Suzuki DF150 propeller

[jayw]

Hi all, I might open the proverbial can of worms here... but hope someone has experience (or at least some interesting opinions).

This is our first yr with our 2nd pontoon - a big upgrade from our 2 cyl Merc 2 stroke. It's a JC Neptoon 21tt triple toon with a Suzuki DF150 4 stroke. I am not convinced I have the best prop setup. When the boat was delivered it had a 19P stock aluminum prop. That was underpropped as the motor was running into the rev limiter at WOT (this was after I followed the break-in period instrs to the letter). So our dealer swapped it out with a 3 blade 14.25x21 aluminum. This brought our WOT under normal load (which is me and my wife and about 150 lbs of gear plus 15 gals fuel) to exactly 6000, trimmed down. That translates to right about 34/35 MPH (by GPS).

I'm thinking about going to a stainless. Maybe 14.25 (give or take .25") x21, or step down to a 19P and go 4 blade. I want increased performance and fuel economy.

Anyone have any experience they could share?

The fuel economy has been decent but I do think it could be a tad better. And I think that motor should get me a few more MPH. I'm basing that on a Suzuki test I saw with a Landau triple toon and the same motor, and general experience around boats.

[dockholiday]

check this one out. i know is is a merc prop, but you can get the hub for it. i am running a 15x15. thinking either a 15 or 16p would work for you.
http://www.mercurymarine.com/propellers/comp/enertia/
they were more or less designed for center consoles but do real well on toons. think there is more stuff on you tube.
doc

[jayw]

Thanks dockholiday, I will look at the Enertia. I've seen people running them. I know they're expensive. Truthfully with the shallow lakes we operate on, I wonder if an aluminum 4 blade isn't a good place to be. I have a 14.25x21 3 blade, thinking 14x21 4 blade. I've been told to go up to a 15x21, but wow that's a big prop.

I've talked to 3 or 4 prop pros and they all have differing opinions about the prop. Except one thing seems to be constant - they've all suggested I consider 4 blade.

I want smooth operation across the whole throttle, best possible top end and fuel economy. Then again, who doesn't.

Is that reasonable expectation from a 4 blade, either in SS or ALUM? I've never owned a 4 blade prop. Come to think oof it I've never had a SS prop. Our Suzuki dealer I think is just content with getting the prop in the right RPM range, up near 6K. I don't think he wants to be in the prop-chase game for every motor he sells. I can't blame him. I'm willing to go down that road on my own - within reason.

Just wish I could find someone with a DF150 or DF175 on a Neptoon 21TT or 23TT who's gone thru this. I know one guy, he's got 23TT and DF175 and claims to get a few MPH over me, but I drove his boat and (with algaed toons) it wouldn't break 30. Our boat is not left in the water so no algae concerns.

[dockholiday]

yep the enertia isn't cheap. don't think you are going to get what you want from a four blade. I have never ran one, but from what I have heard it is like having a 411 rear end in a car. great coming off the line but not so much on the top end. really need to find a prop shop that will work with you so you can try a wide variety of props. The props today are much better designed for best of both worlds today than years ago. but still lean a little to either hole shot or top end. Thinking 38 should be doable with your boat, although not sure of the weight. For a 24 mine is pretty light. I am right at 40 with the enertia an got 38 with a 17p mirage plus at 5300 rpm max. Going to the enertia put it right where the rpm needed to be an picked up the 2 mph. There is a shop in Fla called Prop Gods, heard they are pretty good in helping with selection, seems like there is a fee involved and I have never used them.
doc

[jayw]

boat & motor about 2500#, plus fuel (takes 55 gals but we run with 20 or 25 max), me & my wife, and 125# of gear brings us over 3000#. That's double the last pontoon. But it's worth it.

I've eliminated all the tempting "value" SS props. Solas, Stiletto, Mich Wheel, etc. And I considered the Enertia. But I'm really leaning toward the PowerTech. Very high quality props. About the same money as the Enertia.
http://www.ptprop.com/component/page,sh ... Itemid,46/

4 blades or 3, that is the question. It seems among the pros in the know that it's the blade surface that's killing me. More have recommended 4 blade than I might have thought. FYI Saw Prop Gods online and I think they said they limited help to FLA customers(?)

I talked to tech support @ Power Tech and they rec. 15.25" diam for the DF150 and 175. I'm at 14.25 with the cheapo AL prop from the dealer. That's why over 5000+ RPM range the motor spins faster but we gain littte add'l speed. And at ~5600RPM we gain no more speed. He did some calculations for us and determined we could be as high as 30% slip. That would explain a lot, like why our fuel economy isn't wherre it should be. Theories:

1) we aren't getting quite enough clean water. I have 1 more hole to go down on the motor but I want to do the prop first (see #2)
2) there simply isn't enough blade surface. This engine is geared 2.5:1 which is low, and needs more balde surface. Hence the 4 blade and 15.25x18 rec. from the 14.25x21 3 blade AL. They gave me a 3 blade option and said it will be faster top end, but the range of performance will not be as good.

Conventional wisdom says I will lose top end. But based on where I am now, with all the slip I have, they're thinking I will gain top end. And also:
*better fuel economy in the mid range and cruising speeds, up to 25% though I am not banking on that.
*smoother ride (though the Neptoon is pretty smooth)
*better handling at no-wake speeds (docking right now with that tiny prop isn't great)

the 15.25x19 3 blade they recommend will give higher top end but that will fall off faster under greater load. Truthfully I just want the prop that will give me the most out of that engine. Top speed is very imp, but not the only consideration. I'll think it over a bit and be sure to let everyone know.

And they have an exchange pgm, $50 + shipping to exchange the prop if it isn't right for the boat.

[greezzmunkei]

I've got a tri-toon, and a zuki DF140 and was having the same problem. With a ton of trips and observation time we were able to completly correct the problem.

The center toon was pushing the water down so hard under full throttle that we were losing water to to the prop. A slight turn would result in immediate cavitation and instant redline shut down. Under full throttle in a straight line with a 13.75"X15" prop, I witnessed the water pump intakes out of the water that was causing an overheating alarm and shut down.

Soulution: 9" static jack plate with 14"X19" prop. & whale tail.

The water still gets pushed down but now has time to come back up to the prop. Turning is awesome, no more blow outs or overheating. The extra leverage allows me to plane much easier (I have strakes also) with more people on board. Higher top end results also.

The latest tests with this setup allowed 29 MPH with 12 people (7 adults 5 kids) and one on the tube (teenager).

Great results.

PS. a 15 inch diameter prop WILL NOT FIT on the 115 and 140 DF series engines (it hits the cavitation plate) so be carefull with the 150 and take measurements before commiting cash.

[dockholiday]

Saw a video on youtube with the power tech guy and he seem to know what he was talking about. One thing the enertia claims you can run a little higher pitch because of the composition (alloy x7) it is made of. A jack plate with a set back would really help and with your boat,the cost could be justified. Might be able to pm bryden on here. He knows a lot about the jackplates and props also pros an cons of electric over hydraulic plates. I had considered one for my boat but have not followed through yet.
doc

[jayw]

Hey that's great info, thanks. 29MPH with the 140 under that that load is impressive. I don't know about the jack plate though, I think I'd have to find that I'm completely dissatisfied with prop change results before I went down that road... my wife's already about to sh#t. She wanted to spend half what we spent. Plus I still have 1 hole to drop on the pod. If I need it. It's about getting more prop in the water.

The DF150 will take up to 16" diam prop. It's designed to spin the larger prop.

I've been on the phone and the internet for days with this. And I've had a reverse of thought. I am probably gonna try a 15.25x19 3 blade SS Merc Quicksilver Thunderbolt (Mirage w/o the ventcaps) or the Power Tech OFS with same dims. Both offer a huge increase in blade surface and strength over what I have now. And design. Advantage for Power Tech is I can exchange to 4 blade if I decide 3 isn't right. If 3 is wrong, I go to 4. Disadvantages of 4:

*the add'l stern lift of the 4 blade. That may just push me higher out of the water.
*more drag over a 3 blade prop

I expect better economy (way less slip) and top end either way. And I hope I don't pick up any noise. Or bow lift.

Oh yeah and Prop Gods helped me a lot on the phone, I may buy from them. They have good prices and seem responsive.

[jayw]

I beat this to death long enough. Today I ordered the 3x15.25x19 Power Tech OFS prop from Prop Gods in Florida. We'll see how it goes in about a week. If I don't like it I'll change pitch or go to 4 blade.

[dockholiday]

hope it works an you can get the rpms. most i remember reading from the fla bunch seemed like they are well versed so i am sure they would not recommend a prop that wasn't right like some dealers put on the new ones. It amazes me when people say that is the prop that came on there when it was new and it has been on there for over `10 years. I don't fault the owners or buyers but the dealers for not at least saying in my opinion this is the best prop, however if you don't want to spend the money I can put this whatever on cheaper.
doc

[jayw]

OK so back with a report on the Power Tech prop...

But before I do let me speak in my dealer's defense a bit. He's really a stand-up guy and has bent over backwards for us. He did offer his opinion on the SS prop. We discussed it as an upgrade. But frankly we wanted to start with the AL prop and see how it did. Wasn't quite there for me, even though I see lots of pontoons with bigger motors and AL props up on hoists around the lakes. Anyway, once we did get to taking about SS options I realized he didn't have the mfr lines I wabted to consider, and couldn't compete in the price category on what he did have. He suggested I look online. The only thing left for me to do was to do some legwork and find it myself.

So, now back to the real reason I'm typing.

The prop has made a huge difference in every aspect. I have an impressive holeshot that will damn near pin you to your seat, and gets me to 30+ MPH lightning fast. Top speed with fairly calm winds and waters and 1/2 tank gas is ~37. And the fuel economy has improved, though I cannot back that up with concrete stats/figures as I don't have a fuel computer to prove it. But, I can est. how much gas I'm using per hr of operation and I am convinced it's down considerably. And the performance over 5000RPM is hugely improved. I can still give it some juice @ 5400RPM and feel it respond nicely. @5000RPM I'm running about 32 MPH, me & the wife.

Today, with over 1/2 tank gas and 550 lbs of people on board I only got to about 5750/5800 RPMs. But with me and my wife, which is the typical passenger load, It's more like about 5900. I'm not stepping down to an 18P. I think the prop is dialed in optimally given our use. We rarely run WOT, the top end of our typical cruise range is about 5200RPM. But by all accounts we gained 2-3 MPH top end and better performance and economy across the entire power band.

Just what I was hoping for. Overall it's an awesome choice of prop for this boat and I would recommend it to anyone.

Now we don't have, nor will we ever have, the fastest pontoon on the lake - or even close to it. We're definitely in the upper quarter, at least, I'd say on our lakes but there are plenty of tritoons with 225s that are faster. Our goal is not to be the fastest. But it's fun to turn heads in our beautiful pontoon when we zip by @ 35 kicking up a mini rooster tail. Fast power boats are everywhere. But people are always watching us go by, and complimenting our boat at the docks and in the channels.

Again for posterity sake & in case anyone is ever interested, the prop is the Power Tech OFS3R19CLS200.

[dockholiday]

That's great. Liked the way you explained the performance. Good lesson here also. You can't always go by the pitch number although it is helpful in getting in the ball park. For example I could only turn 5300 max with the 17p mirage I first tried. It did get the boat up on the strakes much faster than the 15 enertia though. Plus I lost that high rooster tail from the 17p that made it appear I was going 5 mph faster than I was going. I did bump the rpm to 5900 an picked up one and half to two mph going to the 15 enertia.

Glad you got the results you were looking for. I agree as long as you are in the 5800 range it's sure not worth considering a change. Glad the fla bunch could help you, and sure the results will more than justify the effort an cash to make the change.
Most will not be happy with their boats performance, but keep the same prop installed by the dealer till they trade it in or sell it.
Congrats in hanging in there and getting what the boat is capable of delivering.
doc

[Bmac]

Didn't see this post till now. I'd be willing to bet Power Tech will recommend the OFX3 or the OFX4 for any of the big DFsuzuki's. I tested quite a few of their props on large group of heavy bayboats back in '02-'04,back when they first came out with the OFX. Was even a dealer then. I remember one boat with a big DF that we tried a 1/2 dozen known fast props on. Kept getting screwy data back until we tried an OFX4. Made a new boat out of it,and it was the fastest up to that point. Best we could figure is those big DF lower units punch a large hole through the water,and require a large dia. prop.

Personally I'd have to say the OFX4 was the best driving prop I've tried. Still have that prop on a shelf. Decent rake and tip cup carry the bow well,yet those long trailing edges lift the stern. Less blade surface and more cup than most big blades let it spool up fast and bite hard. Carried the whole boat higher out of the water. Worked great in rough water or carrying a heavy loaded boat. Used that prop a lot when I guided and fished tourneys. Wasn't a real fast prop on my boat running light,but probably the fastest loaded heavy and the most efficient. Also a good skinny water prop,as it would bite half way out of the water. Never tried it on a toon. Thanks for the report.

That blade has probably made PT more $$ than any other profile. As much as I wanted their props to test faster,the yammy and merc props usually took them on topend. There's more to a prop than topend though. I will say that their 15 1/4" VMX 3 blade was the fastest 0-60 prop I ever ran,under 13 seconds on a 3500 lb. boat.

[Bmac]

Ha, still have pics of Rob's DFsuzuki/OFX4.





Hard to make out,but I also found an old graph we use to fill out when testing props. Used the numbers from rpm,mph,and jackplate settings.

[Shopguy]

I've always been a huge fan of the mirage and the PowerTech OFS props cause their BIG. I borrowed a Mirage when we got our 24 ft Caravelle and loved it. When it came time to get my own prop I'd decided to go with the ele 4bld series powertech prop and liked it even more (wish i'd went with the OFS). We did more tubing and cruzing than anything. This boat would run around 62 and I don't. I'm more of a 45 kinda guy on the water with family. I found the benefits from a larger prop to be supreme at towing and cruzing over a measely couple mph on the top end.
Granted spinning a 4th blade does take horse power and increases drag but it's minimal and most of that loss is at the top end, and at higher speeds then most pontoons will go. I doubt by going to a 4 blade you'd notice much difference in top end until you get upwards of 50mph.
GO BIG 3 or 4