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Hello,

I have been searching the site, but haven't been able to find any information on this combination. We have a 2001 17' Montauk with a new 2010 Honda 4 stroke. We have a 13 pitch prop right now, but I don't think that it is right. Someone mentioned that a 17 pitch might be a better way to go. Just hoping someone has this combination or could offer input before I buy a new prop. Also, the motor is mounted 1 hole up. I am not sure if that is right either.

Thanks!

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Good god! How did you end up with a 13" pitch propeller on that boat?

The 2010 Honda BF90 and its 2.33:1 gear ratio and 6300 RPM redline will do best with a 19" pitch propeller if using a basic aluminum prop but will performa much better with a 13-1/4" x 17" Stiletto Advantage or Turbo 1 (the Honda Turbo, part # 08M60-ZW7-A10, is essentially the same propeller.)

At only one hole up the motor is far too low on the transom. I recommend it be raised as high as it can go.

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Thank you Tom! I purchased the motor off of a manufacturer picture boat. It only has a few hours on it and that is the prop that it came with. I also have a new 21 P aluminum mercury propeller, but that probably will not work.

How high up do you think I can you go in hole position? The motor was installed by a good local mechanic, but he isn't a whaler dealer. He is the one that menioned needing a 17.

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The BF90 has four sets of mounting holes so it can go up another 1-1/2". In other words, the mounting bolts should go through the lowest set of holes in the motor.

o
o <-- "One Hole Up" The mounting bolts are currently here
o
o


o
o
o
o <-- You want the mounting bolts here.

You mechanic may very well push back on this recommendation. Hold your ground and ask him to do it anyway; with the 13-1/4" x 17" Stiletto/Turbo prop it will perform MUCH better with better acceleration and less bow rise, better fuel economy, lighter steering effort and faster top speed.

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That is great to know! Wow, that is a big difference in height. The stilletto might not be in the budget this year. What is the avantage or difference between the 17 & 19 aluminum?

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You can buy a Stiletto for less than $250. You'll spend over half of that on an aluminum prop. Given the $5,000-$10,000 you just spent on the new motor, how can the extra $100 or so be considered an extravagance, especially when it has such a profound effect on the boat's performance?

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That is a good point, just the wallet is feeling lighter. If you are certain that the 17 stilletto is the right prop, I will probably go that direction. Thank you for all of the input.

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Tom,
I have read many of your comments on motor mounting height and have this situation. 1966 16' with 2 stroke yamaha. I have used the boat one time so far and it seems very fast and responsive. The motor is currently mounted with the bolts thru the top most holes and the cavitation plate is at the bottom of the keel line. This also results in the motor sitting on the splash well cutout. The second set of bolts are 6" lower in the splash well and seem to be threaded into tapped holes available for them that are part of the motor. On the motor also are slots that would receive a thru bolt with nut and washer, if the motor was raised several inches. Your thoughts are appreciated. Thanks.
Sorry yamaha is 90 HP

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Yes, I am certain the 13-1/4" x 17" is the right prop.

If can buy the Stiletto branded version is the Advantage 4.25 part # D811317 with a DE-507 hub kit.

You can also buy the Turbo branded version, but it will cost a little more money. If you want a chuckle, call your local Honda dealer and ask for a price quote on the aforementioned Honda Turbo in the same size. All three props are made by Precision Propeller Industries Inc. (PPI) and are the same design.

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mtown -- Your lower bolts thread into what we call the "Blind Holes" that are auxiliary bolt locations used when the lower slot in not accessible on boats with shallow splashwells. OMC pioneered the auxiliary bolt locations back in 1960 and Yamaha followed suit for a while.

The remedy is simple: remove the motor from the transom, fill those lower bolt holes and drill two new one that are on the BIA industry standard bolt layout. Read this article for a more precise description:

http://www.whalercentral.com/articles...icle_id=82

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Thanks Tom, I was reading that exact article a minute ago. It looks like I could raise the motor all the way up to the fourth hole and get the bottom bolts to still be within the splash well and use the very top of the motor slots. Is that too high in your opinion?For the record, my other 16 of similar vintage has lags at the lower holes and was just repowered after 27 years and I have never had issues with them.

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When we bought our Honda, the Honda Regional Rep recommended a Honda Titan Solas 13 1/4 15R Stainless Steel Prop, which is what we've got. Not a hard stats guy, but it's still going strong w/a great hole shot and smooth high speed cruising. Good Luck!

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mtown -- Yes you raise the motor all the way up after drilling two new bolt holes 6-1/2" below the top bolt holes. You will always be able to lower it back down a hole if need be.

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Dale - I also recommend you raise your motor 2-1/4" to its highest possible mounting position and switch to the 13-1/4" x 17" Stiletto Advantage or Turbo.

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Thank you Tom

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Tom - With a 90 Honda on a Montauk turning 6300 through 2.33 gears and 19" prop, what kind of top speed does that enigne produce. Seems pretty fast, way over 42 MPH?

A 2-stroke Merc 90, running the same gearcase and 19" Laser II prop, shows 42 MPH at 5500. That Honda must be one fast engine, something they are not known for.

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Larry -- I estimate a classic Montauk with a Honda BF90 should do about 42 MPH, just as you report the Mercury 90 does.

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In thinking about the motor height, my only concern is that the Chesapeake can be quite choppy at times. I just don't want to be too high. It would be great to hear from others with the same motor.

I am hoping that I didn't make a mistake getting rid of our 2001 Merc 90 2 stroke. I have read a lot of varied opinions on that. With a 2 year old it is nice having a quiet non smoky engine. The 5 year warranty is nice too.

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You won't be too high. If you are you can always lower it one hole. If you only move it up one hole then you'll never know if it would be better at two more holes up. You only have the two options from where you are now at one hole up.

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Then Tom, a much lower pitch prop would be needed on the Honda, as compared to the Mercury, to go 42mph at 6300? A 17 Stiletto runs like everybody else's 19? 800 RPM is worth 4" pitch? Which means the Honda should be running a 13 Stiletto or a regular 15"?

Or the Honda is lot faster than 42.

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Larry, check your math.

A 17" Stiletto Advantage running with 0 percent slip at 42 MPH is going to be about 6100 RPM which is perfect for the BF90.

A BF90 mounted all the way up on the transom should pick up a couple more MPH which will bring the RPM up too.

Remember, we are discussing the Honda BF90 not an old Mercury 90.

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Tom,

Thinking about going on the cheep for this fall and upgrading next year to have a spare. What is a good aluminum prop? I have been looking at some reasonable ones from Solas and also Mercury. Also, if you could let me know or pm me with a good place to buy. I have been struggling to find an advantage for 249. Thanks!

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I'd just use a 13" x 19" Mercury Black Max, part # 48-77346A45. List price is $165 but you can shop it down online. Here is one for only $125:

http://mercuryperformance.com/mercury...35055.html

But note that does not include the hub kit or delivery.

Amazon has one for $150 which includes the hub kit:

http://www.amazon.com/dp/B000QGLLMY?t...gu-a102-20

But you pay shipping on top of that.

Now you are telling me you want to buy an aluminum prop to save money? After you have invested thousands and thousands of dollars in your boat? And the single most important piece of hardware that makes your new outboard move your Whaler is the piece of hardware you want to save money on?

Dan's Discount props sells the Stiletto Advantage 4.25 with hub kit, for $249. I am not clear if you pay shipping on top of that.

http://www.dansdiscountprops.com/BuyN...advantage1

So you save $100 buying an aluminum prop from Amazon.

But if you could buy the Advantage 4.25 for only $240 and that included both the hub kit AND the delivery, why wouldn't you just buy one and be done with it?

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Here's some good deals on Mercury props. Hubbed and shipped for $120. total, mid -sized gearcase for 75-125HP engines. I think Merc hubs fit a Honda gearcase.

jacosmarine.com

This is the best price I have found so far. About $14 cheaper than Dan's.

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Thank you again! I have a flo-torq II hub for a Merc. Is the only difference between the merc and honda the prop thrust washer? If so, is the washer that I am currently using on a fixed hub prop the same thing? It would be nice to not buy another hub kit.

I will probably just buy the SS prop, I was just thinking about a back up. My dad buys marine surplus so it won't be problem to find a second prop. He left me a 21' with the hub kit and the 13' but those unfortunately don't work. I have an SS Turbo prop on my 225 opti and love the performance.

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$120 is very good from Jacos. You can also get the OE Honda branded 13" x 19" aluminum (which is nothing but a Solas with grey paint) for less than $90 plus shipping:

http://www.partspak.com/productcart/p...uct=362907

But aren't we splitting hairs here?

If you already have a Flo-Torq hub kit, you can use it with your Honda thrust washer and prop nut and buy the Stiletto for only $225, including delivery. Email me for details.

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I received my Stiletto prop today. The boat seems to run great with this combination. It had nice hole shot and good high end speed. The cruising speed felt perfect. The RPMs maxed out at around 5700 with a little tilt. I didn't want to run the boat too long at high RPMs because the motor only has about 6 hours on it so far. I am used to using a lock nut, so hopefully I tightened the nut and put the pin in properly. Looking forward to running the boat some more and thank you for all of the input.

I just read the manual and they recommended not tightening past a certain amount. Looks like I need to find a tourque wrench just to be safe...

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Nice. By the time you get the motor broken in and raised up to its highest mounting position on the transom you should see your WOT engine speed climb well over 6000 RPM.