posted 09-04-2013 01:44 PM ET (US)        

The ENERTIA ECO is constructed from a special alloy of steel, often referred to as Unobtainium by boaters or as X7 by Brunswick publicists. At one time Brunswick indicated this alloy was going to be patented, but, as far as I know, there is no patent. Brunswick publicists now refer to it as a proprietary alloy of stainless steel. One of the characteristics of the alloy has been described as an ability to flex under load.

The ENERTIA ECO is said to be made in 16-inch diameter. Such a large diameter may limit its application. I suspect that the newer gear case designs used by Brunswick on their VERADO-branded outboard engines will be large enough to accommodate a 16-inch-diameter propeller, but I wonder if outboard engines made by other manufacturers can swing such a large diameter propeller.

The blade geometry is described as having a high, progressive rake. Having a propeller with blades of 16-inch diameter and a high, progressive rake is claimed to be made possible only through the use of Unobtanium (X7) alloy. The precise reasons why the use of 16-inch diameter and high, progressive rake blades is exclusively possible with only this alloy of steel is not clearly explained by Brunswick.

The ENERTIA ECO propellers will be available in pitches of 17, 19, 21, and 23-inches in both right-hand and left-hand rotations.

Brunswick further claims that use of the ENERTIA ECO propeller will produce an improvement in fuel economy of 10-percent at cruising speeds. It is not clear to me what the improvement in fuel economy of 10-percent is measured against. I am sure there is some propeller which, if compared to the ENERTIAL ECO, will allow for the ENERTIA ECO to have a 10-percent improvement.

posted 09-17-2013 11:23 AM ET (US)            

September 17, 2013

FOR IMMEDIATE RELEASE

For information contact:

Lucas Lauderback

Mercury Marine

lucas.lauderback@mercmarine.com

920-929-5980

Mercury Marine introduces Enertia ECO fuel-saving propeller

FOND DU LAC, Wis. – Addressing the related topics of increasing fuel costs and environmental stewardship, Mercury Marine is pleased to introduce the new Enertia ECO propeller today at IBEX in Louisville, Ky.

The Mercury Enertia ECO was specifically designed for high-horsepower outboard-powered boats, offering boaters a 10 percent increase in fuel economy at cruising speeds while also living up to the performance and reliability standards inherent with all Mercury propellers.

To maximize the fuel economy improvement provided by the Enertia ECO, Mercury Marine engineers designed a new propeller with a broad 16-inch diameter, large blade area and a high progressive rake, a combination made possible only through using Mercury’s proprietary X7 stainless steel alloy. While the Enertia ECO design results in reduced hull drag through increased bow lift at cruising speeds, it still matches the performance of other Mercury propellers such as the Enertia and Revolution 4.

“Mercury Marine already produces fuel-efficient engines, as well as driver aids such as the ECO Screen display,” said Jared Reichenberger, brand manager for Mercury Propellers. “As marina gasoline prices have continued to rise, however, customers are increasingly focused on fuel economy. We realized an appreciable fuel economy gain could be found in the design of the propeller itself.”

While boaters continue to demand the best acceleration and top speed, there is also a growing requirement for efficiency and fuel economy at cruising speeds where a vast majority of their operating time is spent.

At cruising speeds, the Enertia ECO posts a minimum of 10 percent fuel economy gain compared to Mercury’s already-efficient line of offshore propellers. This gain translates to dollars as the typical offshore boater averages nearly 100 hours on the water each year. At today’s gas prices, this propeller alone will save that boater more than $550 per year, which translates to more than $5,500 over 10 years.

In addition to saving money, the Enertia ECO provides additional range from each tank of fuel. Whether they are pursuing fish farther from shore, or simply cruising longer between fill-ups, boaters can now significantly extend their range with a simple propeller change.

These savings will be available to consumers beginning in January 2014 in right- and left-hand rotation across four pitches: 17, 19, 21 and 23 inches. All feature a 16-inch diameter.

More information is available at mercurymarine.com.

posted 09-18-2013 02:54 PM ET (US)         

It is widely known that Mercury reduced the Verado 3-star rating to a (2.90) 2-star rating to improve fuel economy on these engines, 150-350 HP. I am wondering if this new prop could now allow Verado the same 2-star better fuel economy and a return to the 3-star rating? Note that the press release says they are designed for high HP outboard boats, so the Verado applications should be considerable.

posted 09-18-2013 03:03 PM ET (US)            

There were (and are) those simple folks who think this means it *will* offer 10 percent greater speed and fuel economy, but that does not mean it is true.

There may well be some application where speed and fuel economy is improved by using an Enertia Propeller, especially if the propeller being replaced is not well suited to the application, but there is no guarantee.

On my 25 foot Whaler with twin 150 HP mercury outboards, going from a pair of 19" MIRAGEplus prop to a pair of 19" Enertias resulted in lower top speed and reduced fuel economy.

posted 09-18-2013 04:07 PM ET (US)         

In my case, with considerable testing, the Revoution-4 props were 5 MPH faster than Mirage Plus, achieved mainly because of how they completely lift my relatively light hull out of the water over 50 MPH. They are literally too much prop, too much overall hull lift, for the HP/weight ratio. Laser II's were also faster than Mirage Plus. So I would guess the Enertias would be faster also.

posted 09-18-2013 09:18 PM ET (US)            

What 150 HP outboards does Mercury sell today that are better than that?

BTW, I have also tested two different sets of Revolution 4 propellers on my boat and neither offered as much speed or as much fuel economy as my MIRAGEplus propellers. The Rev 4s are not know for top speed. They are know for load carrying capacity and grip, especially at slower speeds.

posted 09-29-2013 11:36 AM ET (US)            

Mercury Marine ENERTIA ECO Propeller

posted 09-29-2013 11:52 AM ET (US)            

Twist does not suggest progressive pitch, it suggests large diameter.

posted 09-30-2013 10:28 AM ET (US)            

The only indication of thickness one can get from this photo is the trailing edge of the blade on the left side and that may, or may not be, how it appears in real life. The edge of the image in rather pixelated so who knows how thick that trailing edge really is.

posted 09-30-2013 11:29 AM ET (US)            

We have seen that developments by OMC or Evinrude have been widely copied by others, most notably Yamaha, who made just about exact copies of some OMC engines, and this is a reasonable basis that innovations by Evinrude might be copied by others. In the case of Chrysler and its engines or propellers, I do not recall anyone citing them as innovative or copying them, so I can understand how you might use them as a ridiculous comparison. But Evinrude has been innovative, and it is not out of the realm of possibility that some element of the REBEL propeller that engenders its improved fuel economy might be employed in the ENERTIA ECO. To suggest that this is nonsense seems to me to be without any basis.

There seems to be some sort of mythology that only Mercury can accomplish innovation in propeller design or manufacturing, but I do not see any basis to support that belief system. I will acknowledge that Mercury makes many models of propellers, so just by numbers alone they would be likely to have hit upon something useful. My suggestion that the ENERTIA ECO may have copied some feature of the Evinrude REBEL is just an extension of my belief that Mercury does not possess any sort of exclusivity on propeller design or innovation.

Tom--I very much like your observation regarding where the blade might be thinner, and that at the very edge it is simple to get a thin blade, whereas at the root it is much more difficult. That makes perfect sense.

posted 09-30-2013 12:12 PM ET (US)            

--the REBEL has proved in real world testing to improve fuel economy compared to the MIRAGE; the claim is the ENERTIA ECO will do the same. Therefore it is reasonable to conjecture that perhaps the ENERTIA ECO incorporates some of the same designs found in the REBEL because it claims to be able to accomplish the same results;

--there is a general similarity in appearance.

On the other hand your conjecture that the REBEL is a copy of some Chrysler propeller is unsupported by any basis. I think you made it as an attempt to ridicule my conjecture.

It would be more effective for you to make some argument about why there is unlikely to be any similarity in the ENERTIA ECO and the REBEL if you want to dispel my conjecture. Otherwise you need to explain how you can dismiss it out of hand, without any reasonable basis. Perhaps it reflects a bias or belief system you hold that only Mercury can be innovative.

posted 09-30-2013 12:50 PM ET (US)            

Compare and contrast with photos here:

posted 09-30-2013 01:16 PM ET (US)            

Let us test the opposite of my theory: this would suggest that there is nothing remotely similar about the ENERTIA ECO and REBEL, and that the method of improving fuel economy in the REBEL is completely different and unrelated to the method used in the ENERTIA ECO. That seems like a far more unreasonable speculation, yet that is what one must believe if one is to dismiss my speculation as nonsense. Common sense tells us that it is much more reasonable to believe that the improvement in fuel economy in the two propellers comes from similar methods.

On another topic, much less speculative, I note that the diameter of the ENERTIA ECO is very large, 16-inches, and all models, regardless of pitch, are made in this diameter. This method is in contrast to the normal approach to propeller design where the diameter and pitch seem to vary, with the general notion that the diameter tends to decrease when the pitch increases. In the past, there has even been a careful analysis of the ratio of pitch and diameter which suggested they were important to create the most efficiency. It was even argued, by extension, that because of this the gear ratio of the outboard engine must be carefully selected to be a certain value--and, as usual, only the Mercury gear cases had the right ratio.

With the diameter remaining constant at 16-inches, the pitch-diameter ratio of the ENERTIA ECO changes with each propeller. This seems to diminish the credibility of the theory that only certain pitch-diameter ratios could be efficient.

posted 09-30-2013 01:48 PM ET (US)            

Just because the REBEL got the best fuel economy on in your extremely limited test leads you to the conclusion that any propeller that improves fuel economy must be a copy of the REBEL?

The method in which the Enertia gains fuel economy is completely different from the REBEL. The ECO to come does it with X7 alloy which allows for thinner blades and more radical prop rake and also uses a much large diameter which the REBEL does not.

posted 09-30-2013 02:32 PM ET (US)            

The use of Unobtanianium was previously cited as leading to more speed. It appears to now be conjectured to cause more fuel economy. If it does both at once, why do we need two models of ENERTIA, one for speed, one for economy? This seems to rule out the notion that use of Unobtainium causes better fuel economy. If it did both at once, we would only need one model of ENERTIA.

My test may be limited but it is a test. So far we have no tests of ENERTIA ECO. It is hard to refute one actual test but accept no tests in preference.

The blades of the ENERTIA ECO do not appear to have a radical rake.

I have now refuted your arguments four times:

--there is not "a much larger diameter" in the ENERTIA ECO

--there is a paradox in having two models of ENERTIA if Unobtainium is the key to fuel economy;

--accepting unproved claims over a proven claim is not rational;

--the blade design of the ENERTIA ECO does not appear to have much rake, at least not in the pitch model shown in the image.

I would be glad to hear some rational argument in which you can preclude the possibility that the Mercury ENERTIA ECO has nothing similar to the Evinrude REBEL in the manner in which it improves fuel economy.

Do you have any first-hand experience in using an ENERTIA ECO? Have you seen one yourself? Have you seen the higher pitch versions?

posted 09-30-2013 02:44 PM ET (US)            

I would call that "a much larger diameter".

The alloy is different and I contend the material, blade shape, the root of the blades, rake, and diffuser ring is vastly different from the REBEL.

You have made no line to connect the ECO to the REBEL accept the REBEL improved fuel economy on your boat in a limited nonscientific test.

posted 09-30-2013 02:50 PM ET (US)            

Check out the pictures side by side. It is a dead ringer.

posted 09-30-2013 02:56 PM ET (US)            

Check out the pictures side by side. It is a dead ringer.

posted 09-30-2013 03:28 PM ET (US)            

To clarify, Unobtainium is a structural engineer's mocking description of the material required to perform impossible structural tasks as designed by an architect.

Architect: I've got low headroom, so we need to this 30 foot span done with a 6" wideflange.

Engineer: Is that so? You want me to spec it as Unobtainium?

Its a magical material, one that doesn't exist. Thats the "un" prefix.

Mercury's material actual does exist. It has been obtained. They call it X7 and I suppose its a proprietary alloy of some sort, whose attributes the massive team of Mercury propellor R&D engineers liked for this application.

posted 09-30-2013 05:20 PM ET (US)            

Now what do we call the proprietary alloy that is used to make the BRP REBEL? Any suggestions? How about Evinrudium?

posted 09-30-2013 05:26 PM ET (US)            

--the REBEL delivered better fuel economy in my controlled and scientific testing;

posted 10-02-2013 02:28 PM ET (US)            

--does not have the Elephant Ear blade shape seen in the original ENERTIA

--does not have highly skewed blades like the original ENERTIA

--does have a rather long exhaust tube or snout, like the original ENERTIA

I think it is quite reasonable to say that the ECO ENERTIA looks much more like the BRP REBEL than it looks like the original ENERTIA. It is clearly not some evolutionary or incremental change from the original ENERTIA.

The two aspects of this new ECO ENERTIA series that are distinctly different than all previous propeller series from Brunswick are

--the constant diameter, regardless of pitch, and

--the really very large diameter, just about the biggest possible diameter than can fit in an outboard gear case

posted 10-02-2013 06:31 PM ET (US)            

quote:

---

The two aspects of this new ECO ENERTIA series that are distinctly different than all previous propeller series from Brunswick are

--the constant diameter, regardless of pitch...

---

No, that is not true at all. Several models of Mercury propellers have a constant diameter regardless of their pitch. Off the top of my head I can think of the

- Revolution 4 @ 14-5/8"

- VenSura (fka Offshore) @ 14"

- Tempest Plus @ 14-5/8"

- Fury @ 14"

posted 10-03-2013 09:11 AM ET (US)            

Mr. Clark brings up an interesting point about the Suzuki's using larger diameter props for sometime. They do this to take advantage of the lower gear ratio but they run into a serious problem and that is the lack of top end speed. You almost never see a go fast or triple/quad Suzuki 300hp engines on a boat because you are limited to below 60mph (give or take) because you would need to swing a 34pitch prop with their gear ratio to get above it.

My theory is that the new ECO prop is designed for midrange performance and lower. By focusing on this performance aspect alone they can improve fuel economy.

posted 10-08-2013 07:38 AM ET (US)            

I don't recall the claim of Brunswick's publicists that X7 was stronger, or that it was 30-percent stronger than some other kind of steel. Where are these claims made?

posted 10-08-2013 08:41 AM ET (US)            

Mercury Alloys

X7 Alloy
A revolutionary proprietary alloy from Mercury that shatters the rules of propeller design.

30-percent stronger than conventional stainless steel

Four times more durable than conventional stainless steel

posted 10-08-2013 11:00 PM ET (US)            

As for prices, the REVOLUTION4 sells at a deep-deep-discount price $449 and the ENERTIA sells for exactly the same price from the same dealer. The MIRAGEplus, a propeller that LHG loves to dismiss as a terrible propeller, one of the worst choices available from Mercury, sells for $399, No wonder the price is $50 less than the state-of-the-art ENERTIA made from the revolutionary new steel invented by Brunswick, as we have been hearing about how much of a dog the MIRAGEplus is supposed to be.

posted 10-09-2013 01:07 AM ET (US)         

Like the REVOLUTION4, the MIRAGE was developed as a sterndrive propeller, and with outboards is recommend for heavy boats with high power. For those hulls that need 25=pitch and higher, they are what you want, since the REVOLUTION4 are only made up to 23-pitch and the ENERTIA up to 22-pitch. They don't hold particularly well at higher mounting heights in offshore seas. I don't have an application where they make sense for me, and did not perform well on my Outrage 25 with twin 200 EFI Mercury engines. On the contrary, Tom Clark says they are the best for his 25 Revenge with transom mounted 150-HP engines.

The REVOLUTION4, Tempest Plus, Trophy Plus, Fury, Bravo I, and ENERTIA are all more modern designs and better performing propellerss for the designated applications, which includes offshore center consoles like I have. If anybody checks Boston Whaler's performance reports on their new boats that use 135-HP or more, you will find the Enertia selected almost universally. That's a pretty strong endorsement that it is a superior propeller for the kind of hulls we run. They must know something, and are not showing the MIRAGEplus ever since the ENERTIA came out. On the larger models they are using the REVOLUTION4.

posted 10-09-2013 09:06 AM ET (US)            

It looks to me like the ENERTIA ECO has more in common with the REBEL than the MIRAGEplus , and that is why it seems reasonable to speculate that the ENERTIA ECO is just Brunswick's copy of the BRP's REBEL. After all, BRP has the benefit of 20-years of time to make an improvement. It would be completely expected that in 20-years of testing and development there could be some refinement in propeller design that permits BRP to make a better propeller than a 20-year-old propeller design. Brunswick probably saw they were getting behind the curve with their MIRAGE design, and they updated it with the ENERTIA ECO, based on the REBEL. This is a completely logical conclusion. Brunswick probably bought a REBEL, tested it, saw how well it worked, and put their supercomputers and staff of 50 engineers to work on making something equal or better.

Thanks to LHG for the short presentation on the history and application of all Mercury propellers. I am not at all surprised by LHG's initial premise: "...within any propeller category, Mercury propellers are the best you can buy..." but my testing has not shown that to be true. I found that BRP propellers worked better on my boat. BRP propellers have been developed to work on BRP engines, where they operate behind BRP gear case designs. That is the situation I have on my boat.

Let me explain a bit about my propeller testing and how it has differed from LHG's. I have a single engine boat, so it is much simpler for me to test propellers. I have an open mind about propellers, so I have tested propellers from several manufacturers. I have tested more than a dozen propellers made by four manufacturers. In contrast, I believe that LHG has only tested Mercury-brand propellers, and has perhaps tested a total of four different types on his twin engine boat. This is understandable, because testing on twin engine boats makes it much harder to test propellers, and if you limit yourself to one brand, you limit the choices.

Now a person who only tests Mercury-brand propellers is going to find that the best propeller he has tested is a Mercury-brand propeller. I don't think you can escape that outcome with the testing criterion set up by LHG. Also, I don't think a test of perhaps four different propellers is sufficiently comprehensive. There are many propellers available. Heck, even limiting yourself to the Mercury-branded Brunswick propellers gives a lot of choices.

I don't know that citing the use of Mercury-brand propellers on Boston Whaler boats is much of an endorsement. It would not make any sense for Brunswick to use anything other than Brunswick propellers on their Brunswick boats. Also, if Brunswick were to use their most expensive propellers on some of their most expensive boats, this would not be much of a shock. I really do not find there is any really independent data that can be taken from the practices of Brunswick with regard to what propeller is the best choice. It is likely that Boston Whaler propeller selection will be the best choice available from Mercury-brand Brunswick propellers. That seems quite certain.

What I have found from my propeller testing is every boat, motor, and propeller combination works differently, and there is no certainty that a particular brand propeller will work exactly the same in every application and be the best. If I may give a bit of a simplistic explanation--a sort of corollary to LHG's assessment of the propeller application process--I say this: a propeller operates behind a gear case. There are different gear case designs among outboard engines, even engines of the same brand. The flow of water around the gear case will be different with different designs. This affects the propeller operation because the propeller is downstream of the gear case. In a similar way, the gear case is downstream of the hull. The water flowing off the hull is different for every boat. The propeller operates in a variable environment, created by the water flow off the hull, over the gear case, and into the propeller. Further modifying the propeller environment is the outboard engine mounting height and trim. All of these effect the propeller environment on a boat. Because this environment is so variable, the performance obtained with a particular propeller is subject to a lot of variation from boat to boat.

Because there is so much variation from boat to boat, the claim that one particular propeller, in this case the Mercury-brand ENERTIA ECO propeller, can improve fuel economy in some applications is not much of a claim. You could probably make this claim about any propeller because there is some boat out there where that propeller would make an improvement. Now, if the claim is that the ENERTIA ECO will always make a ten-percent improvement, that is quite a mighty claim.

posted 10-09-2013 10:28 AM ET (US)            

According his logic, any product that improves fuel economy has to be a copy of the REBEL Prop.

Even though we have already reviewed is, we will have to go back to it again.

1.) The blades are shaped differently.
2.) The material of the prop is different.
3.) The blade rake is different.
4.) The diameter is completely different.

19 pitch ECO is 3/4 inch larger than the 19 REBEL.
21pitch ECO is 1 inch larger in diameter vs 21 REBEL.
23pitch ECO is 1.25 inch larger in diameter vs 23 REBEL.

And yet in spite of all of the FACTS, we continue with this nonsense.

posted 10-09-2013 03:40 PM ET (US)            

quote:

---

Don't let facts get in the way.
According his logic, any product that improves fuel economy has to be a copy of the REBEL Prop.

---

I am afraid I do NOT make that generalization. I simply observed the following sequence of events:

--Mercury produces the MIRAGE, perhaps 20 years ago; it is a wildly successful propeller, perhaps the most popular three-blade propeller of the last two decades, in spite of the negative remarks about it by LHG.

--BRP produces the REBEL, which comes out after the MIRAGE.

ASiDE: At this point it has been commented that the REBEL appears to use some of the same design elements of the MIRAGE. Now, when this suggestion is made, no one says it is nonsense. There is no fury, no rage, no indignation, no accusations of nonsense.

--Mercury comes out with the ENERTIA ECO.

--I suggest that the ENERTIA ECO may use some of the design elements in the REBEL. I suggest this because the REBEL improves on the fuel economy of the MIRAGE, and this is the claim to fame of the ENERTIA ECO.

posted 10-09-2013 04:21 PM ET (US)            

My participation in this thread had nothing to do with the differences or similarities between the Rebel and the Enertia-Eco. My participation was merely to call Jim to task for the anti-Mercury FUD he was spreading. Mercury Marine's outboard motor line meets U.S. EPA regulations, but Jim continues to try to spread fear, uncertainty, and doubt about the entire motor line, and even about Mercury Marine's parent company Brunswick, by repeatedly pointing out (in very unflattering terms) that the Verado motor line is only two-star-rated rather than three-star-rated. Mercury Marine is at least as green as it is required to be in the U.S., and I sincerely doubt that Jim can demonstrate that any other outboard manufacturer is greener than Mercury Marine in the U.S.

posted 10-09-2013 10:19 PM ET (US)            

There is nothing about my statement regarding the basis on which the non-conforming VERADO two-star engines are sold. That is not FUD. It is just the truth. You should recall that it was in a discussion that I began on that topic that we were able to learn in detail the actual variance from compliance that exists in the VERADO engines, and to estimate how much fleet averaging was going to be needed. This was a very factual and revealing discussion, and it is the only discussion of its kind you can find anywhere on any boating forum. I think it was a significant achievement to get to the details of the VERADO non-compliance and the amount of fleet averaging needed to permit them to be sold. But we are getting off the topic.

posted 10-10-2013 07:43 AM ET (US)         

I agree with what Jim said (and your sarcasm Jim) about prop testing- the only way to prove better fuel economy due to a prop design is to test it, with the only variable in the test being the prop. Same boat, engine, engine mounting height, boat load, wind, etc.

Show us an independent test with these parameters and numerous props from numerous manufacturers tested on numerous boats and numerous engines and you have backed up your fuel economy claim.

Or at least tell us what testing was done to make whatever claim you are making?

With all the variables, I doubt anyone can make a prop that will improve fuel economy 10% on all boats, on all engines, at all speeds?

Manufacturers all make claims about their products that if worded correctly may be true. They quite often make claims that are not true, but also are difficult to prove true or untrue. They are like politicians or anyone selling anything.

Brunswick are going to sell Brunswick boats with Brunswick motors and Brunswick props, why would they ever sell anything else? They will sell us their best product, but that isn't necessarily the best product available. Even for their own products.

Don

posted 10-10-2013 08:47 AM ET (US)            

The REBEL is round ear prop based off of the MIRAGE. They are large round ear props. Comparing them side by side, you can clearly see this. I dont think many with argue this.

The Enertia ECO looks nothing like a MIRAGE or REBEL at all. It looks like it was based off the of FURY as it has almost a straight trailing blade edge.

It looks nothing like a large round ear prop. These are the FACTS.

1.) The blades are shaped differently.
2.) The material of the prop is different.
3.) The blade rake is different.
4.) The diameter is completely different.
5.) The trailing blade edge is completely different.

posted 10-10-2013 09:05 AM ET (US)            

The FUD also includes trudging up the Verado emissions discussion in an attempt to discredit an unrelated propeller. And suggesting that the entire Brunswick corporation is "goofy" and "hilarious" based on some advertising puffery by just one of its divisions, Mercury Marine.

Finally, Jim, your argument about a boat powered by triple Verado 300s or 350s presents another logical fallacy, reductio ad absurdum. Do you really expect us to believe that the new Enertia-Eco propeller will only be used in large, triple-engine installations?

posted 10-10-2013 01:52 PM ET (US)            

quote:

---

I am shocked this nonsense continues.

---

posted 10-10-2013 02:01 PM ET (US)            

This situation with the VERADO is just like FORD meeting MPG fleet minimum. The FORD truck Kevin is driving could not be sold if FORD only made that truck. It is only by getting a lot of young kids who cannot afford to buy a car bigger than a Focus that FORD pumps up its fleet MPG to the point where a few wealthy folks can drive around town in a gas-guzzling FORD super-duty SUV.

posted 10-10-2013 02:11 PM ET (US)            

quote:

---

ECO meaining economy.

---

Exactly as I said. See my initial article:

"...one can infer that the "ECO" in the model name is suggestive of "economical"..."

That is the engineer talking. These goofy publicists turned "economy" into "green" and planet-aving ecology.

posted 10-10-2013 03:02 PM ET (US)            

Regardless, the fuel savings claims by Mercury are nothing more than marketing hyperbole. Sort of like Evinrude's claim that its E-Tec 250 and 300 horsepower motors have "[m]ore displacement, more torque, more top-end than anything in the V-6 class."

While the Enertia-Eco may provide improved fuel economy over some other Mercury propellers in certain conditions on certain boats, I suspect that there are just as many, if not more, situations where it would not provide improved fuel economy. To me, it appears to be just another propeller.

posted 10-10-2013 06:41 PM ET (US)            

Perhaps when Tom Clark has an ENERTIA ECO he can take a few images of it in overhead and profile, and we can then compare the ENERTIA ECO to the MIRAGE and ENERTIA.

We will have to wait at least three or four months. The ENERTIA ECO will not be available until 2014.

posted 10-11-2013 10:31 AM ET (US)            

The number of blades is pretty much irrelevant. Fewer blades are in theory more efficient. Having more blades can sometimes reduce cavitation by keeping pressure changes better under control. Secondary considerations also control.

The best way to get good midrange economy is to overprop. An engine, which is really an air pump, can develop the same power either with high manifold pressure and low RPM or high RPM and low manifold pressure. Most of the physics favors the former, because of (a) less friction losses; (b) higher cylinder pressures that promote more complete burning; (c) greater time for combustion event; and more.

So, to get the best midrange economy: (a) get the biggest diameter prop you can; (b) select the highest pitch you can live with, i.e. that lets you plane the boat and but keeps RPM as low as possible. You will give up responsiveness and maybe top speed, but you will gain midrange economy.

Until the manufacturers give us multispeed lower units (this should happen, at least a two-speed) its all a compromise.

posted 10-13-2013 10:10 AM ET (US)            

We can see the effect of this advertising on LHG and Tom W. Clark. Both have expressed immediate interest in buying the ENERTIA ECO. It might very well turn out that the propellers they presently own will produce better all-round performance of their boats than this new Mercury ENERTIA ECO can achieve, but by this elaborate promotion of the ENERTIA ECO, Mercury will have sold more propellers than it would have otherwise been able to do.

posted 01-18-2014 12:16 PM ET (US)            

Also, I would very much appreciate seeing a photographic image of a Mercury-brand ENERTIA ECO propeller in direct overhead view and sideways views. In this way, we could see the blade rake and skew more easily, and we could compare with the views seen in

http://continuouswave.com/ubb/Forum4/HTML/006785.html

posted 01-18-2014 01:14 PM ET (US)            

Evinrude REBEL propeller 15-1/2 x 15

posted 01-19-2014 07:33 AM ET (US)            

This video www.youtube.com/watch?v=r67O4h6v2ek from the IBEX show on the Mercury Enertia Eco is interesting. According to the video, the 10 percent improvement claim is with respect to a 32 foot center console using the 4 blade Mercury Revolution 4 propeller. Based on my experience with the Mercury Mirage Plus and Revolution 4 on the same boat, the 3 blade Mercury Mirage Plus was nearly 10 percent more efficient than the 4-blade Revolution 4 at cruise speed. That wasn't unexpected given the Revolution is a 4 blade propeller and the Mirage Plus was a 3 blade propeller. The problem for me was the Mirage Plus would lose grip in choppy water so there was a compromise between improved efficiency and ride comfort. Ride comfort won out and I ran the boat with Revolution 4s.

In my opinion, Mercury set the bar low for its 10 percent improvement claim. Why didn't Mercury compare it to the ordinary Enertia? Seems to me that the ordinary Enertia would be the proper baseline for comparison, not a propeller with 4 blades. The Enertia has been marketed as an offshore propeller and used on offshore boats.

posted 03-08-2014 09:32 PM ET (US)            

quote:

---

...will be available to consumers beginning in February 2014 in right- and left-hand rotation across four pitches: 17, 19, 21 and 23 inches. All feature a 16-inch diameter.

---

http://www.mercurymarine.com/news-and-events/news/2013/9/18/ mercury-introduces-enertia-eco-fuel-saving-propell/

I note that it is now March 2014.

posted 03-10-2014 10:14 AM ET (US)            

It is rumored the left hand 19" as well as 21" and 23" will be available by the end of the month.

posted 04-14-2014 10:09 PM ET (US)            

Ask Ken Reeves, aka "Prop Gods"