PowerTech! Propellers
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PowerTech! Propellers Receives 2011 IBEX Innovation Award

LOUISVILLE, Ky., October 17, 2011 
The National Marine Manufacturers Association (NMMA), along with a judging panel from Boating Writers International (BWI), today selected the POWERSTOP! Propeller by PowerTech! Propellers as recipient of a 2011 IBEX Innovation Award for Propulsion Parts / Propellers. 

BWI and the NMMA presented the 2011 award at the International Boat Builder's Exhibition (IBEX) show and conference at the Kentucky Exposition Center in Louisville, Kentucky.  

The IBEX Innovation Award is the industry’s highest honor for innovative and technological advancement. The award recognizes advancements in OEM and aftermarket equipment based on specific criteria: innovative distinction from other products currently being manufactured; benefit to the marine industry and/or consumer; practicality; and cost effectiveness.  

The latest PowerTech! Propeller design, named the PowerStop!, incorporates the world’s first reverse thrust propeller that performs great in both forward and reverse directions. This new design incorporates unique cupping, on both the leading and trailing edges, thereby enhancing control for stopping, reversing and maneuvering. Having the ability to stop quicker and maneuver accurately in reverse make this design inherently safer for family and novice boating activities. 

While traditional propellers are designed with forward motion in mind, and previously reverse direction props were designed with rearward motion as the priority, the PowerStop! is designed to work well in BOTH directions. “The rapidly growing pontoon and deck boat market is always faced with ways to reduce the effects of wind, tide and a variety of performance issues. PowerTech Propellers answers those concerns with a brilliantly crafted reverse thrust propeller, providing new levels of control without harming overall performance,” said Judge Brady Kay. 

PowerTech! Propellers has now won back-to-back IBEX Innovation Awards for 2010 and 2011. With over 25 years of innovation PowerTech! leads the world in propeller designs/part numbers, manufacturing more combinations of features than any other propeller manufacturer. 

“We are proud to have earned this award of distinction from both the NMMA and the BWI, which verifies our commitment to new product development and cutting edge designs,” said Steve Powers, founder and president. With nearly half a million propellers in service on every continent, PowerTech! Propellers has established itself as one of the top-tier propeller companies in the world.  


Editor’s Note: Information for media regarding PowerTech! products is available at 800-736-7767or 318-688-1970. Consumer information regarding PowerTech! products is available at This email address is being protected from spam bots, you need Javascript enabled to view it . For product inquiries and dealer locations, please visit www.ptprop.com.
PowerStop! Reverse Thrust Propeller Offers Safety and Control

PowerStop! Reverse Thrust Propeller Offers Safety and Control

PowerTech!’s new PowerStop! reverse thrust propeller provides new levels of control without diminishing the boat’s overall performance.  This new design (patent pending) incorporates unique cupping on, both, leading and trailing edges to improve stopping, backing, and maneuvering performances. 

While traditionally cupped propellers are designed with only forward motion in mind, and previous, reverse-cupped propellers have been designed with only rearward motion in mind, PowerTech!’s new PowerStop! is designed to work in BOTH directions.  With cupping faired into the underside of the leading edge and an aft-tapered cup incorporated at the top of the trailing edge, the PowerStop! retains grip and control, whether moving forward, or backward.  In testing, stopping distances and reverse thrust improvements of up to 300% were indicated. What this means to the boater is better control and greater safety, whether in open water, or maneuvering in the tight confines of a marina, or crowded dock. 

The PowerStop! is presently available in aluminum propellers for E-class motors, from 150-300 hp, and in 15.5” x 11”, 15.5” x 12”, and 15.5” x 13”. 

PowerTech!'s PowerTorque! Wins IBEX Innovation Award
PowerTech!'s PowerTorque! Wins IBEX Innovation Award

Louisville, KY
– PowerTech! Propellers’ new PowerTorque! hub system was recognized by the National Marine Manufacturers Association (NMMA) and Boating Writers International (BWI) for this innovative achievement in the Propulsion Parts, Propeller division.

PowerTech! Propellers president and CEO, Steve Powers accepted the award at the 18th annual International BoatBuilders Exposition and Conference (IBEX) at Kentucky Exposition Center. The IBEX annual show has become one of the premier venues to showcase the marine industry’s newest product offerings.

“We are truly honored that the judges recognized the PowerTorque!’s merits,” said Powers.  “To win this award at a show of this magnitude, and against such distinguished competition, gives us a great sense of satisfaction.”

The PowerTorque! hub system is a driveline protection system designed to protect gearboxes, propellers, and other parts of the driveline from impacts.  It is unique, in that, it is the only reusable outboard/stern drive hub system and inboard driveline protection system on the market that automatically releases and, then, resets to full torque capability.

Upon impact, the PowerTorque! system disengages and acts as a compact clutch that absorbs the shock load, thereby, protecting the driveline AND the propeller.  Unlike the sacrificial plastic hubs that strip their splines to save the driveline and props from damage, stranding the vessel, the PowerTorque! automatically re-engages, once the obstruction/resistance is cleared.  From that point, the vessel is able to continue without further loss of drive.

According to Powers, “It sounds cliché, but the PowerTorque! hub system is quite literally the last hub system you will ever need to buy.”

At present, PowerTorque! hub systems are compatible with the universal square-hub-driver systems used by all major propeller manufacturers, and the Driveline Protection System is available for shafts ranging from 1” to 2 ½”.

“Anyone who has replaced a lot of hubs will love this one, and it will get you home,” said Chris Caswell, innovations judge, author, and senior editor, Yachting Magazine.”

The IBEX Innovation Awards program is one of the marine industry’s most prestigious honors.  Created by the National Marine Manufacturers Association in 1992 and judged by members of Boating Writers International, the Innovation Awards find the marine industry’s best and most innovative products, products that stand out from others currently on the market.
PowerTech! Introduces Props for New PowerTorque! Hub System

PowerTech! Introduces Propellers for New PowerTorque! Hub System

Spun hubs?  Twisted drive shafts?  Lower unit damage?

PowerTech! has released a new line of E-Class propellers which are specifically designed to house a revolutionary new hub system called Safety Torque. Unlike any other hub system in the world, PowerTorque! provides repeated protection with no down time and zero maintenance.

 Propeller hubs are designed to absorb the energy that is produced in an underwater impact.   Typically a normal plastic or rubber hub do what they are designed for, but once the hub encounters a shock load it “spins out”, and leaves the vessel immobile.  This leaves the boater with only two options, provided there is a spare hub, prop, and tools onboard.   The boater can face the elements and get into the water to make a difficult repair onsite, or send a coast guard S.O.S (provided they have a radio) and have the vessel towed back to port.  This is of course the best case damage scenario.   If the prop strikes an object with enough force the damage goes beyond the hub and can result in very costly lower unit repairs.

So what sets PowerTorque! apart from the rest?  PowerTorque! hubs are factory preset for a specific torque load.  As the prop strikes an object, the hub releases to absorb the shock load, protecting the propeller, drive shaft, gears, and gear case from twisting and breaking loose.   Once the obstruction has cleared the hub automatically resets and the vessel is able to continue at full power.  The PowerTorque! Hub System is offered in PowerTech’s E-Class series of stainless steel propellers.

PowerTorque! also offers a Driveline Protection System which functions like the Hub System.  This system replaces the propeller shaft coupler attached to the transmission output flange.  The Driveline System is offered on the following transmissions listed below, as well as other custom applications.

               PowerTorque! Specifications
                 for In-board Marine Applications
PowerTorque!Models FitsTransmissions Shaft Sizes(max.) Torque(ft. lbs)
Model A KM35P 1” 45-325
  KM3V 1” 45-50
  KM35A/35A-2 1” 45-325
  KM2P-1 1” 70-285
Model B ZF30M 1 ½” 350-575
  ZF25A 1 ½” 300-500
Model C KM4A1 1 ¾” 440-500
  KM4A-2 1 ¾” 250-560
  KMH4A 1 ¾” 320-375
Model D ZF45 2” 380-1300
  KMH40A 2” 380-1300
Model E ZF63A1 2” 600-1230
  KMH50 2” 620-890
  KMH50A 2” 700-1250
  ZF63A 2” 630-1280
Model F MG5061A 2 ½” 860-1330
  KMH61A 2 ½” 1180-2200
  ZF85A 2 ½” 1195-2270


PowerTorque!, buy it once use it for life.



Prop Damage, Repair or Replace?
Prop Damage, Repair or Replace?  

So, you looked at your prop and it isn’t looking so great.   Should you repair or just replace it.  Here are a few tips to help you decide. 

First of all, was your prop doing a good job before it was damaged?  It is critical that your prop can keep your motor in the proper rpm range.  Failure to do this results in poor fuel economy, poor performance, and most expensive of all—potentially catastrophic damage to your motor.  Second, did your boat accelerate and corner well?  If there are issues with these items, it might be time to consult with a prop manufacturer or your propeller dealer and replace your prop.  After all, a prop that is perfectly repaired, but is not properly suited for your application—is perfectly improper.

(Note:  If you are experiencing noticeable vibration from the prop, you should immediately repair or replace the prop.  Nothing good comes from vibration!)

However, if the basic performance factors were OK, we will need to evaluate the feasibility of repairing the prop.

If you have an aluminum prop, you should inspect for excessive metal loss, extended cracks, too thin blades, or cavitation burns.  If you have more than 10% of your blade area missing, or other problems, it may be better to replace the prop.  An additional consideration is whether your prop may need the inner hub that protects your drivetrain replaced.  This can add another $40-60 to the repair cost, so it needs to be examined as well.  Aluminum propellers are fairly inexpensive to purchase new, so you don’t want to put too much money into them, unless they are in pretty good overall condition.

What if you have a V drive or inboard ski boat/cruiser with bronze wheels?  The critical issue here is blade thickness.  Even if you made a “pretzel” out of your prop, skilled prop shops can work wonders.  But, if the blades are excessively thin, you may be sinking money into a lost cause.  When you straighten, you need to regrind to smooth the surface and remove dents/nicks.  Each time this is done, critical metal thickness is lost.  Remember that a 20% reduction in thickness may reduce the strength by up to 50%.  These wheels are more expensive than aluminum, so if the thickness is OK, repair is a very cost-effective decision.

Stainless props need to be evaluated on similar criteria.  First of all, is the remaining thickness OK?  Any signs of cracks?  How extensive is the damage?  How much metal is missing?  Generally speaking, stainless props are made from two general types of metals.
High carbon stainless is very strong and damage resistant.  It welds well and can generally be repaired unless it is bent excessively.  Given its high strength, it does not like being bent into a pretzel and straightened.  Typically this metal is used by Mercury, Yamaha, Turbo-Stiletto (now a Yamaha company), Michigan Wheel, and PowerTech.  Another characteristic of high strength stainless is the fact that is shows more corrosion than low strength stainless.  This is a natural consequence of the higher carbon steel content used in the alloy. 

Low strength stainless uses more nickel in the alloying combination.  This provides a significant increase in corrosion resistance, but also drops the tensile strength, typically by 50% compared to the high strength material.  The material is more similar to that used for deck hardware.  Since the strength of the material is more like bronze than a high strength stainless, it will “pretzel” pretty easily.  The good news is that it can normally be straightened out again.

In either case, the issue will be to examine for enough blade thickness to allow the repair to be completed and still have sufficient “meat” left for durability.

If the decision is to repair the prop, look for a well-recommended repair shop.  The proper repair of propellers is an art.  It takes a true skilled technician to do the job you want.  There are many good repair facilities available.  If you have a prop shop that is doing a great job for you, stay with them.  However, if you are looking for a shop, let me recommend the NMPA.  We are members of the National Marine Propeller Association (http://www.nmpa.net), which provides training and workshops to help its members keep their technical skills current.  It may be a good resource to assist you in finding a skilled prop shop.  We also have a dealer list on our website www.ptprop.com.

In any case, let’s get your prop taken care of, so you can get out on the water and have some fun!

Steve Powers
PowerTech Propellers
…To Four, or Not To Four…That is the Question

...To Four, or Not To Four...That is the Question

For many years, now, boaters have debated the question of 4-blade propellers versus 3-blades.  The traditional argument is that 4-blades are slow and 3-blades are fast, end of discussion.  Today, new trends in the marine marketplace, higher fuel prices, challenging economic times, and the like have all brought new concerns to the boating world.  Speed is, now, a much smaller part of the equation; while practical, real world performance becomes the consumers primary concern.  In this new modern age, the question arises anew, but this time, with a different answer. 




In the beginning, the idea that 4-blades were slower than 3-blades was true to a certain extent, but that is because many of those 4-blades were not designed with speed in mind.  Instead, the few designs that were available were intended to cure handling issues such as ventilation, cornering blowout, motor elevation requirements, and holeshot issues.    Without many options in blade design, and very few of them truly intended to be particularly fast, the 4-blade got branded as slow, while their other performance benefits were largely dismissed.  By contrast, today’s 4-blade propeller designs have evolved into, both, all-purpose and highly specialized geometries.  These propellers can be tailored to, not only, address those traditional handling issues, but can also be tailored to improve a boat’s performance envelope, which can, in some cases, even include speed.


The increased blade area afforded by the addition of the fourth blade can provide increased water displacement capability, lift, and grip, as compared to the comparable     3-blade propeller.  In terms of actual boat performance, these characteristics can combine to enhance handling, holeshot, low-speed planning ability, cruise efficiency, fuel efficiency, load-carrying performance, big seas performance, following seas/down current performance, ventilation/cavitation resistance, motor elevation capability, etc.  In short, a 4-blade propeller can improve all those characteristics that make for practical, all-around boat performance.


So, why might a 4-blade generally be slower than its 3-blade counterpart?  To be honest, many 3-blade/4-blade speed comparisons are simply not fair. That’s because the respective propellers in question are simply different styles, designed with different purposes in mind—different diameters, rakes, cupping, and blade shapes.  If, however, for comparison purposes, we take two propellers, identical in design (blade shape, diameter, rake, cup, etc.) that is appropriate for a given application, and simply add a propeller blade, we get a truer representation of just where the difference lies.  The addition of the extra blade causes increased drag, which, in turn, requires more horsepower, in order to achieve the same rpm. Since the horsepower is limited, the rpms drop, and the speed will tend to drop with it.  This is why, when going from a 3-blade to a 4-blade, the pitch is dropped an inch, or more, in order to keep rpm parity.  It is this difference in pitch that causes any potential speed differential between the 3-blade and the 4.


As to any actual speed loss between the two, in many cases, it is actually quite small (generally 1-3 mph).  The reason is, although the 4-blade is one-inch lower in pitch, it runs more efficiently than its 3-blade competitor, allowing it to run closer to its theoretical speed than the 3-blade, thereby, effectively closing the gap presented by the pitch differential. 




As the result of many of today’s trends in the marine marketplace, 4-blade propellers have become more popular than ever.  As fuel prices have risen, fuel efficiency and cruise efficiency have become prime concerns for boaters, and 4-blades can offer improvements to both.  Other trends in the marine industry, such as, the move toward 4-stroke motors with their heavier weights and higher numerical gear ratios, shallow-flats boats, tunnel boats and cat boats with their ventilation-prone running characteristics, ski-boats with their pulling requirements, heavier deep-V offshores with their big seas control requirements, can all benefit from the additional grip, lift, and efficiency of 4-blade propellers.  In short, 4-blade propellers have become almost indispensable in maximizing boat performance and customer satisfaction. 


Where customers were once resistant to the idea of a 4-blade propeller, we are actually finding that customers come to us asking if their applications will benefit from the use of a 4-blade propeller.  In many of these cases, the answer is a resounding, “yes.” 




As we have learned more about what makes a propeller work and not work, and about how boats and motors perform and do not perform, we have designed propellers that address the inherent strengths AND weaknesses of each of these respective pieces of the puzzle.  These designs have become even more important as more and more specialized boat designs and motor trends have entered the marketplace and as new trends and economic challenges arise.  All that said, the most important part of the equation remains the customer’s performance expectation and satisfaction; so, the goal is to match the propeller to the boat, motor, AND the customer’s needs…as always, the right tool for the right job.


Marcus Clements
a.k.a., Funky Monkey from Maverick Boat Company's customer message forum at www.mbcboats.com

Times, They Are A-Changin’

Speed has always been the foul temptress of the marine industry.  Everyone wants to go faster than they “bought,” and fuel has always been relatively cheap.  Global Positioning Sensors (GPS) made this all the more critical, as speed could, then, be measured to the tenth of a mile per hour.  At the same time, fuel mileage was rarely, if ever, a concern.  If speed is the foul temptress, then fuel efficiency has been the proverbial, red-headed stepchild…that is, until now. 


Soaring fuel prices have changed the very nature of much of the marine industry’s focus because their customer’s performance expectations have changed.  Customers who, once, wanted every scintilla of speed they could muster, are now looking to maximize their boat’s fuel efficiency and range, instead.  Just as with any aspect of boat performance, the propeller holds the key. 


The only reason a propeller-driven boat moves, at all, is because the propeller displaces (moves) water beneath the boat.  As luck (and physics) would have it, the hull of the boat and the water, together, are pretty slippery, so as the propeller displaces this water beneath the boat, the boat moves across the top of the water.  The more efficiently the propeller moves this water, the more efficiently the boat moves, which makes the motor’s job easier.  If the motor is working with less strain, it will use fuel more efficiently.


Granted, this is an oversimplification, but it does address the basics of what can be a very complicated scenario.  There are many other factors to consider, such as, does the boat require sternlift to offset a rearward bias in the center of gravity, or bowlift to reduce wetted surface area (friction), or is the inefficiency due to propeller slip (whether hull, motor elevation, or propeller geometry related).  Whether it is weight-, friction-, balance-, or grip-related, all of these issues can often times be addressed, to one degree, or another, just by changing a propeller. 


Whether an application’s fuel efficiency and range can be improved upon with a propeller really depends on just how well it is propped, initially.  In some instances, the boat is propped correctly and there is very little to be gained, while in others, the propeller is incorrect for the application and significant improvements can be found.  The degree to which this can be done will be highly dependent upon just what the boat/motor combination is lacking, and just HOW lacking it is. 


In one particular example, we were asked by an OEM boat manufacturer to address just such an inefficiency on a 32-foot performance cruiser with twin 250 hp 4-strokes.  The boat had an excessively high minimum plane speed (marginal plane below 4100 rpm), poor low-speed handling characteristics, excessively high fuel consumption, and excessive bowlift running the stock moderate-to-high rake 15 ½” x 17” 3-blades. 


In this case, it was determined that the boat was suffering from a rearward-biased center of gravity, and propellers without sufficient blade surface area.  In order to address this, we increased blade area by increasing the number of blades to four, utilized a propeller geometry with lower rake for more sternlift, and dropped the pitch one inch, to ensure that we allowed the motors to run in the heart of their torque band.  As a result, at the target rpm of 3500, the original 17” 3-blades ran 15 mph lightly loaded and 11 mph loaded, using 14.5 GPH.  At the same rpm, the 16” 4-blades ran 23 mph and 22 mph at the same respective loads, and used only 13.5 GPH.  As you might expect, the fuel range was similarly extended.  As icing on the cake, the tester’s comments on the boat’s improvement in “feel” were just as important to the manufacturer as the performance gains.  It’s a bit like redesigning the boat, without ever going back to the mold.  Now, this is an unusual case, and not one that will be repeated often, but it does give a very good example of what can, and sometimes does, happen just by changing propellers.


Whether you are interested in fuel mileage, speed, holeshot, handling, load-carrying, or what have you, it is critical to choose the right tool for the right job.  Just as the right prop can make a boat, the wrong prop can break it, so once you determine the aspects of performance that are most important to you, take the time to find the prop that best satisfies YOUR needs.




Marcus Clements
a.k.a., Funky Monkey from Maverick Boat Company's customer message forum at www.mbcboats.com

The PowerTech! Family
Well, it has been another very successful year at PowerTech!, and we have you to thank for it, yet, again. We say, “again,” because at our present rate of growth, we should end 2007 with double-digit sales growth over what was already a record year in 2006. Not only did we see amazing growth in the aluminum market, which we joined in August of 2006, but in the stainless steel market, as well.

In a continuing effort to expand into new markets and improve our product selection, we have been quite busy building new tools (molds), so that we can, not only, build new propeller designs, but also add to our available pitch ranges for existing designs. This may seem at odds with the simplification that many manufacturers seek, but for us, we see a continuing need to offer an even wider array of products to meet the many, and varied, demands of the marine industry. For example, with the advent, and sales success, of 4-stroke power plants, “big foot” motors, and the like, this has become even more critical, since the weight, power delivery and, even, gear ratios often change from their more traditional cousins. These types of changes can, often times, require changes in propeller geometry, pitch or, even, blade surface area. As always, the right tool for the right job.

We thank you, yet, again, this year, as this would not be possible without you, our PowerTech! family members.

Aluminum Line Expands
Our aluminum line of propellers has been quite successful this year. We began our line with, what we felt was, a comprehensive list of part numbers, but we anticipated expanding that range. Now that we have had some time in the market, we have a better understanding of what products we need to add, in order to fill in any gaps that exist in our line. To that end, we are adding eight new propeller part numbers to our aluminum line and will continue to listen to you, our customers, so that we are aware of those propellers we may need to add in the near future. As we see a significant demand, we make arrangements to add those part numbers, accordingly.

Along with expanding our aluminum propeller range, we will be increasing aluminum inventories for the 2008 season, as well. Just as this year taught us of the propeller part numbers we needed to add to the line, we also learned that we needed to increase our inventories in order to keep pace with demand. Our goal is to have the part numbers you need, when you need them.
PowerTech! TRO4R28
This is a small-tube four-blade prop that allows exhaust gasses to flow both through and across the tube and into the blades. This can cause ventilation problems either on initial acceleration or as the boat breaks onto a plane. There were no problems with the PowerTech. The visual appearance of this prop is very close to the Mercury Trophy, but notice the difference in acceleration times and top speed.

The PowerTech! TRO4 demonstrated another important factor that shows just how critical setup and engine height can be to good handling and maximum performance. We started our testing with the propshaft setting at 3- 1/4 inches below the bottom of the hull. At this point, chine walking and steering torque was a handful. Each 1/4 inch up reduced both steering torque and the tendency to chine walk and when we were up a full three-quarters of an inch (propshaft 2-1/2 inches below the bottom of the boat), steering torque was greatly reduced and the tendency to chine walk had just about disappeared.

This is an excellent prop.

"The above is a reprint of an article comparing performance and price of the PowerTech! TRO4 blade style with props by other leading manufacturers. reprinted with permission from Bass & Walleye Boats Magazine"
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