Fishing Forum

I took the day and tested props for my boat today.

Lee at lees marine is the best. He let me take props from his shop, over to hyrum res and run them around on my boat, no charge!

I got to test all different pitches, dias, and blades.

Its amazing how different just on pitch can make.

My engine is set to run at 5600 rpm max. A 17 pitch ran me low, around 5200 rpm. A 19 pitch ran me high, 6000 rpm. But a 18 pitch is just right at mid elevation lakes. On willard I may not quite get to run full out to keep the rpm at max, but on strawberry, I will loose a couple hundred rpm and still be in good operating condition. I tried out a 16 pitch too, yikes! 4800 rpm. That will do some damage over the long haul.

So its a turbo, 2+2, four blade, 18 pitch stainless for me!

It was really nice to get to try out all the props and see how they work specifically with my boat weight, size, ect.

Much, much better than going down, buying a prop, trying it, taking it back, paying $30.00 to excahange it, trying another, paying the difference, taking it back, paying another $30.00 to exchange it, trying another. Or just buying one and hoping you get lucky and get the perfect prop on the first try.

Plus lee gave me a big book on props to read last week so I would be fully educated when I came up today to test them out.
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Hey predator, how does a person know how many rpms a paticular engine is supposed to run at, you made reffrence to 4800 as troubble in the long run for your motor, And also how does a person measure the rpms that a motor is running at while stearing a boat, maybe a dash mounted guage or something, My boat is a 1968 dinarsaur 17 and a half foot deep V style boat. I'm kind of new to the fine tuning of the boat but want to learn to keep it running top shape. Any info on this subject would help in the overwhelming responsibilities of boating





Paul
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[font "Comic Sans MS"][size 3]Hi LineDropper![/size][/font]

[font "Comic Sans MS"][size 3]Give Lee a call and tell him what year and make your motor is and he can look up your max operating RPM. From there it's getting the prop size and pitch to match your motor and boat. [/size][/font]

[font "Comic Sans MS"][size 3]When I brought my boat up from the coast, I had to go through the same stuff Predator did. I ended up going with a stainless steel Turbo performance prop with a 17 pitch. I can use the prop anywhere in Utah but really have to watch my RPMs when I hit the coast.[/size][/font]

[font "Comic Sans MS"][size 3]Also aluminum and stainless steel props respond differently. There is a lot of flex in an aluminum prop where S.S. doesn't flex as much. A good S.S. prop can give you and extra 300 RPM over an aluminum of the same diameter and pitch. If cost is a consideration S.S. may not the solution because the S.S. prop is a lot more money but if you're looking for performance then stainless is the way to go. [/size][/font]

[font "Comic Sans MS"][size 3]A stainless steel prop can bite with a lot less water than aluminum. We had to raise my motor almost 3" to fine tune the motor/prop to the boat. When the aluminum prop was on, I would dive the boat into a hard turn and the prop would break loose but by just changing to a s.s. prop I could full throttle thru all turns without the prop breaking loose. There's that much difference.[/size][/font]

[font "Comic Sans MS"][size 3]Also another thing to think about. If you hit your prop on the bottom, it's real easy to screw the prop's pitch up even stainless steel. Some folks don't bother having their prop checked after hitting bottom, especially if it doesn't have obvious damage but you can drastically change the performance characteristics and flatten out the blade's pitch, causing a seroius degrading of the prop's performance.[/size][/font]
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[size 1]Ok, I'm going to reveal my ignorance, but it won't hurt too much because it isn't the first time.[/size]

[size 1]"I got to test all different pitches, dias, and blades." [/size]

[size 1]Not familiar with the term "dias" please explain.

"My engine is set to run at 5600 rpm max. A 17 pitch ran me low, around 5200 rpm. A 19 pitch ran me high, 6000 rpm." [/size]

[size 1]If one is running the boat at wide open it would seem that the rpm would decrease as the pitch went up. What am I missing here?[/size]
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[font "Comic Sans MS"][size 3]Dia = Diameter or diameter of the prop in this case.[/size][/font]

[font "Comic Sans MS"][size 3]All other things being the same, you are correct, Kent. You pitch down to increase RPM. You pitch up to decrease RPM.[/size][/font]
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yeah kent, I screwed up when I was typing. You have to swith the pitches on the 19 and 16 rpms. I just got in a hurry typing and had so much info in my brain after today I got them switched.
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