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Prop for Sport 15 Center Console, 60 Merc 2 stroke
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| theo |
Posted on 05/09/11 - 9:09 AM
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Hi all,
I'm finally tired of dumping all my gear on the beach and running solo with a couple gallons of gas. I need steeper pitch so I can haul some cargo and a wife or friend.  I have a healthy 60 Merc 2 stroke (1.84:1) on a 15' CC with a manual CMC jack plate. The prop is stock Mercury 15" pitch. On the salt water I get 5250 rpm and sometimes touch 41 mph by GPS (which I don't trust but it's a gauge at least), but the hole shot is weak and I bog down pretty heavily in sharp corners. I'm pretty sure 5500 is max rpm for that motor, but it wouldn't hurt my feelings to exceed that by a couple of hundred with very light loads in order to maintain performance at "normal" loads.
Here in Montana at around 3500' elevation I always notice a slight decrease in performance. And if I load the boat down it just plain doesn't work. For example, I just returned from a fishing trip on Fort Peck where I couldn't get over 4900 with 15 gallons of gas, 2 extra batteries (one of which weighs 120 lbs), a trolling motor, and some fishing gear. Some of that loss is related to jetting, I'm sure, but I'm thinking a lot of it could be solved with a different prop.
I think I need a 13" prop. Not sure what model, not sure what diameter, and not sure whether to go with stainless or stay with aluminum. I don't mind spending a little money if the stainless really will outperform the aluminum.
Hopefully you folks have some ideas. Thanks.
Edited by Tom W Clark on 05/09/11 - 7:19 PM
Ted
1985 15' CC, 1994 60 hp Merc (Wednesday built), 5" jack plate |
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| Tom W Clark |
Posted on 05/09/11 - 7:14 PM
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Yes, there will be about a 10 percent loss of horsepower at 3500 feet of elevation.
I recommend a 10-1/2" x 12" Stiletto Triad 3.5 for your boat This prop will perform like most 13" props.
Yes, a good stainless steel propeller like the Stiletto Triad will outperform any aluminum prop. No need to spend more that $200 on it either.
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| theo |
Posted on 05/10/11 - 7:22 AM
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Thanks Tom. I was hoping you would respond.
2 questions:
- I like top end and I do most of my boating at sea level. I wonder if the 13" would fill my needs any better?
- Is the Triad 3.5 a new model? I can only find Triad I and II online.
Ted
1985 15' CC, 1994 60 hp Merc (Wednesday built), 5" jack plate |
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| Tom W Clark |
Posted on 05/10/11 - 7:31 AM
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It's going to be tough to have one perfect prop for light loads at sea level and also heavily loaded at 3500 feet.
Yes, the Triad 3.5 is the new version (since 2009) of the Triad II.
The Triad 3.0 is the new version of the Triad I.
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| Tom W Clark |
Posted on 05/10/11 - 12:42 PM
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Ted -- Are you sure your 1994 Mercury 60 has a 1.84:1 gear ratio and not a 1.64:1 gear ratio?
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| theo |
Posted on 05/10/11 - 5:07 PM
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Sorry. I quoted from memory. 1.64:1 as per the stats I copied from outboardsales.com and piranha.com.
You'd think a guy would learn to stop trusting something as old as my memory is.
Ted
1985 15' CC, 1994 60 hp Merc (Wednesday built), 5" jack plate |
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| Tom W Clark |
Posted on 05/10/11 - 6:05 PM
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OK, that's what I thought. My recommendations are:
10-1/2" x 12" Stiletto Triad 3.5 for a load at 3500 feet.
10-1/2" x 13" Stiletto Triad 3.5 for sea level light speed.
If you only want to buy one prop, you'll have to decide which is best for your needs.
If you want one of those props, let me know, I can get you one.
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| theo |
Posted on 05/12/11 - 5:11 PM
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I'll take you up on it! I'm leaning toward light load at sea level and best top end, which means the 13". If it's too tall I can find a shop to detune it.
Or do you think it's easier to start with the 12" and tune it the other way if need be?
Or maybe stainless doesn't lend itself well to tuning? I'm only familiar with a NiBrAl (Nickel/Bronze/Aluminum) prop I had on a 150 tower of power many years ago. It went through a series of trial and error tuning, all aimed at top end.
Anyway, I'm two shakes from buying a prop from you. I'm leaving for the coast in two weeks. Any chance you might be able to get it to me by then? Assuming I make up my mind, that is.
many thanks,
Ted
camptideout@gmail.com
Missoula, MT 59804
Ted
1985 15' CC, 1994 60 hp Merc (Wednesday built), 5" jack plate |
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| Tom W Clark |
Posted on 05/13/11 - 9:32 AM
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Ted,
Delivery takes a week or less from the time I order.
Just send me an email when you decide what you're going to do.
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| theo |
Posted on 07/21/11 - 8:03 AM
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I'm back to civilization (and the internet) after a month and a half of working (and boating) on Puget Sound. Just wanted to drag up this old thread to shout out thanks to Tom. He sold me a great prop at a great price. I'll never go back to aluminum again. I bought the 13" because I was afraid of losing top end. What I got was virtually the same top end but the boat handles like a sports car now - it jumps out of the hole and holds the water on any turn at any speed in smooth, or chop, or rough water. My Mercury aluminum prop, although it's a 15" pitch, pales in comparison. I recommend Stilletto and I nominate Tom Clark for president.
Well, maybe honorary president of the Whaler junkies of the world. Many thanks Tom.
Edited by theo on 07/21/11 - 8:05 AM
Ted
1985 15' CC, 1994 60 hp Merc (Wednesday built), 5" jack plate |
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| Tom W Clark |
Posted on 07/21/11 - 10:17 AM
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I am glad that propeller has worked out well for you. Have you tried it at elevation back home in Montana? If so, how are the RPM?
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| theo |
Posted on 07/22/11 - 8:48 AM
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Might get a chance at Flathead Lake tomorrow. If so, I'll let you know.
I never did get to raise the motor; my jack plate bolts are frozen solid and I'll need to disassemble it here at home to get the adjustability back. I was at 5400 on the Sound with the cav plate about an inch above the keel. Can't wait to try another inch or even two.
Anybody know any performance tweaks for a 93 Merc 60 horse? Rejet the carbs? Tuned ports? . . .
Ted
1985 15' CC, 1994 60 hp Merc (Wednesday built), 5" jack plate |
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