The Correct Prop For Your Boat! How To Know!

[@BornAgainBoating]

Learn To Work On Boats with Step-By-Step Video Courses @ BornAgainBoating.com

[@robertbain5076]

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.

[@barrybebenek8691]

Did you change the pitch (down) when going to the 4 blade? Or keep it the same as the 3 blade? 🇨🇦

[@Bikes_N_Adventure]

Couldn't agree more, 4 blade, two pitches down is the way to go!

[@Bikes_N_Adventure]

@@barrybebenek8691 I went down two pitches

[@codysmith605]

i put a nice four blade stainless prop on my tow boat and it cut a good three or four knots off my top speed i didnt like it put the old three back on this is a work boat and an extra four knots is good to have

[@gbass7328]

This is the best prop advise. No one talks about WOT, rev limits and trim and low vs high loads. That's a lot of variables but if you listen closely, he tells you what you want to end up with. Basically, don't over prop the motor.

[@ben3989]

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

[@mikewhite6108]

Your spot on with your information. I owned a prop shop for 9 years. And that's exactly what I used to tell my customers when figuring out the correct one to use.

[@BornAgainBoating]

Thanks for sharing

[@gatgolf]

I know it's been 2 years, I hope you can still answer. Is it generally accepted that when determining your rpm at wot, you should keep the engine trimmed down?

[@legacyserviceprofessionals6955]

No, you want to trip up to achieve you top speed and top RPM for that speed the way you would normally drive the boat with the amount of weight in the boat that you would normally be carrying. If you propped it for proper RMP with out lifting the trim during your run you would not be able to lift your trim during regular use with out getting your rpm’s too high. During your prop testing, Load your boat and run it just like you would normally be using it.

[@DrKnowNothing1]

Propping out a boat at typical load is ideal, but not always practical. The video recommends propping while trimmed down if the boat is empty. So you’ll have room to trim up to compensate for additional load.

[@ghettohey2388]

When it comes to 3 or 4 blade props its simple. You want more speed/performace then go with 3 blade. You want better control, handling, more power, better hole shots with fully loaded boat then go with 4 blade.

[@TheBeingReal]

I went to a 4x4 prop set on my Bravo-III’s dropping 2” of pitch also. Running twin 350 MAG MPI’s. Huge difference in stern lift, less bow rise ans suprisingly less engine noise too!

[@brocluno01]

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 : )

[@maxxgraphix]

Same here. 4 blade big hole shot, better control same top end. Fuel economy improved too.

[@fredself9838]

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

[@wesgrindstaff79]

Good video, but one point you described incorrectly was about the prop vent holes. These are to allow for exhaust gasses to escape around the prop during holeshot to allow the engine rpms to increase. As well as having little to no effect once on plane.

[@flash521]

Thank you for the info. Just purchased a 175 HP Suzuki for re-powering a 2100 CC Sea Pro (2004) 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 channel allot.

[@BornAgainBoating]

Good luck!

[@arfrunningbear7022]

Two friends had identical bass boats and motors, one had a three blade prop, the other had four blades, hole shot was identical, four blade prop was one MPH faster.

[@georgevidas8256]

Hey your video 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.

[@joshgtheog3371]

i would love to see a video on hydrofoils and what they do for your boat and how they work

[@u433274]

JOSH G THE OG Permatrim.com. Permatrim plates are the best and I have used most all of the others in my many years of boating. Currently I have one on my 17 foot skiff with a 90 Yamaha and one on my 24 foot Triton bay boat. It’s amazing the difference it makes.

[@davidbrymer1230]

Great explanation. Now it all makes sense why the previous owner of the Flats boat I just purchased installed a different prop and why the boat hole shots like a champ. #cleanboat

[@markrobbins9552]

I think(from watching 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.

[@davedodge7761]

Have a 19 ft cuddy. 5.7 Chevy. Went from a 15 17 to a 14.5 19. What a diff. Better mid range n more top end. N a wicked holeshot. The prob lasted one trip. So excited on performance that I forgot to lift out drive n it didn't like cement. Fubar... lol

[@BornAgainBoating]

Ouch!

[@davedodge7761]

@@BornAgainBoating oya. 170 down the pipe. Bam

[@FriViden]

For acceleration Mercury Enertia, for most efficient Mercury Enertia ECO. Tried them both. Only weakness - vibration at low speed rev below 800 rev/min.

[@NM-eo1xd]

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

[@edwardnelson6]

N M What kind of boat? I have a 115 Mercury 4 stroke, on a 19’ Mako Skiff.. Stock aluminum prop, thinking of SS.

[@NM-eo1xd]

edwardnelson6 Hi It’s a Sportsman -Island reef 19ft. I already had the motor (2013 model) and the dealer said that the 20” motor would work great with that boat. So bought the boat from Florida and shipped it to HongKong, then found out it was too short, and that’s how I ended up going with the 4 blade SS. I would recommend the switch to a 4 blade SS for overall performance, but if the standard one u have works well then it might not be necessary to change. Would be great if u can test a prop before you buy it allowing you to make a “PROP”er decision.

[@kevinhirdes8097]

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. watching your video 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.

[@runbmc35]

On a 19' sea ray wirh a 3 blade 21p, i could get about 45mph at about 5,000rpms. That seems pretty efficient based on my boat only having a 4cyl engine. I did not expect to ever get going that fast when I purchased the boat

[@seanwolfe8046]

Great video! I know this was a prop subject but you failed to mention dole fins can solve out of the hole issues without changing the prop. I do say, they are ugly and lower your top speed but can save trial and error time. Haul out fees are rough.

[@kh2140]

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.

[@kh2140]

I tried a 4 blade and found out the 3 blade was better. Maybe because it was in a river, but the 4 blade felt like it struggled when the 3 blade was smooth.

[@MasteroftheBlaster]

Does anyone have prop suggestions for a 2021 Trophy T20CX with factory 150hp 4 stroke? Sorry but I just bought this boat and don't have the engine specs.

[@Floordford]

Man I need to move to the coast. These boating videos are giving me the fever.

[@stinkfist57]

I really appreciate the fact that you use the proper term, "engine".

[@stinkfist57]

@@SeanPennII incorrect sir.

[@vic1sch]

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.

[@BornAgainBoating]

Most of the time people running a race engine like that have a 5 blade prop on it, but it all depends on what you are trying to do.

[@vic1sch]

@@BornAgainBoating right now with the 4 blade I have a slip rate of 7 at lower speeds 20-40 and 5 at higher 40 up to 62 mph at 4000 rpm which is the fastest I've gotten because of fuel delivery problems. The in tank pickups are original with the boat and I think the diameter is to small so we will be changing them out this winter. One other thing is the weight of the boat originally as listed in nada was 2300 lbs. I did compare that to a donzi classic 22 which listed in nada at 3500 and on donzi's site list it at 3725. My mechanic said that we gained no more 80lbs because the bbc weighed more than the sbc, but the bravo 1 outdrive was lighter than the Volvo Penta 290. Carrera went out of business in 2002 and was bought out by aftershock that also went out of business, it is hard to find exact specs on my boat. This is not Carrera power boats out of Florida. My boat was manufactured in California. My center line of prop is 5 1/2" below the bottom of the boat. My mechanic said if I wanted to go strictly for speed he would have brought it up another 1". We use the boat mainly for recreation, water skiing, wakeboarding and pulling a water rocket for the grandkids. I also like to take it to lake Powell. With my old setup. My rpms would about match my speed, 3500 rpm, 35 mph however at 5200 rpm it would be about 45-48. Now I can run at 45 mph at just under 2900 rpm. As it sits right now, I am not running any trim tabs and the boat handles extremely well. That may change as we get the fuel supply problem figured out and the speed increases. Also reading about 5 blade props I came across this. www.mercuryracing.com/prop-school-part-5-blade-efficiency/ We did raise the x dimension, but I don't have a stepped hull and my prop is not running totally surfaced if it's piercing the surface at all.

[@thisismyalt9010]

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.

[@Rick_Sanchez_C137_]

ThisIs MyAlt The words you are typing look like English.... but the sentences all sound Greek or polish or something....

[@townsville69]

I recently changed my prop for my 2012 yammy 2 stroke. Its like a whole new motor. Gets out of the hole quicker, lower rpms for same speed and way better fuel economy. I wish I replaced it years ago #cleanboat.

[@profthomason]

Is that Townsville FNQ?

[@townsville69]

@@profthomason the one and only Brownsville.

[@mikeries8549]

Outlaw Oosers High Performance Tillers on facebook. Cool group. #55

[@erikb8877]

A good rule of thumb I have always used is, just me in the boat, 1/2 tank of fuel, no gear and just barely kissing the rev limiter when fully trimmed at WOT.

[@Rmann327]

What would prop would you recommended for a 12,000lb, 28' length, 11' beam, direct drive boat? It is from 1983. It comes with a 3 fin prop but most of the comments make it seem like a 4 fin prop would be best. The boat is in the San Juan islands in Washington state

[@BornAgainBoating]

I really don't know you gotta do that calculations and trials to figure it out, here's some more info on that: kzbin.info/www/bejne/gZKQdXmAm7uKa7M&t

[@fatdaddy6512]

I put a 3 blade 21-pitch on my boat with 150 horse Merc comes right out of the hole very fast and the boat goes very fast I just need to stop destroying them on the rocks

[@M_A_C_K_WA]

Isn’t 3 prop meant for speed and 4 - 6 prop helps with the boat getting on plain quicker and helps with towing quicker?

[@M_A_C_K_WA]

And helps to get to places quicker with height?

[@jeffbryner5355]

At 500 a prop on the cheap end its a alot of money for trial amd error. Especially if u got a power boat with props that are 5k each lol

[@craigbielsky115]

when you can afford the boat that runs 5k props you dont have to guess we know .....

[@timlong1462]

Seems like prop manufactures should have a rental program or trial props that are used. You break it you buy it, or return in a week and get your money back and try a different one.

[@jeffbryner5355]

@@timlong1462 that's a great idea actually. I would love to try something new on my boat but it gets expensive quick to see if it maybe improves your performance or not

[@timlong1462]

@@jeffbryner5355 I’m surprised it doesn’t exist actually. Seems like it’s needed with hundreds of comparison videos and info that never seems to be the exact comparison you need for your specific scenario

[@jeffbryner5355]

@@timlong1462 yep exactly.

[@bruced566]

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?

[@jrodtfr9004]

Man I've watched a lot of different prop videos and boating videos in general and none of them come close to the ease of understanding and clarity of explanation. Very helpful because I am upgrading my prop right now and this video just put me right where i need to be.thank you. #cleanboat

[@youdonthavetoreadthispost.5850]

Almost every used boat I bought was over-propped. In a perfect world you want a 'square-wheel'. A 13x13 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.

[@davidhenry4634]

What size prop will you recommend for a speed boat (25ft/28ft) having a Yamaha 250 with a max allowed speed of 60 mph and 3 race crew members , and a fuel capacity of 120 litres.

[@esthersmith1412]

Yup perfect timing here too. Doing work on my boat trying to fix steering. Noticed problems with my top end rpm so I know I need to change the prop. Great KZbin channel guys. #cleanboat

[@craigbielsky115]

WHAT IF THE MOTOR IS NOT UP TO POWER ?NOW YOUR JUST PUTTING A BANDAID ON A PROBLEM.... MAKE SURE MOTOR IS RUNNING CORRECTLY FIRST

[@davesboatingfishing]

Interesting video and factual. I've got a 4 blade adjustable pitch prop on my boat. I set the pitch lower for more load ( people), handy to have . One prop adjustable.

[@ericderace]

What about buying an aftermarket prop vs buying OEM? Does it really make a difference in performance?

[@robertchandler5055]

you are killing me smalls ...its late december 2020 and you are talking about hope your Christmas was ok i really thought i missed christmas somehow!!!!!

[@molon_labe_arizona]

Wow. That was extremely informative. Well done. Will have to watch several times through

[@simulatedpilot3441]

Ahh spun mine today on the dirty James River relaxing waiting on Towboat lol

[@matthewsaia409]

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.

[@brandonhebert5485]

That's right. When he got to that point in the video I wondered just how much this guy knows about props. Those vent holes allow air to be forced over the blades, that air is engine exhaust and will allow for a slightly higher rpm. It's kinda like cheating.

[@theborg269x]

I have a ski boat with a beat up old 13x13 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 13x12 3 blade.. so my question is if I put a 4 blade what pitch should I try first. I was thinking a 12x12. 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.

[@blackknight2072]

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']

[@Dwq47]

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???

[@raullopez4617]

Happy new year from Spain. Always is a pleasure to learn with yours videos.

[@scottsmith2869]

One more thing I have noticed on my last two boats. There in-board/out-boards. The tach is almost exactly what the RPM reads.

[@craigbielsky115]

THATS WHAT THE TACH DOES LOL YOU MEAN SPEEDO?

[@mythicgamingmk1105]

What about a 300 hp Mercury racing engine which can use a 5 blade propeller

[@TheDoug9901]

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.

[@socore4659]

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.

[@gypana]

I swapped 3 blade to 4 blades on my cat, it dropped about 3 knots top end but stays within the revs at WOT..it grips the water better now and feels like a different boat offshore....the 3 blade props were 17 inch and the 4 blade are 15.

[@gypana]

@@IFish4Tuna pitch

[@gypana]

@@IFish4Tuna Yeah mate I wish I could answer that for you but my boat isn't equipped with smart gauges, it's 2007 model running twin 90 etec's that had the standard Viper props on them I think they were 13 1/4 X 17 and now I'm running 13 1/4 X 15 4 blade just off memory but I haven't been on my boat in months as it's garaged near the boat ramp and we at locked down here in Australia at the moment. I think the 4 blades could even be a 14 inch diameter, I just can't remember but with the fuel usage I haven't noticed anything significant but with performance though it gets up on plane faster and holds there at lower RPM's it also tracks and feels better offshore especially when the seas are up and you're off and on the throttles.

[@gypana]

@@IFish4Tuna You'll definitely noticed the difference...let us know when you do.

[@AccordionJoe1]

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.

[@thefishinpolock]

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.

[@craigbielsky115]

wrong.... each 1 inch change is 200 rpm so from 17 -19 is 400 rpm 19 - 20 is only 200rpm i have seen as little as 100 rpm difference from 3 -4 blades and as much as 500 rpm so testing is still needed its not a standard change specially if we move motor up on transom 1 or 2 holes....for the 4 blade.

[@reddawng43x91]

Incorrect! It’s approximately 150-200 max

[@alexpb9]

Nice video. 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 watching this video 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?

[@delta182]

#cleanboat ... whole shot is my pick..Happy New Prop everyone

[@tclark8800]

I need to know which inner thrust washer is needed for a 04 90hp Yamaha to run a 4 blade trophy sport.

[@BornAgainBoating]

Trial and Error my friend, as far as I can tell the Trophy Sports are more for 40-60HP engines and come with the Flo-Torq 2 or Reflex Hubs, which come with the thrust washers. But you'll have to figure out based on the hub that is in the prop what thrust washers you'll need. Best bet would be to swing by a marina or dealer that has a decent parts department and play around with hub sets and washers there in person to figure out a set that will work ;) pretty standard washers though, so you should be able to figure it out :)

[@timrainger8908]

If I was going 3 blade to 4 blade. My current prop is a 13x19 on a 17.5 ft Edgewater with a Yami V4 115 2 stroke. Im looking for better low/midrange performance what size would you choose? 13x17 13.4x15 12.5x19 Thanks!

[@BornAgainBoating]

I'm not sure, the 13X17 would be the place to start, but I'm not so sure about that exact set up because there are a lot of other variables, this video should help: kzbin.info/www/bejne/gZKQdXmAm7uKa7M&t As well as this: kzbin.info/www/bejne/iH7RgadrYr92rJI

[@alanadams9686]

The manufacture/dealer done an awesome job on propping out both our pontoon boat and bass boat. Didn't need to change anything. #Cleanboat

[@BornAgainBoating]

Congratulations @Alan Adams you're this weeks winner! Shoot us an email or a DM with your shipping info and we'll get your cleaning supplies sent out! Congratulations and thank you for your support!

[@8180634]

Great videos! Would you please consider doing one on descaling an outboard, such as by flushing with Barnacle Buster or any of the other similar chemicals, or whatever method you think works best?

[@dwightbernheimer331]

Let's stop all the bullshit... in today's buying Market most dealers are going to make you buy two or three props to get it right they're not going to give you $500 props to try... 80 years old mom had me on a boat before I could walk LOL 'Nuff said!!!... thanks for posting

[@omandipr]

hello, question I have 200 yamaha with14.5 15 prop, what otherthank you in advance choices I have?

[@Wond3rland___]

How do I know if I’m in the right rpm range?

[@brianreffner3548]

I have a 5.7 in my boat with a wot at 4400 to 4800. How long g can I run my boat in that high rpm range

[@richardlovas9541]

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.

[@BornAgainBoating]

Idk about all the trimming, porpoising, and jack plate issues because all that is dealing with the mounting height of the engine, not necessarily anything with the prop. But, if you use those vents, that lets exhaust out of the prop and it helps create slip, which doesn't necessarily give you more hole shot. Usually slip doesn't equal grip. Grip is what you want for hole shot, that's why 4 blades usually gives you a better hole shot. Now, more than likely the diameter of the prop is what is going on, if the 17P was too small and you were hitting the rev limiter, if you had a better hole shot, the prop was probably a larger diameter prop, and the 21P might be a smaller diameter prop, which is why you lost hole shot.

[@nrglife6930]

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 video... I would like to see some ideas about it.... thanks.

[@BornAgainBoating]

Thank you for your question! Please post it in our Born Again Boating Community! Go here and scroll down to access - it’s free: www.bornagainboating.com/

[@reddawng43x91]

14.5x15 is what you need

[@rolandcornejo1145]

Hi. I have a 2003 wellcraft 250 fisherman with 250 Yamaha hdpi. Would you by any any chance know which prop would be best for my setup? I don’t understand this stuff and can really use your help Roland

[@scottbaxter5610]

At 4 minutes you talk about the vents on the prop I thought they where there for some exhaust to escape to help ventilate the prop a little at lower speed.

[@Ken-fisho]

Pretty concise information there Aaron but theres also blade shape and whether you tow as well good vid though Happy New Year mate 🇦🇺

[@BornAgainBoating]

Happy New Year! Yeah, I had "talk about cupping" written down, then it just never got into the video lol

[@Ken-fisho]

@@BornAgainBoating😃 not to worry i actually thought you mightve forgotten to mention it maybe caught up in Pre NYE party mode 🍾🥂🎆

[@markgippy]

Great info! Happy new year!

[@WhiteGangster400]

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.

[@BornAgainBoating]

Lol, yeah, but what's he going to do with the extra props lol Mercury's actually just came out with a bulletin a few months ago about warranty and altered PCM's. They've turned them up to like 450 or so! The OEM 400's turn 7K so 75's not too bad. They actually spun one up to like 12.5 I think at the factory, they said it started making some pretty funny noises lol

[@WhiteGangster400]

Born Again Boating oh yea I’m sure they know it’s a warranty void but some of these people ain’t afraid to spend money.

[@profthomason]

Happy New YEAR Mate!

[@buttlickbandit8465]

What about use 4 props? Could you use 2 different sets of props?

[@vxnova1]

Does this mean I should run the boat wide open? Or is it ok to cruise around at 4 to 5 k rpm, I’m on a small jet boat, yamaha sx190 and I hit planing speed between 4 and 5 k. No prop to change here though

[@BornAgainBoating]

You don't have to run wot all the time, 4-5K is usually most boats cruising speed so that's about the perfect RPM range! You do want to run wot occasionally though to burn off any carbon build up :)

[@vxnova1]

Born Again Boating thank you

[@dennislabrador3554]

Hello great vid.. i have a question for which is heavier yamaha 9.9hp 4strokes or mercury 9.9hp 4strokes? And which one is better for speed? Thanks!

[@BornAgainBoating]

I'm not sure on the weight, they should be really neck and neck and the speed will also be very similar, both are great engines.

[@dennislabrador3554]

@@BornAgainBoating thanks for the info

[@clacker54]

I never really thought about weight making that big of a difference. Good info. #cleanboat.

[@jrtonka19]

#cleanboat..awesome video cant wait for the 2020 videos.happy new year!

[@BornAgainBoating]

Suggest Topics That You Would Like For Us To Cover On Technician's Tuesday! www.bornagainboating.com/technicians-tuesday/

[@alibilgutay6004]

Thanks for sharing such videos for informing us. I also suggest that sharing info about refitting a boat. So we can deride whether buying a new boat or refitting an old one. Thanks...

[@kevinhirdes8097]

What is the difference between running an outboard verses and IO verses and inboard. I notice boats in Florida run multiple outboards while in the Great Lakes we tend to like I/Os or Inboards. We are looking for a new boat and i really would like a center console with an Inboard so the boat will run flatter through the water with the engine being more forward. Am I crazy? They are very hard to find.

[@alibilgutay6004]

Born Again Boating i mean does it worth refitting an old boat than buying a new one? Especially wiring and refitting interrior design are a way to have a new boat?

[@dumitruuncu5230]

@@alibilgutay6004 .....

[@micknjo1990]

How about a video on how to get a boat on to the pad

[@karelh186]

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.

[@BornAgainBoating]

You could go down to a 15 pitch prop and that will get you closer to 56 or 57, but for the hole shot, you could change over to a four blade

[@karelh186]

@@BornAgainBoating it goes 57 kms per hour right now with the 13/1/4 x 17 pitch, but i have the feeling i could get more out of a 90 horse. It comes out of the water fast enough for me and i don't do watersports, but i think the top end could be more, just because the slowly climbing of rpm's on the end and only 5400 instead of 5700- 5800... Or just let them chip this thing up to 100 hp, exactly the same engine🤔

[@josephlowrance3]

Got a 96 Mercury 2 stroke 115 ELPTO on a 1900 XR Maxum. I do have a problem currently with the top speed only being 25MPH. Aside from that what prop would be best for wakeboarding and not sacrificing all the top speed?

[@roughym7663]

Hi, love the videos. I’m looking for a reliable online store in the US to purchase a Rubex HR4 prop for my boat. It needs to be shipped to Anchorage. A lot of the sites don’t get such good reviews. Any advice please?

[@BornAgainBoating]

Since you know what prop you want, you might reach out to Solas and ask them where the best place to get one from would be! They should be able to point you to a dealer that can get you the prop

[@russwilkerson2741]

Bobby Soles propeller.com Riviera Beach Florida. They know their stuff. Used them since the 70s

[@harleydad1975]

I have a 2004 17 foot dusky with a 2004 merc 90 2 stroke. Currently has a quicksilver 3 blade 13x19 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 13x19?

[@tpenberthy]

Hey Will, I run a Evinrude 115 in a 17' "Fish/Ski" runabout (Stratos 476FS) and last year switched from a 3 blade (11x19) to 4 blade (13x17) because of a similar sluggishness to plane. I often have a full boat, and the 4 blade I put on made the hole shot amazing, and my top speed only went from 45 to 42 (with a tailwind going down river ;). I almost never run flat out, so the trade off barely even counts as a trade off for me.

[@harleydad1975]

@@tpenberthy Thanks sir. I'm going for it!

[@tpenberthy]

Hey Will, quick update. I switched back to my 3 blade 13x19 (for science!) and have new appreciation(s) to share: - hole shot improvement on the 4 blade is super noticeable - almost effortless with 4 blades (even with a full boat), but "do we need to move weight to the front?" slow with 3 blades, even with just 2 people on board. - top end speeds: 42.2 mph (4 blade) 48.1 mph (3 blade) Same stretch of water, same basic wind. The 3 blade is at LEAST that much better at high speed. It felt to me like (with more trim finesse) I could have hit 49 for sure, maybe creeped up to 50-51. Verdict for me: I'm going back to the 4 blade bc I want the hole shot and more efficient middle rpm cruising, but 3 blades certainly makes a speed difference.

[@harleydad1975]

@@tpenberthy Great info. I'm in South Florida and sometimes the water is rough and the hole shot is more important than top speed.

[@markdunar2121]

Can you run a salt water 2000 290 sea ray sundancer in fresh water engines have 350 hrs

[@carlpourciaux3734]

What a great explanation on props... good stuff

[@ethosmgtowlogos9893]

Been working on a proper size for my 5.6 meter RIB, thanks for the help! #cleanboat

[@Kauaiboy13]

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

[@BornAgainBoating]

I emailed you

[@craigbielsky115]

TRIM IS TOO HIGH OR MOTOR IS MOUNTED TO HIGH

[@wyattsdad8561]

Wouldn’t the prop that comes with the boat be the best? Wouldn’t they have figured out what is the best one for the motor and the hull shape?

[@craigbielsky115]

the boats get set up by guys at the dealership....you would think they could get close but sometimes its as simple as putting whatever they have in stock at the time on if its within the rpm range could be low could be high ....boats dont come from factory with props they are installed by the dealership. users and gear can vary so there isnt one correct prop did you watch the video?

[@wyattsdad8561]

@@craigbielsky115 oh okay 👌 I’ve always wondered if there was a better prop for my 130 hp merc on my 02 Bayliner classic 1950

[@jmartin929]

@@wyattsdad8561 did you ever find a better prop for your 3.0 merc? I'm getting ready to buy a capri 1750 with the same motor and I'm looking for any little advantage I can get.

[@CDavid1951]

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. 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. Dave C

[@albertrodriguez6539]

99 Pro-line 3400 cuddy cabin , twin 07 300 HP verados . What will be my best props set up ? Three or four blades ?

[@BornAgainBoating]

Probably the 4 blades since your running a heavy 34 foot cuddy boat. You could use the extra grip. Unless you want top end speed though, if you want the speed go with the 3's but if you just want cruising and control, the 4's will handle better.

[@albertrodriguez6539]

@@BornAgainBoating Thanks Bud . I am presently trying a three Blades Mirage Plus 21Pitch . Any recommendation on a Four Blade , pitch and make ?

[@pedrobrizuela4615]

I have a 23.4 sailfish with a 200hp ox66 and prop with a 14-1/4 x17m I’m only getting tops 46 rpm’s It that a prop issue or motor issue

[@motorv8N]

Thanks for the info. Any thoughts on aluminum vs stainless with respect to performance? Ive heard aluminum can flex a tiny bit and lose some grip vs stainless which is way more rigid (but way more dollars too).

[@BornAgainBoating]

Exactly what you said ;) the aluminum will flex and are nice if you hit something, but the stainless are solid and give you a better bite on the water, but, at a cost lol

[@motorv8N]

Thanks for the reply! Yes, I use aluminum because my inland boating is on some beautiful but brutal lakes for underwater, unmarked rock shoals. Rather shred a prop than my driveline. 😬. Can't beat the bling of stainless tho! 😎

[@reddawng43x91]

Aluminum ain’t Flexin on any small hp motor such as his 25

[@MikeSsuncoasttrains]

I have a 1973 searay srv220 with a Ford 302 v8. Big heavy 24 ft boat. It came with a stainless 17 prop. Great out of the hole but can only get to 27mph or so. So I went to an aluminum 21 pitch . Will do 30 mph at lower rpm. I'm told a 4 blade would not help. That true?

[@BornAgainBoating]

A four blade has one more blade, generally it will take away speed if you get the same prop without changing the pitch or anything else

[@MikeSsuncoasttrains]

@@BornAgainBoating thankyou for the reply. I'm gonna try a 21 stainless.

[@craigbielsky115]

@@MikeSsuncoasttrains your logic makes no sense and your math is wrong you give no rpm values and im sure 100% 21p is way to much for a 24' boat with a ,little 302 .....16x16 4 blade is the ticket im sure your lugging that motor with a 21...

[@AnthonyCavalieri]

Could the motor not being run at the recommended range wear out the impeller faster?

[@saliaccarino7140]

Great video. I had to get the height of the engine right before I changes out props. My engine was too low. #cleanboat

[@newshortplay9212]

How long does the engine work if the engine does not get oxygen or air?

[@BornAgainBoating]

Not long, a few revolutions maybe :/

[@newshortplay9212]

@@BornAgainBoating i want to running engine underwater

[@newshortplay9212]

@@BornAgainBoating hi

[@newshortplay9212]

@@BornAgainBoating can you connect with me.

[@wuzgoanon9373]

Good info. I need to look into this on my own ride.

[@dillee9988]

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.

[@BornAgainBoating]

That I'm not sure about man, you'd be best to call a prop shop and ask them, or use the online calculator :)

[@craigbielsky115]

13" or 15" 4 blade

[@silvajay6443]

@dillie9988 did you figure it out.

[@timrainger8908]

Just went from a 3 blade to a 4 blade on my V4 115 2 stroke, is it normal to see up to a 300RPM loss at idle? Thanks!

[@BornAgainBoating]

Not really, the prop shouldn't have anything to do with the idle RPM of the engine in that much of a fashion, if it did, there might be something else going on

[@timrainger8908]

@@BornAgainBoating thanks for the response! You are correct about something else being the problem, boat sat for about 3 weeks after I installed the prop I think i got nailed by ethanol gas I was runnin, I usually only run it in the summer. I was getting the lean sneeze, took 2 boat days of non ethanol gas and 2 bottles of Seafoam marine but shes good to go now.

[@joshgtheog3371]

we have a 90hp jhonson with a 4 blade 14 pitch prop

[@randycooper2046]

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.

[@craigbielsky115]

LOL I CANT BELIEVE HE SAID THAT...LOL LOST ALOT OF CREDIBILITY THERE

[@emmanuelmeyermeyer1083]

We all make mistakes. Give the guy credit for his other info and trying to help people out.

[@randycooper2046]

@@emmanuelmeyermeyer1083 this wasn't a mistake, this is a basic misunderstanding of how it works. I applaud anyone for putting information to help others just make sure you know what you are talking about. And when you don't know, don't comment or say you're not sure.

[@hellion1770]

I run 3 props 1 for speed 1 for water skiing 1 for heavy load No one prop will do it all.