This article explores the different types of ski propellers, their benefits, and how to select the best prop pitch, material, and size for your water ski boat. The Mercury Propeller Selector tool on MercuryMarine.com helps boaters select the best propeller model and pitch for their boat, ensuring smooth operation and dependability.
Choosing the right propeller for your boat depends on whether you’re pulling water-skiers, wakeboarders, or towing tubes. Four-bladed propellers offer more torque at the low end and mid range, making them ideal for waterskiing and tubing. They also get the boat to plane quicker, pushing more water, making the boat get up and go.
For pulling skiers, the Cyclone prop is recommended, starting with a 17-inch engine on V6 and Glastron. For hard-core skiing, the Enertia is one of the faster props, but it doesn’t like to run in the 20-25 MPH range. For top-end speeds, stick to the three-blade.
A 15-pitch prop can improve performance, while a 13-pitch prop may be dissatisfied with speeds. Stainless steel props are stronger than aluminum and have better performance. The High 5 is considered the best holeshot prop, working well on IOs because they like to run deep in the water.
Machined nibral props from OJ and Acme offer the best of both worlds for ski boats, with the 3 blades being the best option. A Laser II 19P three blade propeller is recommended for its quick planes, pulls a skier and tube well, and tops out at 50-53 with only one person in the boat, fuel, and fishing gear.
📹 The Correct Prop For Your Boat! How To Know!
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📹 How to choose right prop for your boat and motor
How do you know if your using the right prop for your boat?
I just went from a 3 blade 21P prop to a 4 blade 19P prop on a 17′ family boat (Glasspar, Merc 90CT outboard) and there were three notable differences. You could trim further up with the 4 blade before ventilation, so a bit more top end RPM with less set towards one chine. You have better throttle control at cruising speed. Our preferred is 3,600 RPM and the 4 blade allows finer throttle control around that range. And we come up right now. The 3 blade was Ok, but felt a bit lazy climbing up. The 4 blade is right now : ) Oh, and the top speed did not change, so who cares : )
Good explanation of how to prop out a boat! Just a comment on 4 blade vs. 3 blade propping. I found my boat would reach recommended WOT rpm early with normal load on board. Also, I do a lot of tubing and kneeboarding with the kids. Since I had headroom, I switched to a 4 bladed prop to get better traction on the water for water sports. Very satisfied with performance now. Happy side effect is better handling, especially in following seas. Having an extra blade in the water really seems to help. Losing a few mph at WOT is well worth it, especially since where I boat is very rarely calm enough to boat at WOT. Not sure what the fascination with top speed is all about anyway. I’ll take the quicker hole shot and improved performance any day.
Hey your article was very informative. I just re-propped my F115 Yamaha on a 22 foot fibreglass cuddy. Went from a SS three blade 17P to an alloy 4 blade 15P to gain better hole shot and more stern lift at a slow comfortable cruise around 15 knots. This helps keep the bow down so I get a better ride in the frequent 2 to 3 foot chop we get in my neck of the woods. Best economy still comes at 4000 rpm (22 knots). I only dropped 2 mph from my previous 36 mph top speed.
Back in the day when I bought my boat and had only passing knowledge of props I learned a tough lesson: The boat dealership doesn’t know a thing about props either. I did my own research, talked to Mercury and solved my own performance problems. Astonishing. I’ve been running a 5 blade Hi-Five steel prop for years on a carbureted 150 Merc, good hole shot and less top end speed. #cleanboat
2 things I think are important: 1) Motor height needs to be correct. Many outboards are mounted to low. Anti vent plate needs to be just skimming on top of the water at normal cruise 2) you really should be aiming for the middle point or higher of the max rpm range at WOT. hitting the lower half is marginal and easily further degraded by extra weight
I bought a new Sleekcraft some years back and didn’t know much about props. I had my boat at the dealer while someone was making a custom boat cover for it and someone with a boat just like mine told me my boat had the wrong prop. I changed props and it solved my cavatation problem while pulling up skier’s and had a fine top end too. Today I have a Glastron I have had just 3 months. After whatching and reading your website I switched to a four blade from three. The boat has excellent take off for water sports. Being a Chevy V-8 Volvo Penta outdrive I remember their advice on the RPMs. Though it will rev 6 easily, For extended crusing keep it about 3,000 RPMS
Thank you for the info. Just purchased a 175 HP Suzuki for re-powering a 2100 CC Sea Pro for fishing on the Sea of Cortez, BCS. They give a standard prop with the motor. Before it had a 140 HP Suzuki which I sold. The boat is rated for a 200 HP. I will start the standard prop and hope it is a good match. You provided enough information I can kind of gauge if the prop is functioning well. Like your website allot.
Great vid 👍🏻. I had a major issue with ventilation as my boat has a 20″ motor vs the required 25″. The 3 blade aluminum prop would ventilate real bad as soon as the boat came on a plane, and since my motor was already installed on the lowest setting I had 4 options: convert my 115 mercury to a 25″, cut my transom and drill new holes, add an engine bracket, or changing to a 4 blade SS prop with some decent rake. Swapping from a Black Max 3X13X19 prop to a Solas SS 4X13X19 was my solution and has eliminated 95% of my ventilation issues. Boat runs perfect now, comes up on to a plane real fast and my top speed has gone from 33mph to 46mph. #cleanboat
I think(from perusal this) I might finally understand something that’s been puzzling me for some time. I have a 150hp mercury on a 20ft wellcraft w/a 4 blade prop. That was the setup when I got it and haven’t changed it. Never used 4 blade before, just assumed it was like airplanes (to help balance ). Don’t remember any other boats being so twitchy. Better at pushing back at waves but before you make any significant speed change warn the passengers. Never had one that practically jumps out of the water and lands on a plane like this one does. Thought it acted more like a ski boat than a fishing boat. I suspected either the prop or the development of mental illness. Thanks for the clarification, I feel better.
Thank you for confirming what I was thinking. I had to replace a prop last season. It was the first replacement in about 10 years. I let the shop know i was struggling with planing when the family is on-board. He switched me to a 4 blade and i cannot believe the difference. The top end speed is lower by about 3 MPH but the hole shot is 5 seconds faster with everyone on-board. perusal your article today during the discussion of the added weight that my kids are all adults now and have added weight to my boat. Switching from 3 blades to 4 made the difference.
Thanks for the info. I’ve been researching the difference between the 2 and from what I’ve seen, I’d rather go with 4 blade prop. I like how you can get on plane faster, stay on plane at lower speeds, and have better control. Top end speed is not a big deal to me. Especially if it is only 2 mph less.
I’m running a 525SC built to 600 hp at the crank on a 1985 Carrera elite. I am running a bravo 1 outdrive with a nose cone and low water pick ups, a drive shower and external hydraulic steering. I have been running a 26p 4 blade. It gives me a great hole shot and gives tremendous stern lift. I experience mild porpoising from 20-30 mph but once I reach 30 I can drop down in speed w/o porpoising. I tried a 3 blade 27 pitch propand it eliminated the porpoising and gave the boat the ability to make sharper turns at 30-40mph, but the hole shot was slower and the prop would blow out if you gave it to much power on the hole shot. Running in the 50-55 mph range I was experiencing more prop slip with the 3 blade prop. I had less stern lift. I have yet to be able to run at wot. The engine isn’t getting enough fuel When pushing 3900 rpm it will start to backfire. We are leaning to the in tank pickup lines being to small of a diameter. The boat originally had a Volvo Penta 290A setup and the fuel tanks and pick ups are original to the boat. I guess the point of all of this explanation is that in my case so far, the four blade runs faster than the 3 blade at the same rpm. I don’t know if this will hold true when I can get to 5200 rpm. I would love to hear back from anyone that has ran a similar setup on a Carrera elite.
Good general info but I was hoping for prop math. Everybody knows under perfect conditions every pitch is worth 200 rpm. Where people mess up. They forget that every inch of diameter is worth 500 rpm. Going 3 to 4 blade drops an extra 200 rpm. Aluminum to stainless same pitch blade count and diameter 3 to 5 mph increase.
1990 whaler walkaround WD ( whaler sea drive bracket) with twin 1993 200 hp yamaha precision blend 2-strokes, running 14 1/2 x 17’s 3 blade stainless steel yamaha props, 225 gallons of fuel, gear, turns 4800 with engines down WOT with 3 heavier people (approx 850 lbs), trims up to 51 to 5200, tops out 38+ to 41.2 knots depending on the trim and current. I believe it is set up correctly. Cruising 26-27 knots at 4k-4200. Put on a pair of the SE400 hydrafoils which are great no more or very little if any ventilation in a rough sea / fast current. Love the engines and Hydrafoils were a great investment! I wonder what she may cruise at / or/ WOT WITH TWIN Suzuki 300 dual props?
That’s a good starting point. BUT you can have 2 three blade props with a different blade shape one will be better. The weight of the boat makes a difference. My boat is really light to the point I take on fuel as ballast in rough seas so it doesn’t tip over, loading when out of fuel I have to stand in the middle to load it,. So I use an aggressive 21p meant for an IO.
It can get a little tricky if you repower a bpat designed for 2 strokes with four strokes. Only tried on boats with up to 3 engines personally, but jeeze it can get expensive buying the different props for each trial and error. Especially if the hull has a huge step as well. That seemed to add another big variable. Maybe if you repower, you should leave a reserve of like $1k per engine for propping.
Nice article. Thanks. Just taking a chance, and taking this same chance on a lot of forums as well. I have a 1970 Mercury 1350. Finding a prop for this engine is a headache and a half. It’s got a 3 blade prop on it now, but would love to go 4 blade on it. It does feel like the current prop I have is a tad to big for the engine as it struggles to get on high RPM when pulling someone on Ski’s. It almost sounds like it has a dead spot, but after perusal this article I think I know what the issue is. Prop pitch might be to high. When not pulling I have no issue with the prop and the boat really jumps out of the water. You don’t maybe have a link to a website or any specs on which 4 blade prop would work on this particular engine?
Another article that makes me wanna do a day camp there. I wonder of my C340 has the best prop setup. I’ve had it at 50mph WOT mid to light chop. And it gets about 1.2 mpg at 32knts (I need to double-check that again) #cleanboat -but if I win I’m gonna donate it to another of your subscribers 🤣. I don’t do the cleaning
Hi, I’m wondering if the manufacturer picked the wrong prop for me. I have a 25’ step hull with a 23p factory stainless steel prop. It’s a LH prop with leaning to port most of the time with balancing issues. The battery is on the drivers side now. My last passenger was about 25lbs heavier than me and it was still leaving more so to port. Do I need a RH 23p stainless steel prop? Or a skeg anode slightly turned towards the driver side? The current anode is just flat. Maybe trim tabs although I don’t want to effect top speed if possible? Maybe a cavitation plate???
Great vid! Thank you very much! Can you add some information about props for sailboats? Arround here, we sail in a wide river with pretty strong currents. Those two blade props just can’t do the work. Many change the 2 blade for a 3 blade. Would you think a four blade would do better? Thank you very much anyway.
Almost every used boat I bought was over-propped. In a perfect world you want a ‘square-wheel’. A 13×13 is a square wheel. An inch of pitch buys around 200 rpm. if I remember correctly. Cup can vary but has the equivalent of 2 inches. A barge wheel pushes a heavy load like a sailboat. A faster pitch is wanted for top end and cruising. A variable pitch prop is a thing of beauty. If you can’t hit the right revs. you are over. If you can over-rev then you are under. Don’t ‘lug’ your engine. Find the sweet spot instead. You’ll be glad you did.
And don’t forget that changing your prop and pitch will also change the how quickly you get up on plane and speed at idle. I’m not sure if the speed to cruise at plane is different, but i do know the rpm is different on my underpropped 4 blade (14x17x4) versus my correctly setup 3 (14x19x3) blade. I’m sure this affects my mpg (or gallons per mile for you big boat guys). my idle speed dropped from 5mph to 3mph, which means i usually have to give my 4.3L v6 a little throttle while in an idle zone. (1992 Chapparel 1900 19′)
I have a ski boat with a beat up old 13×13 prop 3 blade and it seems to not Rev out to the right rpm. The engine in a 305 and tired. The original engine was a 350 with a 13×12 3 blade.. so my question is if I put a 4 blade what pitch should I try first. I was thinking a 12×12. I never use wot because the motor is tired. I want to cruise at a lower rpm and get good mpg.. but also be able to pull big people up out of the water as I struggled a bit with a 250lb skiier.
4:11 yeah but no actually not… the vent holes in the prop let exhaust gas out of the holes. this creates a controlled slip since the prop is now trying to spin in a stream of air instead of water. that little bit of slip allows the prop to spin up faster getting you on plane faster. its just like revving the engine in a car and dropping the clutch.
Back in the day, when I was a kid racing a three-point hydro with a Mercury Mark 20H on back, two-blade props were the way to go. Took longer to get on plane but once there would easily beat a similar boat with a three-blade prop. The trick was to get the right combination of pitch and diameter so the engine could rev higher.
16 ft flasts boat 90 horse Yamaha had a 3 blade 17 pitch prop was bouncing off the rev limiter went to it 3 blade 21 pitch and top ends good but lost The whole shot. It is vinted with quarter inch vent holes would it help to open up the vent holes. Also is porpoising hard once I start trimming it out. I also am running a jack plate.
I have a 1986 smoker craft sled, and I had to repower the boat. I went to my local Mercury dealer they sold me on a prop instead of a jet pump. I had to take it out and put 2 hours on the motor, and the boat had a hard time getting up on a plane.\r Now it’s 7 months later, and I am in the process of reducing the pitch from 13 to 11. The dealer said it would help the boat get up on a plane. Why didn’t the dealership deal with this problem when they sold me the motor? They should have added a new motor, picked out the prop they thought would work and go try it out for me. This motor was the most expensive motor I have ever bought – around $9000.00. An unhappy Mercury motor owner. \r \r Dave C
i found that my boat (17 foot proline – with a bracket – 90hp outboard) runs best with a 12 1/2 pitch prop – but they only sell 12 or 13 ( i had my 12.5 made, but broke it on some rocks) – this is the first time i’ve ever heard about venting – do you think i could drill some holes in a 13p and get it closer to the 12.5p performance?
I talked to a mechanic one time and he told me about this bahama 41 owner who spent like the whole day testing props, spending like $2,000 in fuel and at the end of the day he asked if they took trade-ins on propellers. Also, how about those guys who tune verados to rev like 7,500 rpm? I’m sure those engines will last long and not require an oil change after 20 hours.
I have a robalo r200 dry weight 3000( loaded ~5000-6000), it came with a Yamaha 150 and the prop is an aluminum 14 1/2 x 17, having a hard time getting on plain when loaded with scuba equipment, the Yamaha propeller selector website recommended SS ULTIMA 4 prop ( Stainless 4 blades 141/4 x 17), I think is and smart move based on your article… I would like to see some ideas about it…. thanks.
A few things you didn’t mention. Each change in prop pitch is a 300 to 400 RPM change. For example if you go from a 19P to a 20P you have dropped RPM’s 300 to 400 . If you go from a 3 blade to a 4 blade, you MUST drop 1 to 2 pitch sizes to keep RPM’s at the same range. Vent holes are ONLY for getting on plane. They DO NOT effect performance at speeds above boat plane. They allow exhaust gasses to exit the prop in front of the blade allowing the prop to spin up to a higher RPM as the boat tries to break over onto plane.
#Cleanboat Another great article. I went through the prop selection process with my boat a couple years ago. My boat is now propped exactly as described in the article. Alone with light fuel and no trim I can touch the rev limiter. With a normal load of fuel, people, and gear I can still achieve max RPMs near the top of my manufacturer’s suggested rev range. I also went from 3 to 4 blades since my boat required stern lift. Hole shot and mid range are amazing with any load and I only lost 4-5 mph on the top end overall.
I disagree with your comments on the purpose ventilation holes in the prop. They do not allow water to flow through the prop without being pushed by the prop blades. They allow exhaust gasses to ventilate the prop slightly when you are planning out the boat. This gets the rpm up slightly, giving you a little more horsepower to plane the boat quicker. At WOT the velocity of the water moving across the holes basically seals off the holes so they have zero effect at WOT.
How about a 17 ft boat with a honda 90 vtec spinning only 5400 rpm s trimmed optimally. ?, it should be spinning 5800. It takes long to get on this 5400 rpm, it feels like there should be more torque or this prop is to big. Now there is a 13.1/4 x 17 3blade oem honda prop. The boat weighs about 1800 to 1900 pounds with us 2 on board.
3-Blade Propellers\r \r Higher top speed: 3-blade propellers generally have a higher top speed than 4-blade propellers.\r Better acceleration: 3-blade propellers also have better acceleration than 4-blade propellers.\r Less drag: 3-blade propellers have less drag than 4-blade propellers, which can lead to improved fuel efficiency.\r More efficient at higher speeds: 3-blade propellers are more efficient at higher speeds than 4-blade propellers.\r 4-Blade Propellers\r \r Better handling: 4-blade propellers provide better handling and stability, especially at low speeds.\r More grip in the water: 4-blade propellers have more grip in the water than 3-blade propellers, which can be beneficial for boats that are used for towing or carrying heavy loads.\r More efficient at lower speeds: 4-blade propellers are more efficient at lower speeds than 3-blade propellers.
I have a 14’ twin vee with a 70 hp Yamaha. So plenty power. I have a 3 blade prop. I’m good at trolling speed and planing speed but cruising speed I get a ton of ventilation. I usually fish with it and have a decent amount of weight on the boat. Will a Yamaha Fx4 Prop – 4 Blade 13.25X14Rh help me reduce the motor ventilation. I don’t care about top end speed. I usually don’t have the sea conditions to go wide open. Please advise on this I really appreciate the input! Mahalo
I have a 27 foot Carver Santego but added a lot of weight to it for live aboard. The stock props wouldn’t get it on plane with the added weight so I used flatter props as you said. I lost some fuel economy but got on plane. Now I’m adding a solar panel array and big batteries so I’ll never get on plane with all that weight and want props to increase fuel economy at 6 knots which is where the boat just starts to throw up a bigger wake. Should I go with the maximum pitch I can find? Four blades instead of three? What helps most for increasing my range at 6 knots? Can you have too much pitch for low speed?
Question: I have a Baronette 16ft cabin boat, a 90hp 3 cylinder Mariner motor probably 1990 model. I slalom waterski, what prop should I use I am 90kg I need some power to get me out on slalom and then ski at about 55km/h. Suggestion will be appreciated. Fresh water, and I have a Hydrofoil on my motor.
Any recommendation for a prop for a pursuit 325 os, twin yamaha 300 about 15k lbs loaded. It comes with 3 blade 15.5 x 17. Was looking to get a 4 blade prop to get better mid range fuel economy. I am ok with losing top speed. Was thinking a 16×16 maybe or do you think I should go to a like a 15×16 or any other recommendations for better fuel economy?
I recently went from a 150hp 2 stroke Merc. to a 200hp 4 stroke Suzuki, on my 21′ cc Sea Pro. It seams to get up on plane quicker but top end speed is about the same 50mph. The RPM rev limit is 6100, top speed rpm is 6000. 3 blade prop with 21 pitch. Full tank of fuel 70 gal. & just 1 180lb person. Any idea why its not getting more top end speed ?
I have a 2004 17 foot dusky with a 2004 merc 90 2 stroke. Currently has a quicksilver 3 blade 13×19 and it’s sluggish to plane with 3 people and gear but does get up and hit 34 mph around 4500 rpm. Cruise 20 mph at 3800 rpm after planing. Looking at a turning point 4 blade. Not worried about top speed. Looking for quicker hole shot. Should I stick with 13×19?
I’m about to order a new prop for my Key West 210 Bay Reef with a Yamaha 250 SHO. Currently has a 15.25″ X 19P Powertech OFS3. Fully loaded with fuel, 4 people, 4 batteries, TM, and fishing gear, I’m hitting the rev limiter at approximately 60 MPH. Looking at upping to a 21P. Does this sound accurate to you? #cleanboat
My 16 foot Caravelle with a 40hp outboard wouldn’t plane. A prior owner had cut down the transom and the motor sat too low. I bolted on a whale tale and the combo worked great. All these comments about people with their 30 foot tri motor set up and here I am with a boat I got in trade for a car I’d bought for $450. lol
I recently just went to a 4 blade stainless steel prop from a 3 blade aluminum. After install and getting it on the water, I have this horrible rattling noise at low idle in gear (forward or reverse). Sounds like a bag of rocks! As soon as I apply a little throttle, the noise goes away and it sounds normal. Specs: Mercury 150 4 stroke, Turning point Mach 4 Express 13X15.25 Stainless. Old prop: Mercury OEM 15X15. Any ideas?
4 blade is more for power a three blade is more speed a 2 blade is a true speed prop theoretical a 1 Slade is but not ballenced,it also has to do with weight style of hull horsepower and intended use a heavy work boat low horsepower vs light same HP. Now old tug boats at 100 horse power can move a ship around with 100 dress of tuns of weight. With no wind or current a man can push a ochen liner away of the dock carbon buildup is dirty unburnt fuel,I can run an engine at 2000 rpm as long as timing and good fuel is used fore years and have no carbon buildup, wheat carbon buildup hurts is valve seats and piston rings.most diesel engines loaf along at 2500 rpm all day and decades long with no problem!
1990 21 pursuit cc. 1989 220 excel Yamaha. 3 blade 14 1/4 18p 5100 rpm prop tech. 3 blade 14 1/4 17p 5700 rpm solas. Same top end of 47mph. They are expensive and ppl in s Florida don’t like to barter. Solas is vented prop tech is not. Love the cruise speed of the prop tech 30mph @ 3500rpm. Stock prop that came with is a 13 3/4 19p. Only get 4800rpm. 45mph wot
We are creating a ‘kayak’ site for marine/boating parts and accessories to help people find the best deal vs. having to go to lots of individual stores to research – we may also provide links to content on youtube such as yours so people can also get advice. What do you think about this idea? Do you think it is a good idea for yourself/your audience? We would like to get some feedback before we get too far down the road. If you do like it, is it the kind of site that you would feel comfortable advising your audience to check out? Thanks! Cheers, Steven
This sounds like terrible advise, I’m sorry, but like you guys don’t know what you’re doing. You should never prop it near the top of the RPM range with a load but near the bottom for best cruising & top end speed & fuel economy. As long as a planing hull has no problem getting up on step, near the bottom you go faster at cruise and at wide open throttle, with better mileage. Just keep it from going below the bottom of the range when fully loaded. If alone and with half a tank, your 5,400 RPM was about right…and you shouldn’t get a bigger prop on a full planing boat like that to bring down the RPM but get more pitch or a prop with more cupping!