of having a shonky donk, he says it's "just wonderful" to start and has remained trouble-free.

"Two cans of 'Start Ya Bastard' spray were essential equipment before we went to sea, but not anymore," Jim said.

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Forget slow horses and fast women. Ask any boat broker what makes a boater broke, and they'll tell you in six succinct words: "Spending good money on bad motors." In my yacht-selling days I've seen engines catch fire, cook themselves, conk out at critical moments or resolutely refuse to start.