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| Anyone running a 4 blade on their 1760? Im running a 3 blade 19 k series and it barely gets out of the hole with a full load. Top speed on 35mph. What are your rigs running. Thanks in advance.  |
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Posts: 3508
Location: Elk River, Minnesota | Hiya,
I'll help out if you'd like....
I do have a couple of questions for you regarding your rig. First, What are the Max RPMs and speed you get when you are fishing alone with just your gear?
I am assuming this is an Esox series of boat, and looking at the website, it has a bit of weight being #1400 and rated for 150hp. With a 115hp on the back, I would bet it will struggle with that particular pitch of prop even under lighter loads. My instinct would say you are well below the max RPM of 6000 on your motor, which really means getting a prop with a less pitch. Depending on those RPMs you might find a 17 pitch or possibly a 15 pitch might be needed, and you should be able to stay with a 3-blade design. The lower pitch will essentially get the stern to jump up quicker since more RPMs will be created in the lower throttle range, making it easier to turn the prop.
What a 4 blade prop would do is give you better hole shot and more handling capabilities, but you will loose top speed as well, not only due to a requirement of less pitch when you go to a 4th blade, but you also increase the blade surface area which increases the amount of drag in the water.
so...if you have the numbers and would be willing to divulge that information, along with a mounting height for the motor as it is mounted on the transom , a more thorough recommendation can take place. Lots of variables to consider that can affect the performance of the boat altogether.
Steve |
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| Steve, Thanks for the info. It is an esox series, 56oo - 5700 with just me in the boat, trimmed pretty heavy, top speed 40 mph. Motor is up one hole. I dont know if 3 blade will get me out of the hole well enough with a full load, that is where it really struggles. |
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Posts: 3508
Location: Elk River, Minnesota | Hiya,
I have no doubt in my mind that you are over-pitched by about 2 inches. If you drop to a 13-1/2 x 17 pitch in a stock aluminum, I would bet you will get out of the hole much easier and you will probably see a minimal loss in speed since you will be getting some needed RPM's at the top of the throttle range. If you went with a 19 pitch with 4 blades, I would highly doubt you would get out of the hole at all...the motor just is not strong enough with that much resistance in the water.
If you go to a 4 blade, you would need to drop another inch in pitch to a 16...possibly a 15 pitch. For really heavy loads, a 15 pitch would be needed. That is a very heavy boat for the horsepower you have on the back. You might be able to get away with a 4 blade 17 pitch along with moving the motor up another hole. If this is something that you would consider, I would suggest trying a solas 4 blade aluminum in a 13" x 17" configuration.
If you are in the twin cities area, I have a stock 17 pitch you could try out....
Steve |
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| Steve, Thanks so much, unfortunately I am in Michigan. I ran a 17 stock aluminum and could get the rpms but lost 3mph. I was hoping to run stainless to reduce blade flex with that heavy of a boat. Was looking at a Solas Titan4, in a 17, what do you think? |
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Posts: 3508
Location: Elk River, Minnesota | The 4 blade might be a bit much to turn in 17 pitch, but going that route you could gain the RPM's back if you lift the motor higher off the transom (which I suspect you could go as high as the motor allows). THAT will get your RPM's up at the high end, the hole shot at the low end, and wonderful handling. I'd say decent route to start.
If you do go that route, I would highly suggest finding a good prop shop (either online or close by) that would allow you to exchange props if that one does not work out. Many dealers have demo props as well, but many do not carry solas.
If you went aluminum from solas, you kinda get the best of both metals... The aluminum props are made by a process called "squeeze casting" where they acutally inject the molten aluminum under pressure rather than just pour the molten aluminum into a cast. This gives the blade more strength so it flexes less, and can be shaved thinner to create a more efficient blade. So...what you get is just a touch more flex than steel at the price of Aluminum. The blades are cupped and they hold really well. I just put mine back on (alcup 3) and it held up just as well as my michigan ballistic with just a touch loss of speed.
Steve
Edited by VMS 4/12/2010 1:02 PM
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| Thanks again Steve, great info. Any prop shops that you could recommend? |
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Posts: 3508
Location: Elk River, Minnesota | I know overtons online does exchange program, but I believe you pay the shipping for it, which can get expensive. Not being from Michigan, I would have to refer you to someone familiar with dealers out there, and I don't know of any...so unfortunately, I cannot help there. I have used Propline.com for purchases before and have not had any issues with them.
I'm also not sold quite yet on going 4 blade, although I do think with the weight of the boat and the power on the back it might be a good thing too...that comes with testing. I have this feeling that I think a highly cupped steel 3 blade might do really well too. Something like an older michigan rapture, stiletto advantage, or a powertech prop could fit the bill well.
Steve
Steve |
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