Dock Talk on Suzuki DF140

Optimizing the performance of Boston Whaler boats
Blackduck
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Dock Talk on Suzuki DF140

Postby Blackduck » Tue Sep 07, 2021 4:19 pm

Any time the Suzuki DF140 comes up, I feel the need to comment. This is a wonderful engine, however it is not a 140-HP engine. It is no more than a 125-HP. It compares very closely in power output to an old Mercury 115 tower-of-power six-cylinder from the 1970's, a bit stronger, but not much.

jimh
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Re: Suzuki DF 150 on a 190 Outrage

Postby jimh » Wed Sep 08, 2021 10:01 am

Any time someone enters a discussion about actual engine horsepower output of one brand compared to another brand, I feel the need to comment.

The rated power output for outboard engines has since about 1983 conformed to the ICOMIA standard. The applicable ICOMIA standard is reproduced in an article I wrote many years ago, because there was no other source for the standard that was available on-line at no cost. To understand the ICOMIA engine power rating method, just read the standard. See

ICOMIA 28-83
https://continuouswave.com/whaler/refer ... 28-83.html

There is a very commonly repeated misinterpretation of the standard that insists that the rated power can vary by as much as 10-percent from the actual power. That is not true. The standard allows that individual engines in mass production of the product are allowed a manufacturing variance of up to 10-percent above or below the "declared power." The "declared power" must be chosen so that the "highest power" produced is not more than 6-percent greater than the "declared power." There is NOTHING that allows the "declared power" to more than the "highest power" produced. In other words, you can under-rate the engine power on the "declared power" but you cannot over-rate it.

All marine spark ignition engines sold today in the USA must be certified to conform with EPA regulations for exhaust gas emissions, and as a result all outboard engines sold are listed by the EPA with their performance and typically have a metallic label that attests to the compliance. The emission of a particular volume of exhaust gas is measured on the basis of horsepower over tme. Further, engines of different horsepower ranges are allowed different rates of emission. Therefore in certifying an engine for EPA compliance the actual horsepower output of the engine MUST be clearly stated.

You can find the horsepower output of ANY modern outboard engine on the EPA website by downloading their test result database. However it is much easier to just look at the mandatory label on the engine itself that lists the EPA compliance and the actual power output.

For example, on my modern engine the cowling decal declares the power to be 225-HP. The EPA label shows the power as 165.5-kW, which converting that to horsepower gives 222-HP. That is the actual power output produced in the certified test of the engine for EPA compliance in the particular model year (in this case 2010) for the engine. It is common that tested horsepower can vary from model year to model year due to small changes in the engine configuration that affect exhaust gas emissions. I don't lose sleep that the decal indicates 3-HP more than the EPA testing used.

Or you can rely on "dock talk" in which you hear that a one engine brand always makes a lot more horsepower than it says on the cowling decal and that engines from (insert any brand other) will make less power than the cowling decal indicates.

With regard to modern four-stroke-power-cycle engines compared to 50-year-old carburetor two-stroke-power-cycle engines, the modern four-stroke will typically reach its peak power output only at the very highest rated engine speed. For example, if the engine is allowed to run at 6,200-RPM, then the power rating on its decal probably represents the power it can produce at that engine speed, and at slower engine speeds the power output will be less.

To see how power output from modern engines varies with engine speed and engine power-cycle design, you can look at a graph I created based on some data about engine power as a function of engine speed for several engines.

Image
Fig. 1. A plot of engine power output as a function of engine crankshaft rotation speed. Note how the four-stroke-power-cycle engines only reach peak horsepower output at their peak engine speed,

In some instances among engines of similar design and different horsepower ratings, a significant influence on the horsepower rating is the maximum engine speed that is allowed by the engine control module to occur. The higher horsepower version of the various otherwise similar models is usually permitted to run 200 to 400-RPM faster, and that is where the higher power output occurs.

Older two-stroke-power-cycle engine often produced a wider range of engine speeds at which the engine could produce its full power or produce a very substantial percentage of the full power, and the peak power often occurred below the maximum allowed engine speed by several hundred RPM or more, or as shown above as much as 1,500-RPM below maximum allowed engine speed.

Blackduck
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Re: Suzuki DF 150 on a 190 Outrage

Postby Blackduck » Thu Sep 09, 2021 2:23 pm

Here is a professional [Moderator's comment: a manufacturer's promotional flyer] performance test of a boat [similar to the boat now owned] in 1973. My point is that the Suzuki DF140 does have a "dock rap" of being an under performer. I can get to 40 MPH under ideal conditions, 39 is a reliable top end. For me, this is good evidence that the bad rap is justified.

BHBPHOTO331.JPG
Fig. 2. Photo of promotional brochure from Mercury Marine.
BHBPHOTO331.JPG (123.99 KiB) Viewed 2616 times

jimh
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Re: Dock Talk on Suzuki DF140

Postby jimh » Thu Sep 09, 2021 5:58 pm

I do not see anything in the 1970’s test report that could possibly indicate in any reasonable manner anything about the Suzuki DF140 engine that you apparently have some irrational need to trash.

Dock talk is generally recitations of old personal grudges.

If you are unlikely to buy a Suzuki DF140 engine, that is quite fine for you. For you to feel compelled to join ANY discussion that mentions the Suzuki DF140 engine and warn against buying one is a very strange behavior.

My understanding is the Suzuki DF140 is their MOST POPULAR AND THUS BEST SELLING ENGINE. That you want to repeatedly make public avowals that the Suzuki DF140 engine in your opinion barely makes more horsepower than a 115-HP engine from 50-years-ago is particularly a personal judgement on your part and unsubstantiated.

dtmackey
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Re: Dock Talk on Suzuki DF140

Postby dtmackey » Thu Sep 09, 2021 10:52 pm

Blackduck wrote:Any time the Suzuki DF140 comes up, I feel the need to comment. This is a wonderful engine, however it is not a 140-HP engine. It is no more than a 125-HP. It compares very closely in power output to an old Mercury 115 tower-of-power six-cylinder from the 1970's, a bit stronger, but not much.


The Suzuki 140 dyno tested and then certified by the EPA on E10 fuel at 95 kW, and when converted to horsepower (X 1.3402) is 127hp. It has been considered a "weak" 140 for many years.

D-

jimh
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Re: Dock Talk on Suzuki DF140

Postby jimh » Fri Sep 10, 2021 9:29 am

I am not particularly interested in hearing "dock talk" about power output, and how some engine brand and model made 50-years ago produced such-and-such more power than its cowling decal, and because of that there is a proposed logical step to infer that some other brand of outboard must not produce appropriate power.

In regard to offering factual observations about the value in kW that appears on a particular engine's emission certification label and how it varies from the cowling decal rating in horsepower, I welcome reporting of that information, as long as the cited emission label kW number is accurately represented.

Any reasonably well-informed engine buyer can and should be aware of the presence of the emission label power rating (and the weight rating), so there really is no secret being revealed.

FUEL IN TESTING
EPA testing for gasoline engines uses a very specific fuel formulation for the test. All gasoline engines are tested on the same fuel. Since the exhaust emission output could easily vary with the fuel, the concept that only a specific fuel is used in the testing is very reasonable. The EPA gave noticed in 2020 of its plan to change the formulation of the fuel used in testing to an ethanol-gasoline blended fuel ("E10") from pure gasoline.

EPA is proposing technical changes to emissions testing protocols and compliance calculations for the Light-duty Greenhouse Gas (GHG) Emissions Standards and Fuel Economy Standards that would provide a smooth transition from using test fuel with zero percent ethanol (E0) to test fuel that contains ten percent ethanol (E10).

Cf.: https://www.epa.gov/regulations-emissio ... tification

I don't have any particular knowledge that a particular engine was already certified on E10 fuel, but it seems unlikely because the EPA was still proposing this last year, in July 2020. Engine power output on E10 fuel would typically be lower than on pure gasoline fuel.

The EPA does not really test for a particular power output compared to the cowling decal. They test the engines to establish the rate of production of the regulated exhaust gas emissions per horsepower-hour at the horsepower being produced during the test. Compliance with the regulated limits results in the engine earning an EPA rating. It is common for global products like outboard engines to also be certified for use in California and in Europe, whose regulations may require lower rates of exhaust gas emissions.

If a DF140 outboard engine has an emission certification decal that lists the power output as 95 kW, then the power being produced in the certification test was 127.4-HP

Many engines display a cowling decal that contains a horsepower rating that is higher than the power produced in the emission testing. A variance of 10-percent is perhaps larger than expected, but it is not unknown.

The three-cylinder E-TEC 90 engine has a history of varying power output in EPA emission test certifications, with the engine in c.2004 being rated at 67-kW (89.8-HP) and then in c.2016 being rated at 61-kw (81.8-HP). A reasonable inference perhaps is the allowed emission output limits may have changed over the years, and the engine had to be re-tuned to met the increasingly more stringent limits; or, the manufacturer wanted the engine to be certified in another region (California or Europe) whose limits became more stringent, so it re-tuned the engine meet the more stringent regulations.

I think in general that the power rating in kW shown on the emission test label is a good assessment of the engine power output. The notion that the cowling decal power rating and the emission test power measured could possibly differ by about 10-percent should be clear to anyone who understands outboard engine power ratings and emission testing.

I don't know enough about emission testing procedures to comment on whether or not the power output used in the testing is the absolute highest power output possible from the engine under test. I have to assume the testing procedure is also well-regulated, so that manufacturer's cannot easily game-the-system to obtain emission certification.

dtmackey
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Re: Dock Talk on Suzuki DF140

Postby dtmackey » Fri Sep 10, 2021 11:01 am

I was fortunate enough to have lived near Land & Sea performance and spent time there when they were in the business of increasing the power of outboards and Bob Bergeron was the driving force of this business--may he rest in peace as he passed in May of 2019). Bob has some amazing accomplishments, and if you ever visited, you would hear the roar of outboards in the shop being dyno tested. At that time they were located in Hampstead, NH, on Rt-111 and since moved to Concord NH.

Bob was accomplished and brilliant in his business, but saw a better business path in Dynomometers and shifted his business focus to building engine Dynos of his own design that were lower cost and easier to use than competitive units. His product line was called DynoMITE and he catered to the outboard, snowmobile, powersports and grew well beyond those markets. The business grew to one of the more respected in the industry and his son took over and continued to grow the product offerings. They now offer one of the worlds widest range of dyno applications and were recently sold to Power Test, but the NH location is still run by Bob Bergeron's son as the General Manager. The business is now 42 years old and the facility is 50,000 sqft located in Manchester NH.

The one thing I always remember hearing was there is advertised power on the motor, but that doesn't always correlate to real power, and time and time again Land and Sea would prove that when testing outboards. One could argue about fuel, temps, humidity and other factors, but those are corrected with mathematical corrections or offsets.

On many outboards the EPA rated power output (lower or higher) has been conformed with a dynoMITE dynomometer.

The DF140 has been dyno tested by many people and real world dyno testing on the DF140 has shown HP as low as 117hp which helps explain why this motor is commonly described as a weak 140.

Image
Fig. 3. Plot of power versus engine speed for engine with different tuning.

I have read and understand the premise of the ICOMIA standards. We can agree to disagree on this.


D-

jimh
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Re: Dock Talk on Suzuki DF140

Postby jimh » Fri Sep 10, 2021 2:00 pm

I am sure a company that might be offering tuner kits to enhance performance of an engine with stock (and EPA approved) tuning would want to show the greatest possible change in power output that could be achieved by use of their tuning.

I am also sure that among outboard engine dynamometers in use there is going to be some variation in the calibration and accuracy, so that a particular engine that was measured at a certain power on one company's dynamometer in a particular test could have a different power output than a different engine of the same brand and model that was measured on another dynamometer by another agency or testing company, possibly running on different fuel and with different environmental conditions.

It is like the old saying, "A man who owns two watches never knows what time it is."

That was true for a long time, but today, thanks to atomic clocks on GNSS satellites and GNSS receivers that can receive signals from those satellites, it is possible for almost everyone to know the time to an incredible precision and accuracy. However, I do not think the state of the art in engine testing with dynamometers has progressed to similar uniformity in precision and accuracy as atomic clocks and GNSS satellites.

Again, I am most comfortable with citing the actual power in kW that appears on every engine on the emission compliance label. This is all I need to know. I don't need dock talk, or fond remembrances of things past. I am even skeptical of any data provided by the engine maker themselves. To not be aware that all manufacturers would be likely to would promote their engine only using data that showed it to be as attractive as possible would be naive. For that reason, I like data from disinterested third parties--like certified testing laboratories

I even sometimes wonder if the certified testing laboratories might not have a bit of testing bias toward their clients--the ones paying for the testing to be done--to help achieve the desired outcome in the tests. In EPA compliance I am sure the engine manufacturer has to pay for the certified testing of their product. Is there ever a bit of bias in the testing? Probably not very much, if any, as a testing lab would be more worried about retaining their certification than pushing out bad test data to please a client.

Again, citing some real EPA certification test data is just fine. But please, no relentless campaigns about which brand always makes the most horsepower based on digging up 50-year-old tests performed by the manufacturer themselves.

dtmackey
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Re: Dock Talk on Suzuki DF140

Postby dtmackey » Fri Sep 10, 2021 2:32 pm

jimh wrote:I am sure a company that might be offering tuner kits to enhance performance of an engine with stock (and EPA approved) tuning would want to show the greatest possible change in power output that could be achieved by use of their tuning.

I am also sure that among outboard engine dynamometers in use there is going to be some variation in the calibration and accuracy, so that a particular engine that was measured at a certain power on one company's dynamometer in a particular test could have a different power output than a different engine of the same brand and model that was measured on another dynamometer by another agency or testing company, possibly running on different fuel and with different environmental conditions.

It is like the old saying, "A man who owns two watches never knows what time it is."

That was true for a long time, but today, thanks to atomic clocks on GNSS satellites and GNSS receivers that can receive signals from those satellites, it is possible for almost everyone to know the time to an incredible precision and accuracy. However, I do not think the state of the art in engine testing with dynamometers has progressed to similar uniformity in precision and accuracy as atomic clocks and GNSS satellites.

Again, I am most comfortable with citing the actual power in kW that appears on every engine on the emission compliance label. This is all I need to know. I don't need dock talk, or fond remembrances of things past. I am even skeptical of any data provided by the engine maker themselves. To not be aware that all manufacturers would be likely to would promote their engine only using data that showed it to be as attractive as possible would be naive. For that reason, I like data from disinterested third parties--like certified testing laboratories

I even sometimes wonder if the certified testing laboratories might not have a bit of testing bias toward their clients--the ones paying for the testing to be done--to help achieve the desired outcome in the tests. In EPA compliance I am sure the engine manufacturer has to pay for the certified testing of their product. Is there ever a bit of bias in the testing? Probably not very much, if any, as a testing lab would be more worried about retaining their certification than pushing out bad test data to please a client.

Again, citing some real EPA certification test data is just fine. But please, no relentless campaigns about which brand always makes the most horsepower based on digging up 50-year-old tests performed by the manufacturer themselves.

dtmackey
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Re: Dock Talk on Suzuki DF140

Postby dtmackey » Fri Sep 10, 2021 3:03 pm

jimh wrote:Again, I am most comfortable with citing the actual power in kW that appears on every engine on the emission compliance label. This is all I need to know. I don't need dock talk, or fond remembrances of things past. I am even skeptical of any data provided by the engine maker themselves. To not be aware that all manufacturers would be likely to would promote their engine only using data that showed it to be as attractive as possible would be naive. For that reason, I like data from disinterested third parties--like certified testing laboratories

I even sometimes wonder if the certified testing laboratories might not have a bit of testing bias toward their clients--the ones paying for the testing to be done--to help achieve the desired outcome in the tests. In EPA compliance I am sure the engine manufacturer has to pay for the certified testing of their product. Is there ever a bit of bias in the testing? Probably not very much, if any, as a testing lab would be more worried about retaining their certification than pushing out bad test data to please a client.

Again, citing some real EPA certification test data is just fine. But please, no relentless campaigns about which brand always makes the most horsepower based on digging up 50-year-old tests performed by the manufacturer themselves.


No relentless bashing of brands from me, not my style and I feel that the motors today have never been better. I had to chuckle on your time reference, in 1989-1990 I was stationed on Iwo Jima, the master transmitter station for Loran-C chain 9970. We had 3 cesium beam time clocks accrurate down the the nano second, but to maintain the chain we would to an annual adjustment to the femptmosecond (one quadrillianth of a second). The entire chain would make this jump at the same time, so users with their Loran-C receivers wouldn't see a shift in their TDs, which as you know calculated position. The room they were in was completely encased in copper shielding so there was no risk of outside interference.

ICOMIA is not an regualtory body and has no enforcement ability. Their members are organizations/companies within a number of countries and they descibe themselves as a market intelgence organazation that keep standards and statics within the marine industry. My view of the organization is a jack of all trades - master of none, since they perform no testing and instead rely in information provided to them. The thought of that sends shivers down my spine and reminds me of dieselgate where VW and a number of other companies got away with providing incorrect emissions data, while GM and many other companies were trying to figure out how VW and others arrived at their certification.

ICOMIA is a UK head quartered organzation that's into Marina Markets for best practices in storage and operations, Global Covid Restrictions by country, Super Yachts, Import/Export Regulations, Super Yachts Coatings, Market Intelegence, Sustainability. Like any big association, they play nice with the members paying for their existance through membership.

Is ICOMIA neccessary? IMHO, I think they are as it has sence of attempted standardization and monitoring in the industry across the globe, but do I feel they are able to accomplish what some think they can.

I have the EPA files on Excel and ran several filters to weed out Waverunners and other Marine combustion engines, but they are far too large to post in a thread. They are also not easy to understand if you are not familiar with the information contained in the files.

What's also interesting is the EPA rates outboard, or maybe the outboard companies provide this data, of having a useful lifetime of 350hrs/10 years.I can think of a single motor I've every owned that hasn't surpassed that criteria rating.

D-

Masbama
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Re: Dock Talk on Suzuki DF140

Postby Masbama » Fri Sep 10, 2021 6:25 pm

Here is the label on my Suzuki DF140a.
Image
Fig 4. Photo from owner of DF140 showing emission label.

I don’t know what horse power this equals but it is obviously more than 127hp.

This engine is on a 2003 190 Nantucket. It has a t-top which adds weight and drag. With my family of four we can reach a bit over 40 mph. We enjoy tubing and knee boarding of which we have no problem doing with this set up.

I would say this engine for our hull as it is set up is “just enough”. It does the job for us. A 150hp would be nice but it would add more weight and I’m not the type to cruise around over 30mph anyway.

Maybe those dyno tests were performed on the earlier 140hp models before the ‘a’ designation. They may have had a lower dyno test rating.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Fri Sep 10, 2021 7:33 pm

MASABA--many, many thanks for showing an actual emission label from a Suzuki DF140 engine for 2015. The label indicates the power of the engine in kilowatts as 103-kW. To convert that to horsepower gives 138-HP.

DF140EmissionLabel_.jpg
Fig. 5. Close-up view of emission label on 2015 Suzuki DF140a engine showing 103-kW power rating.
DF140EmissionLabel_.jpg (30.4 KiB) Viewed 2428 times


The power shown on the CE emission label for the 2015 DF140 engine posted above is quite different than the recitations that the engine only makes "barely more than 50-year-old 115-HP" or the engine makes "117-HP" on a dynamometer test or that the engine makes only 127-HP as indicated on its emission label.

Showing an image of an actual label is THE BEST method to cite the value of engine POWER indicated on the label. Your photo-image of the label has contradicted all the "dock talk." Thank you.

ASIDE: A CE Mark is a symbol that must be affixed to many products before they can be sold on the European market. The mark indicates that a product: fulfills the requirements of relevant European product directives, and also meets all the requirements of the relevant recognized European harmonized performance and safety standards.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Fri Sep 10, 2021 7:46 pm

ASIDE: I have to mention that a "professional" performance test (which in the context that phrase was used above meant a self test done by the manufacturer of the product that is being tested) conducted in the 1970 would clearly not have been able to measure boat speed using a GPS satellite signal. In 1970 boat speed was probably measured by a Pitot tube speedometer, or perhaps by taking a time measurement (with a stopwatch) for the boat to traverse a known distance on the water. Of course, exactly how you determine with great precision a particular distance on the water is another problem, and likely a source of error in a speed measurement using time-and-distance calculations. Today GPS receivers can measure speed to reasonably good accuracy, at least to 0.5-MPH in the case of a receiver of simple design and to much better accuracy in a receiver that employs carrier phase measurement.

I don't think performance data about boat speeds published in the 1970's can be considered to be extremely precise and accurate. Back then, most boats had no really good method of measuring their boat speed. They might have had a coarsely calibrated dial-pointer gauge with graduations every 5-MPH. In contrast, today most boats have a GNSS receiver and can see a calculated speed-over-ground with reasonable accuracy.

The accuracy of speed calculated from a GNSS receiver will vary with the horizontal dilution of precision (HDOP) that is associated with the particular satellite orbit geometry overhead at the time of the measurement, with the use of precision enhancements such as the FAA Wide Area Augmentation System, and with the general quality of the receiver.

Masbama
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Re: Dock Talk on Suzuki DF140

Postby Masbama » Sat Sep 11, 2021 11:08 pm

Thanks Jim.

ASIDE: A CE Mark is a symbol that must be affixed to many products before they can be sold on the European market. The mark indicates that a product: fulfills the requirements of relevant European product directives, and also meets all the requirements of the relevant recognized European harmonized performance and safety standards.

I never knew this. Quite interesting and good to know.

jimh
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Re: Dock Talk on Suzuki DF140

Postby jimh » Sun Sep 12, 2021 10:53 am

Here is a photo of the emission labels on an Evinrude E-TEC 250 H.O. engine from model year 2008:

Image
Fig. 6. Emission label from c.2009 E-TEC 250 H.O. engine

The rated power in kilowatts is 186.4. That converts to 249.9-HP. The label avows the engine complies with US and California emission requirements.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Sun Sep 12, 2021 12:49 pm

Re precision of timing of LORAN chains: I am sure that there was very good coordination of the time reference in LORAN, but since the location of the LORAN transmitting antennas was fixed and very well known, to resolve the position of the receiver only required that the receiver be able to measure the difference in time arrival to two pairs of two signals and their delays between them.

An often unrecognized breakthrough in technology involved in global satellite navigation that the Air Force had to solve when they were creating their GPS system was to invent atomic clocks that would work in space. Then the clock rate had to be adjusted for the relativity effects of the orbital speed.

In many ways LORAN and GPS use the same principles of radio navigation, but the big difference in LORAN is the transmitters are at fixed locations while in GPS the transmitters are always in very rapid motion.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Sun Sep 12, 2021 1:15 pm

Getting back to the DF140, that engine has a displacement of 2.044-liters. To make its measured 138-HP requires the engine produce 67.5-HP per liter of displacement. Looking at some other engines and their HP-per-liter of displacement:

Honda BF150 2.354-liters = 63.7-HP per liter
Yamaha F200 2.8-liters = 71.4-HP per liter
E-TEC 250, 3.4-liters = 73.5-HP per liter

The Suzuki's 67.5-HP per liter is right in the middle of that range. Yet I have never heard any dock talk that the Honda BF150, the Yamaha F200, or the E-TEC 250 engines are "weak" engines. Further, I have never experienced a situation where an individual felt compelled to enter into any discussion of those other engines to warn against buying them due to their power output being "weak."

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Re: Dock Talk on Suzuki DF140

Postby Blackduck » Mon Sep 13, 2021 10:07 am

Call it bashing, call me what ever you want, the df140 is still a pig.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Mon Sep 13, 2021 5:21 pm

Blackduck wrote:Call it bashing...the df140 is still a pig.

I already explained, "dock talk" is generally recitations of old personal grudges.
Blackduck wrote:...call me what ever [sic] you want...

I have called you nothing at all in this thread. I just found your comparison to an ancient boat performance test by a manufacturer to have no relevance to the DF140a power output. I found your self-confessed compulsion to enter any thread that mentions the DF140 and advise against purchase of it to be unusual behavior. You seem to be on a crusade to defame the DF140a, and you won’t let go even in the face of good evidence that it produces 138-HP.

dtmackey
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Re: Dock Talk on Suzuki DF140

Postby dtmackey » Thu Sep 16, 2021 2:52 pm

The CE marking is a little misleading as it does not specify to what they "certifying" to the CE marking. I believe you (Jim) are referring the CE marking which is made for the assessment meathods for exhaust emissions measurement (EN ISO 8178-1:1996) B+C, B+D, B+E, B+F, G or H. This is under compliance meathods Directive 97/68/EC (non-road mobile machinery), Annex I, section 4.2.3 (stage II).

Companies self certify for this, send in paperwork and receive permission to apply the CE marking to a decal and affix to an outboard motor. Over the years there's been a movement within CE on the following items:

- Enhanced market-surveillance provisions - I welcome this as this would tighten the testing and keep manufactures honest.
- Simplification of administrative procedures - probably so complex, things slip through the cracks.
- Monitoring of emissions from in-service engines - Another welcomed idea.
- Type-approval also for gas-fuelled engines (partial/mono)
- Eliminating "greyzones" (field testing) - Field testing would tighten up the loosey goosey horsepower ratings.

While the CE model isn't perfect, it's headed in the right direction, however it's a struggle when so many different countries are involved with the direction of CE.

The data from the EPA website is certified to emissions as well, but also carries a power rating in kW (as tested) and that shows a different indication than the CE sticker. The 2014 Suzuki 140 is certified to the EPA at:

Data taken direct from the EPA website, HP conversion is made using the equation 1kW = 1.34102 horsepower
Image

No company is going to get "punished" by an authorative body over a horsepower rating that doesn't match a decal applied to a motor, but if the emissions are no inline there are massive penalties that will be applied.

I am not in agreement your methodology of hanging your hat on a small 2" decal a manfacturer applies to a motor as there's far more complexity behind that decal than just reciting a number.

Let's agree to disagree on this as there's no supporting information supporting your position.

D-

jimh
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Re: Dock Talk on Suzuki DF140

Postby jimh » Fri Sep 17, 2021 7:17 am

That data from EPA shown above does not indicate that it applies to the DF140. The designator for "Engine Family" should appear on the EPA label. Compare with the label shown above on an Evinrude in Figure 6.

I believe someone once pointed out that all the Evinrude E-TEC engines using the 3.4-liter engine block were rated under the same "Engine Family" for EPA, and all were certified at the same horsepower output, about 250-HP. Some of those engine carried model designators and decals for "300" and some carried " 250 H.O."

Notice that the EPA compliance label generally does not have a power rating. Only the CE label has the power rating.

There has long been an understanding that these high-rotation-speed rated engines with four-stroke-power-cycle design only hit their peak power at the absolute peak of their allowed engine speed. And the power output curve is similarly shaped. Engines with a higher power output at lower engine speeds, often two-stroke-power-cycle engines, will be able to more easily accelerate under the load of a propeller at those lower engine speeds. See my article on Propeller Power Curve for some graphs that demonstrate how engines with strong power output at lower engine speeds will be able to accelerate better under load.

Propeller Power Curve
https://continuouswave.com/whaler/refer ... Curve.html

In order to obtain the rated maximum power output from any marine engine, the propeller must be chosen so that the propeller load permits the engine to accelerate into its maximum power output range. In the case of many (perhaps most or even all) four-stroke-power-cycle outboard engines, that means the propeller load must be chosen to permit the engine to accelerate to its very highest rated engine speed.

If any engine is not mated properly to a propeller, that is, the propeller load is too high, the engine speed will be limited, and the engine will only be able to accelerate to some engine speed below its maximum power output. The result will be less power output from the engine at full-throttle than the engine is rated to produce.

dtmackey
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Re: Dock Talk on Suzuki DF140

Postby dtmackey » Fri Sep 17, 2021 9:42 am

jimh wrote:That data from EPA shown above does not indicate that it applies to the DF140. The designator for "Engine Family" should appear on the EPA label. Compare with the label shown above on an Evinrude in Figure 6.


So if I understand you correctly "Engine Family" is for all the motors within a common family - same engine block size, design and other characteristics?

If that is the premise, then the engine family would apply to the Suzuki 115 and 140hp model as they use the same 124.7 cu in block and if that's the case then the EPA rating of 127hp is applied to the 115 model instead of the 140hp model I am suggesting. Is this what's being implied?

I highly doubt any engine manfacturer would underrate their motors by 12 horsepower and slap a 115 decal on a motor capable of 127.5hp. Is it possible that they are using the average of the advertized horsepower rating? This would seem to make more sense as the average of the 115/140 family is 127.5hp and that's the rated power in the EPA family, BUT then applying this to the 2020 Evinrudes wouldn't add up when looking at the 3.4L displacement models since there's multiple ratings for the same displacement and these separate horsepower ratings are broken into different families. For the sake of Evinrude we both know the 3.4L block was used in models 200HO, 225HO, 250, 250HO and 300.

More questions than answers on what is the real horsepower of the Zuke 140.

I'm sure that when a manufacture goes to certify an engine that the stars and the moon are aligned so that the motor is in peak operating condition and these perameters would never be achieved in the real world. After all there are so many factors that come into play once a motor is bolted on a transom and has a little use behind it.

D-

Blackduck
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Re: Dock Talk on Suzuki DF140

Postby Blackduck » Fri Sep 17, 2021 11:37 am

jimh wrote:In order to obtain the rated maximum power output from any marine engine, the propeller must be chosen so that the propeller load permits the engine to accelerate into its maximum power output range. In the case of many (perhaps most or even all) four-stroke-power-cycle outboard engines, that means the propeller load must be chosen to permit the engine to accelerate to its very highest rated engine speed.

If any engine is not mated properly to a propeller, that is, the propeller load is too high, the engine speed will be limited, and the engine will only be able to accelerate to some engine speed below its maximum power output. The result will be less power output from the engine at full-throttle than the engine is rated to produce."



When an engine rated for 6200 RPM can turn no more than a 17" pitch prop to reach that rotation speed, there is no way of obtaining more performance, from that unit. Propeller design can improve or hinder, but in essence, it is that simple. Boat weight and cargo come in to play, but I know my boat's weight and bottom condition. The only way to make a boat go faster is to increase prop pitch, and in this case the motor will not do that, therefore, maximum performance from that engine has been achieved.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Fri Sep 17, 2021 10:20 pm

Blackduck wrote:When an engine rated for 6200 RPM can turn no more than a 17" pitch prop to reach that rotation speed, there is no way of obtaining more performance, from that unit.


The engine rev-limited might be kicking in at 6,200-RPM, so you have to be careful that the propeller load is really what is limiting the engine speed, not the rev-limiter.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Sat Sep 18, 2021 8:49 am

I can’t offer a definition for the EPA term “engine family.” I just infer it means engines of similar emission characteristics, which I then also infer means engines of similar power output so thus covered by the same regulations, and engines with similar rates of output per horsepower-hour of the regulated emission components.

To make power the engine consumes fuel. The more power produced, the more fuel consumed. The more fuel consumed, the more exhaust emitted.

Engines of very similar design should have—really must have—the same thermal efficiency in converting fuel to power. An engine that is producing 140-HP must consume more fuel than a nearly identical engine producing 115-HP. The only way an engine becomes more fuel efficient is through significant change in its design. No engine maker would create similar engines with different horsepower-rating by intentionally making the the lower-horsepower versions less efficient than their higher-horsepower model of nearly identical design. To make more power output (with no significant change in design) the higher-power-rated engine must burn more fuel.

On another aspect, if the DF140a only made a tiny bit more horsepower than the 115-HP model, I would expect that on-water performance test reports would reveal this.

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Re: Dock Talk on Suzuki DF140

Postby Masbama » Sat Sep 18, 2021 1:12 pm

jimh wrote:
Blackduck wrote:When an engine rated for 6200 RPM can turn no more than a 17" pitch prop to reach that rotation speed, there is no way of obtaining more performance, from that unit.


The engine rev-limited might be kicking in at 6,200-RPM, so you have to be careful that the propeller load is really what is limiting the engine speed, not the rev-limiter.


On [my 2003 190 Nantucket boat, the Suzuki DF140a engine] turns a Suzuki three-blade, 20-pitch propeller, and with a light load [the engine can accelerate until it] hits the rev limiter.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Sun Sep 19, 2021 10:22 am

With multi-cylinder engines, one cylinder could be lost, that is, not having any combustion, and the operator might not be aware of the problem. The engine seems to run normally, but its power output is reduced.

For example, I was running a V6 engine that would often be running on only five cylinders. I never noticed this problem. It was only upon installation of a gauge that could measure fuel economy (MPG), that I began to observe an occasional change in computed MPG would occur, accompanied by a slight change in engine speed (RPM). I began to investigate the cause of this, and found that one cylinder was loosing spark. After working on the diagnosis of the cause by replacing the spark plug, the spark coil, and the spark wires for that cylinder, I eventually determined that the engine's spark generating module (Power Pack) was the likely cause of this intermittent problem. I replaced the module and the problem was solved.

I would have never really noticed the problem if not for the addition of the fuel economy gauge. It was a noticeable drop in fuel economy that accompanied the loss of one cylinder in combustion that really alerted me to the malfunction in the engine. Other than that, I would probably have not noticed anything was wrong, and just continued to run the engine with only five cylinders working all the time.

Of course, with the sixth cylinder restored to operation, the engine power output improved, as did the boat's speed and acceleration.

I mention to illustrate that the power output of an engine can be affected by many variables, and the notion that because one person reports his particular engine seemed to produce insufficient power, one should not automatically assume that engine to be representative of all engines of that model.

Blackduck
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Re: Dock Talk on Suzuki DF140

Postby Blackduck » Tue Sep 21, 2021 12:54 pm

For the record, the engine I own has 65 hours of service, and functions as one would think a brand new engine would.

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Re: Dock Talk on Suzuki DF140

Postby jimh » Tue Sep 21, 2021 1:18 pm

Blackduck wrote:For the record, the engine I own has 65 hours of service, and functions as one would think a brand new motor would.

For the record, please indicate what engine you own.

I reviewed your comments herein and don’t see any clear identification of your engine.