Michigan/Piranha/Solas Props on Suzuki DF50, 26M

[Frank C]

... I would be happy if I could go 14 knots loaded, as running on the ocean empty isn't for me. ...

Mark,
You're comparing your DF50 to the ETECs, open ocean, and you're running with full ballast.
But are they running ballasted?

FWIW, I always empty the ballast when using the motor at speed - on the Bay and also crossing the Santa Barbara channel. Granted, this is generally only for milder conditions, and with no more than 2 or 3 adults aboard. Any larger crew, or some kids, and I'd be using ballast too. It's a very personal choice, but you may want to test the concept in the Harbor.

I didn't realize the 26M with the lighter outboards (i.e. 12" props) had this bow-heavy attitude.
Sounds ripe for a mod. How 'bout this one:

• - Enlarge the ballast vent hole to 2-inch diameter;
  - Stuff a net-laundry bag thru same, down into the ballast tank, net-mouth up;
  - Plop 2 dozen ping-pong balls thru same hole (into the net) & cinch it;
  - Add balls judiciously - a dozen more at a time;
  - ( since they're easier inserted than removed! )

There's now a good-sized bubble to help the 12-inch 50s with hull balance!

[Sailfish]

Mark this is a good point I always have a full balast tank, But by summer I will try it empty for fuel savings and speed approx (2-3 MPH by your test) good sailing Phil

[aya16]

The bow down att. of the M is not a bad thing. when running at speed through the ocean I find the boat does not slam at all. Also by placing a 90 on the back doesnt seem to effect the bow down att. as seen on scotts boat with a tohatsu whatever you call it. As mentioned before when the boat is at the dock with no one on board the boat sits bow down but as you add people and gear to the aft it almost evens out.

But if the boat is brought to a bow up att. I can see where slamming will happen at speed.


Mark there is still some hope: we didnt test my prop (we should have but it was so far off the rpm range we didnt think it would be worth it) buttttttttt my 11 1/2 by 13 inch prop will without ballast will run at 16-17 mile per. so maybe we are barking up the wrong tree with the mich. wheel props. we are thinking that the larger diam. prop is best. But maybe we dont have the gear ratio to support this. Next week Im taking my boat out
and get a good reading mph and rpm with my prop. if my prop does 5000
wide open at 17 mph then a suzuki 11 inch might be what we need. the suzuki has an 11 1/2 diam 1/2 smaller then the mich. having the blow out I did make me think the 12 inch is too high and breaks the water more than my stock suz. prop. I do not cavatate as much with the suz. prop or the pir. even though the pir was larger in diam. I think the blade flex more so we didnt have the blow out problem

so we need a suzuki prop to try 11 pitch when Moe tried the mich wheel prop he had the same problem of blow out as I did.

I think more pitch less diam might be the answer. If your comming to MDR
on sunday then Ill be there about 11am I dont have a lot of time to test things but you can take my prop and try it.


I still dont think we will get the performance like the etech's because their boats are loaded much lighter and with a large diam. prop and 13 inch pitch deeper in the water they are going to be a couple miles an hour faster. as they add weight to the boat the torque of the two stroke wont be able to match the torque of the four stroke and they will slow down a lot.
but this isnt about what engine is better its about getting the ideal performance from the Mac. The Mac needs unballasted about 15-17miles
per hour to be on plane and has more control. mine does that with my prop. once the boat is on plane (if we had the horse power) we should be able to back off on the throttle a little and maintain that speed. But we cant. My engine is full throttle at those speeds and I cant back off.With a 90 the engine doesnt even break a sweat at those speeds even with the
ballast full.

conclusion: lets throw out the thinking that a larger diam. prop is the answer and think about smaller with more pitch to get the rpm 's right.
If my 13 does 5000rpm then a 11 should get me into 55-5800 range.
but I wont know till I try it next week. hope fully Im in the 5500 already and the 11 will be around 6000 ballasted.

BWY recomends a 10 but Ill bet its a suzuki 10 not a mich. wheel.
the price they are asking is about what the suzuki costs. If you take your prop back to anderson and ask for a suzuki 11 Ill bet you have close to what you want.

I know its frustrating but look at it this way when were done we can be the experts on prop selection for the df 50.
Plus the etech guys can have some fun with us till we switch over.
Im ok with that. Right Phil?


by the way did the anchor fit the bow locker?

[Catigale]

I think this is a performance and tuning thread - do you guys agree?? I will move after you get all your data and discussion done...

[Mark Karagianis]

I talked to the tech guy at Pirahna to ask why the blades for their 11-pitch were shaped so different (smaller area) from their 9-pitch. He develops the props using complicated software and said there are lots of variables; the 9-pitch (and an upcoming 8-pitch) was developed for pontoon boats. I begged him to develop a 10-pitch with the big blade, but he said they were snowed under with other development projects for 2 years. I told the Piranha people about this Board and my testing, and I'm hoping that if they read this maybe they will adjust their priorities.

Yeah Mike, what we need now is to do a Suzuki 3 x 11.5 x 10 or 11-pitch comparison with my new 3 x 12 x 11-pitch Piranha and that 3 x 12 x 10-pitch Michigan (the dealer thinks they still have it - dibs). We'll use my boat with full tanks (oouch, but I might as well fill up now for Catalina while I can still get gas at $3.35/gal!) and that way you won't have to empty your gear. Anyone want to meet at MDR & bring your prop?

And to add still more confusion, Suzuki makes a 3 x 11.75 x 12 in stainless.

Frank your ping-pong idea is brilliant, but I don't seem to have the bow-down problem, I guess because I don't keep anything heavy in the bow. I'm trying to think of the boat like an airplane, where everything that's heavy needs to be left behind unless it can be justified. I'm fretting over the additional weight of my new anchor, and Mike I haven't tried to see if it fits yet, thanks.

Mike, I'll call you when Diane tells me my weekend Honey-do list!

[aya16]

hate to say this but if the pir blades are not as big as the 9 then I think the bite will be a lot less and the rpm will be through the roof. so a 13 or
bigger might be the one for the pir. If you go sunday what time would you be there?
If you go out early Ill change my plans a little and go out with my boat
also. we can test your props on your boat useing my prop on my boat as a bench mark. There is a guy from the other forum that wants to go for a ride and kill two birds with one stone. My only problem is Im bringing my motor home and have no Idea if it will pull my boat out of the water. If your there then I could get help from you if its a problem.

depending on the rpm range of my prop, I will buy the suz. 10 or 11 and
use that later. If my heavy loaded boat goes faster than your lightly loaded boat with the prop i have now, then we can go back in and you can pull my prop put it on your boat and you can go back out if you want. but if you could wait to see if I can get my boat out of the water.

I know that this should probably be a pm but others might be interested
in the progress and plans. If any etech guys want to go out and blow our doors off your more than welcome.
Mike

[Bobby T.-26X #4767]

And to add still more confusion, Suzuki makes a 3 x 11.75 x 12 in stainless.

that's too much pitch for a Mac.

a suzi 50 - 12 pitch prop with two adults and gear won't get you to 5400 RPM's at WOT.
i know that for my '02 suzi i had a 3 x 12.25" x 10 pitch Michigan that had plenty of surface area. it got the RPM's up to 6400. however, i used my Michigan 3 x 12" x 11 pitch (which looked the same as the 10 pitch with large dog ears ) most of the time. the 11 pitch normally got me to 6100 and gave me more speed.

however, M's are generally heavier than X's.

Suzuki 50 Michigan Prop

Bob T.
"DaBob"
'02X w/ '04 90-TLDI

[aya16]

The problem we seem to be running into is not all props are equal.
the pitch on one prop and diam. are diff. from another maker. the pitch
and diam might be the same but the ears are a diff. shape.
seems we have to try all kinds of stuff. with an open mind. Right now Im leaning toward the suz. props because of the performance I get from
a 13 pitch smaller diam. prop compared to all the others we tested.
even though I dont think Im getting the rpm's I should it seems to perform better than the others we tried. The exact same prop with a two inch less pitch might get me a 1000 rpm diff. It shouldnt it should only give me about 400 rpm diff. but if it planes better than I might get the 1000 rpm.

all the props we tested there wasnt a big diff in any of them except the pir.
it reved up to almost 7000 rpm but the speed was down. Our thinking was because it was a 9 inch pitch, going up to a ten or 11 would put the rpm's and speed in the ball park. Butttttttt the new ears on the pir. are smaller than the 9 so its going to make a diff. I think. The stainless 12 might be the ticket if the rpm's can get into the 6000 ramge. but for now its all guess work till we get some more props to test. we will test mine then a
10-11 suz. pitch prop and see.
I still think there is no sub. for horse power and right now we are on the
edge of what we need. The right prop could put us a little over and thats what were trying to do. The larger diam. props seem to ride to high to get a clean bite on my boat. so Im looking at a smaller diam. with more pitch.
Then do we want cupped or non cupped? The suz. props are not cupped.
the mich. wheels are I think. And if they are they are not working well for me. so all the standard thinking about useing the cupped large diam. less pitch isnt doing it. so Im trying to think outside the box on this one.
and this only effects the suz. df 50 other outboards are a totaly diff. story.
my next big step would be to take the engine off Marks boat install it next to mine and run two DF50's at the same time and then we have something....

[Robert]

I tested 9 props on the Suzuki DF50 on my Mac26X. The best pitch for the Suzuki prop is 10 pitch overall. You get to the top of the WOT RPM range with ballast empty and maybe 6200 RPM with ballast full.
..
I prefered the Stainless Solas 3x12.25x9 with a slight extra cupping for best overall prop. It reached WOT 6800/6400 Ballast Empty/Full.
..
I prefered the Aluminum Solas 4x11.8x9 with for best overall prop right out of the box. It reached WOT 6800/6350 Ballast Empty/Full.
..
The Solas 4 blade 10 pitch 11.4 diameter is also a good one.
..
Note that the torque of the DF50 falls off at 6800 RPM, this is where many props will top out with ballast empty. I suggest that you get a prop that will hit 6800 RPM with ballast empty and shoot for the top half of the RPM range with ballast full. Boats only get heavier over time as stuff gets added on including marine growth and beer and anchors and spouses and children with tow toys etc... The general rule of thumb is ask your outboard machanic what prop is recommended for pushing a 4000Lb. pontoon boat and you'll be about right. If all else fails get the lowest pitch prop available with the largest diameter and most prop area, It is doubtfull that you will exceed 6800 RPMs where the torque falls off and there is an over-rev limiter at 7200 RPM. If your prop sucks air from the surface get the prop cupped slightly or lower the motor a little.

[aya16]

Robert what speed are you reaching with those combos?
all the props we tested we could get all over the rpm range but speed wasnt there. My 13 seems to be faster but way less RPM. (go figure)
My engine is down all the way and there might be some extra weight I could bring aft to help with the blow out. ole lord I need a 10 inch 4 blade prop 12.5 inch in diam big ears???? orrrrr an e -tech 90 white of course.

[Bobby T.-26X #4767]

Robert what speed are you reaching with those combos?
all the props we tested we could get all over the rpm range but speed wasnt there. My 13 seems to be faster but way less RPM. (go figure)
My engine is down all the way and there might be some extra weight I could bring aft to help with the blow out. ole lord I need a 10 inch 4 blade prop 12.5 inch in diam big ears???? orrrrr an e -tech 90 white of course.

top speed for me on my '02 X - '02 Suzuki 50 with the 11 pitch Michigan (12" diameter) was 18-19mph ballast empty lightly loaded, just me at the helm. 6100 RPM's.
again, this prop had more surface area than the stock 13 pitch that came with the motor.

IMHO, don't use the 13 pitch that you're currently sold on for speed. with any kind of weight in your M you'll damage the motor over time due to RPM's at the very low end range.

however, if you are planning on going out by yourself with absolutely nothing in your M (no anchor, only 1 battery, 2 gallons of gas...u know what i'm saying), then the 13 pitch might be OK and you'll get to 21mph.

otherwise 11 or 10 pitch...or white etec 90.

Bob T.
"DaBob"
'02X w/ '04 90-TLDI

[Moe]

My initial problem with the Michigan Wheel 9" four-blade Vortex prop was exhaust gas leaking out ahead of the prop causing it to ventilate. MW copied the Mercury interchangeable hub system, but poorly designed the front thrust washer for the Suzuki DF40/50. There was almost no overlap between the leading edge of the prop hub and gear case.

MW redesigned the thrust washer to allow the prop to sit slightly deeper in the gearacase.. They sent me the new one. I wasn't really happy with it, since the prop still sat out much further than the stock Suzuki set up, but the MW engineer said it would be enough. One thing to watch for is that they used the exact same part number on the new thrust washer as the old one.

I never did get to test the new setup before I sold the boat, but Don tells me it works fine and he got 20 mph at 6,800 rpm with the boat unballasted, lightly loaded, mast and boom left home. So I guess the MW engineer was right.

If you're having ventilation problems with a MW Vortex prop, check my measurements and see what thrust washer you have.

[Frank C]

I have also been searching for the right prop for my Honda 50 on a 2005M. The problem I am having is Ventelation, air being drawn down from the surface, when i am in turns with ballast empty or just motoring in small chop with ballast full. The transom design puts the motor so close to the surface and when you have ballast in the bow is down more than the stern. I know most people I have talked to with M's are having the same problem. I am wondering if a smaller diameter is better, possibly the 4 blade like Terry runs. Anyone else solved this problem.

The bow down att. of the M is not a bad thing. when running at speed through the ocean I find the boat does not slam at all. Also by placing a 90 on the back doesnt seem to effect the bow down att. as seen on scotts boat with a tohatsu whatever you call it. As mentioned before when the boat is at the dock with no one on board the boat sits bow down but as you add people and gear to the aft it almost evens out.

But if the boat is brought to a bow up att. I can see where slamming will happen at speed. ..

Sounds like a design improvement on the 26M - but a 2-edged sword. The factory was trying to improve on the 26X, and maybe you're just fighting the design compromises.

A criticism of the 26X, regardless of motor weight, is that it never quite manages to climb over its bow wave. This gives it a radically bow-up attitude when planing. (Many might say, "... it's just trying to plane.") It's rumored that they slightly repositioned the 26X ballast tank in '99 because of bow-attitude and because of the trend to heavier outboards. First words of wisdom from my Mac dealer were: "Use your ballast if you want a stable, but very wet, Bay crossing ... ballast empty for a quicker and a drier ride!"

Seems to me that the M-owners have a big advantage, both for planing and for beating under sail (mitigating wx-helm). But, perhaps Macgregor's attempted correction, if any, has a gotcha ... sounds as if the lighter-weight motors carry the prop too shallow? As Mike observes, that's still not a bad thing. It provides lots of spare, "crew" buoyancy. It also means you never need worry about a full load of fuel, ice, beer ... or all four.

I'm not a pilot, but one can see by reading that load-balancing is no mystery to the pilots in the group. M-owners might recognize your advantages, concentrate on your waterlines, and load your boats accordingly. (& don't forget that if your motor is only 200#, there might be another 200# of reserve buoyancy back there.)
Next 26M mod, starb'rd aft berth sliding track with twin 70qt. coolers!

[Robert]

aya16, The top boat speeds I experiences were 20 to 21 mph. With the mast left at home and just enough stuff aboard for messing about in one afternoon. Plus some of my family including the mother-in-law. My mother-in-law is cool!
..
The fastest prop I ever used was the Piranha 12X11, once it was near top RPM range 6800+ on my Suzuki DF50 it performed wonderfully. However, at RPMs below 3000 the Piranha 12X11 had hardly any thrust. I never even bothered to test this prop with ballast full. I think I recommended the Piranha 12X11 to some people who had the 1.8:1 gears and therefore higher prop RPMs, but I don't know if they tested it.
..
The other props that worked really well: Suzuki 10 pitch, Solas 3x12.25x9 stainless, and the 9 and 10 pitch Solas 4 bladed props all achieved about the same top RPMs, close enough that slight differences in weather conditions would blur the comparison. They all were in the 19 to 20 mph range without ballast and without the mast. With full ballast and the mast and weekend stuff for four people the biggest surface area prop with the least exhaust restriction was tops by maybe 1 mph, this was the Solas Stainless prop, but it needed slight cupping to not catch air with my Suzuki mounted cavitation plate just barely below transom.
..
So, the pitch alone does not determine top speed. The Mac26 does not go fast enough for prop drag to matter at all. So get the big low pitch prop, it will be the best performer.

[Tahoe Jack]

Hey Moe.....excellent analysis re the Michigan Vortex....bought the same 12x9RH 4 blade...'992402', with the recommended XHS 115 hub system (Suzuki), and had the same dismal performance. Only ran it one day and stowed it as a spare. Measured the washer today and found 0.81" meaning I have an early one. Will contact Michigan for the replacement.
Thanks for your research. Any recommended direct contact phone or email for Michigan?
My original prop is a 3 blade 12" at about 10 pitch (Suzuki?). At Tahoe elevation (6200') we surely develop reduced power. Sunday I got 12mph heavily loaded w/o ballast, and max RPM of 5400. Will check linkage to verify we are full open on throttle. Also expect to put in at lower elevations soon so ....is this fun or what? Plan to watch this thread for the best sea level setup. Tahoe Jack