New 2010 Suzuki DF90A + 26X = BIG Success!

[Stefan]

Well,Victor, I have some news.
I received my Rubex prop yesterday with a RBX125 hub kit. Unfortunately I already ordered it before you warned me about the hub problem.
I tried it on today, sure enough the HUB would not fit due to the thrust washer, the one with the hub is completely wrong, but the original from the engine is too thick. I started calling every dealer that sells Solas props, but everyone was assuring me that rbx125 should fit, that there were no changes from DF90 and that I was doing something wrong.
Strangely enough the Solas web-site does not have the contact number for the tech support, just the email form that I didn't want to deal with. Finally I Googled out the Solas guy in Florida and he immediately told me that there is no Rubex hub for the newer DF70-80-90ATL line yet, and wouldn't be probably for another 3 months. It would be called RBX150.
He confirmed what I figured out, that only the washer needs to be trimmed about 5mm of it's thickness, that's what they are doing right now. No other changes to the 125 hub. That's kind of good news for me, since I don't want to wait that long, I am thinking of ordering additional OEM washer, I believe it has the catalog number: 57632-87L00 STOPPER,PROPELL and take it to some factory with dedicated tools to slice those 5mm off. Just don't want to mess with my original washer since I want to be able to use my current prop.
So, there is mo time to wait for the test.

p.s: just checked some sites and see the price for that washer is between $50-$70

[vkmaynard]

That's too bad. I sent you an email with the Solas contact information today after I received you replies.

I think there is more than triming required on the washer. It looks like a totally different interface to the back of the prop.

Marc at Solas recommend the larger diameter prop for our Suzuki motors. The stainless props are all smaller than 13.75. If you don't want to wait try the 13.75x15, get some numbers, and determine if you need to take out 2" of pitch. 1" pitch decrease changed the RPM by +350 in my case.

Keep us posted.

Victor

[delevi]

Victor,

I'm quite impressed with your new engine. Congratulations! If I have no luck with the BRP rep in May, I may just repower with a Suzi 90. I would hope the performance results would be similar on an and that it wouldn't hit the seat when fully titled up. What's the deal with the warranty? Is it 6 years. Do you need to buy during a certain part of the year to get the 6 year vs. 3 year? Also, why did you find the need for transom plates? Just peace of mind of added support or do you think it's really necessary?

happy boating
Leon

[vkmaynard]

Victor,

...I may just repower with a Suzi 90. I would hope the performance results would be similar on an and that it wouldn't hit the seat when fully titled up. What's the deal with the warranty? Is it 6 years. Do you need to buy during a certain part of the year to get the 6 year vs. 3 year? Also, why did you find the need for transom plates? Just peace of mind of added support or do you think it's really necessary?

happy boating
Leon

Stefan can tell you how the DF90A fits on his M in Russia.

The 6 year warranty deal was offered until Mar 26th this year. Last year when sales where slow they reoffered it for the month of May. I would push on any dealer to include it now. For +$600 it is still worth the money. My 2004 Mustang GT just had $2,100 worth of service for electrical and mechanical problems. I used the Ford extended warranty I purchased online for $950 from a dealer in Texas. This is the second time I used this warranty with a third trip scheduled before expiration (steering pump noise).

The plates are peace of mind. I don't think you need them based on what I've seen on other boats. Billy added the plates to his Suzuki 140 26X and has had no problems. Bill (the ETec 90 Blue 26M in the video) added the inside transom reinforcing bar on his boat (purchased from Overton's). So for 8 hours work it's not worth finding out later that I may have needed them.

Based on the "Drag Race" video I am guessing that the M will be somewhat slower due to the hull shape. However, keep in mind that we can actually run 24 MPH with full ballast, mast not raised and no cruising gear. We do keep two large batteries and all the sailing gear in the boat with 18 gal of fuel

If you have a place, a friend (may need some beer) and can borrow an engine hoist, do the job yourself. Then it will be done correctly and you will know your boat better.

Start off with the 13.75x15 Amita 4 prop and see what it does. You can remove up to 2” of pitch which potentially could be +700 RPM based on my experience.

I think ETec is a solid engine (just sounds like it’s somewhat temperamental with poor and unknowledgeable service in your case). The blue 26M ETec ran strong. What I did not understand is why the ETec 90 (with some load and no ballast) is down to 4800 RPM (should be near 5500 RPM) with a 14x11 3 blade prop.

Maybe it is in the prop setup. If you do the math at the prop the Suzuki DF90A at 6300 RPM with a 2.59 double reduction is about the same RPM (within 300 RPM) as the ETec 90 at 5500 RPM with a 2.00 single reduction. I am a firm believer in using a 4 bladed prop on our boats. These boats are more like a barge than a speed boat.

Let me know if you have any questions.

Victor

[waternwaves]

at higher rpm,

a large dog eared 4 bladed prop is significantly more drag than a 3 blade...... on the order of 15-20% more drag........easily accounting for 300 to 400 rpm

[vkmaynard]

You also need to consider the weight and design of the boat and prop slippage.

You will have more drag at higher speeds (much higher than 31 MPH) with a 4 blade prop.

Our Honda 50 picked up 1-2 MPH with a 4 blade prop at the same RPMs as the 3 blade prop.

Jason at Blue Ridge Propellers and the riggers at Chtalee Marine also recommended the 4 blade prop for this boat (and others like the Carolina Skiff)since it is not a lightly loaded bass boat nor is it a speed boat. It would be interesting for someone else to try a 3 blade on this same setup. I can't imagine that it would be any faster (if not worse) at varying conditions. But since it's all magic there is only one way to find out. Trial and error.

I am looking forward to Stefan's report when he finally tests the 4 blade on his DF90A powered M. He has been running with a 3 blade todate.

Victor

[Bobby T.-26X #4767]

at higher rpm,

a large dog eared 4 bladed prop is significantly more drag than a 3 blade...... on the order of 15-20% more drag........easily accounting for 300 to 400 rpm

I'll say it again, it cannot be said enough...

"The boat is more like a barge than a speed boat".
Mac's have been referred to as a "Waterbago" many times on this site.
the goal is to prop your Mac so that it runs in the required RPM range.

that said, i believe a Mac should be propped like it's pushing a barge.
hence, the "pontoon" prop.
one that has very large "dog-ears" w/ a lot of surface area to push the water.



Bob T.
"DāBob"
'02X w/ '04 90-TLDI (14" x 11 pitch)
Dinghy Motor: '06 2.5-Suzuki

[bscott]

E-tec 90 max WOT range is 4,500/5,500 rpm so 4,800 is probably OK but 1 less pitch would be better.

Bob

[delevi]

Thanks Victor.

What I did not understand is why the ETec 90 (with some load and no ballast) is down to 4800 RPM (should be near 5500 RPM) with a 14x11 3 blade prop.

Now this is very strange. I'm currently running a 14x12 (3 blade) on my etec 50 and getting 5600 RPM (1 person, no ballast, fully rigged, bottom paint, 24 gal gas, 2 batteries, 6 gal water, fridge with beer, etc.) I know the gear ratio is a bit higher on the 90, but still. Arena yachts tested the Etec 90 on an with a 14x15 (3 blade) and hit 30 mph (one person, no ballast, mast up, 6 gal gas.) Something doesn't seem right.

Would be delighted to get the 28+ mph (25 kts) on any 90 and 20 kts cruise. Just don't want it to be an Etec.

Stefan, plese posts your results when you have a chance. I'm very curious to know if the engine clears the seat. BTW, where do you sail in Russia? I was born on the Black Sea coast (Ukraine,) but have been in the US since I was a child.

Leon

[Stefan]

Leon,
I have to disappoint you, this engine being rised does not clear the seat in the low position. I have to lift the seat in order to rise the engine all the way up, then I can lower the seat with no problem. That works for me.

I can not make any test runs with my new Rubex 4 blade prop yet, I need the new thrust washer, it looks like I could buy a new OEM one and try modify it myself, at least the Solas guy suggested that, otherwise I would need to wait at least 3 months until they come up with the new HUB, witch is RBX150.

Right now I have the Suzuki 14x13, 3 blade prop, if I remember correctly, I've seen max 5500 rpm with 2 people on board and empty ballast, the speed was about 22 knts (25mph). When I had 4 on board with full ballast I believe the speed was not more then 20knts, may be even less, I can remember right now, the RPM got to 5200. My goal is to bring it to manufacture suggested RPM, witch is 6300. I know the is a Hustler 14x11, 3 blade prop, but based on experience on this forum, I wanted to find a 4 blade prop.
Victor got some great tests done, but I could see that the HULL does matter, so I could not go his rout. Unfortunately every dealer told me that the RBX125 HUB would fit my motor, but only when it was already in the mail I saw a warning from Victor that he had problems with that. Now I have to deal with what I have, and hopefully I can work it out, just need to find a good deal on the stock washer. Here is the stock number I believe: 57632-87L00 , as soon as I get it and change it I will try the new prop. Hopefully the Solas rep. is correct that I could just slice off 5mm from it and it should do it for me.

regarding my location, I am on russian part of the Black Sea, you can see for yourself,
I followed this link and registered there:
http://www.macgregorsailors.com/forum/v ... ap#p162126

[beene]

I run with the Hustler 14x13 3 blade most of the time.

I also use the Hustler 14x11 3 blade for water skiing.

I can tell you the 14x11 is not needed to increase top speed, just hole shot.

Tempted to try Vic's prop just to see.....

G

[Trouts Dream]

on my Yamaha 90 HP 2 stroke I use the Piranah prop with 2 blade sizes, a 14 x 11 and a 14x 13, depending on load, elevation (sail at 3,900 ft here so use the 11 mostly), and what I want to do these two props pretty much cover it. Since it's not that big a deal to change from the boat, I will change if the top end is too high or too low.
Keep extra nut and cotter pins on hand anyway.

[Stefan]

well, after inspecting the RBX125 hub some more we decided to modify what we already have, instead of waiting for a new washer, plus, modifying just that washer probably would not be enough.
So, we trimmed 2 mm off the rear edge of the prop and 5 mm from the hub itself in order to set the prop perfectly on the shaft contacting the original suzuki washer (stopper) in the way it was supposed to. The front washer or the nut also need to be thinned about 2 mm. That's all.
Today I installed the prop and now just waiting for good weather to test it, it's been blowing about 10m/s (22mph) for two days and the forecast doesn't look good until the weekend.
here is the only picture I have , will make some more later.

[vkmaynard]

Stefan

Which prop are you trying?

Victor

[Stefan]

Victor,
i was talking about:

Solas RUBEX HR4 9453-135-13 Stainless Steel Boat Propeller with RBX125 hub.
thats 4x13.5x13.

if it acts similar to your experience with 50hp I should be fine, I don't want to lose any rpm due to the 4th blade.