Fish to Water toys prop change

[imported_Ady]

I currently run a 17" pitch prop on my 115 Merc 4s - 17'6" Alum Princecraft Pro Fish. All works well, I'm happy with top end and overall control and handling of the boat. But ......

Last year I tried Wake Boarding - the 4s sucked at getting the rider up, no hole shot. We had to sit everyone up front and even that was still poor. It has been suggested by many that I drop down to a 15" pitch to remedy this. Is a 17 " 4 blade a better option or a 15" 4 blade ??

I would swap the prop back when in normal use.

Thanks

 

[WillyBWright]

Re: Fish to Water toys prop change

The 17 four blade would be worse than the 17 three blade. The motor would work harder pushing that fourth blade. A 15 four blade would be about the same as a 17 three blade, probably a little better.

 

[evin268fs]

Re: Fish to Water toys prop change

wakeboarding takes less motor than skiing to get out of the water, almost none at all in fact. I think you should work on your technique getting out of the water.

Start with the board resting in front of you. As soon as the rope is tight, put pressure on your dominant foot, allow it to track to the back and ride it up, like you were getting up on one. Don't let the board plow. With the large surface area you should come right up before the boat is even on plane. If the 115 is struggling with with a 17 pitch prop, the border is definatly not allowing the board to track and plowing. With the 1

If you are fighting it on your way up, the 15 will only pull harder and most likely over.

 

[evin268fs]

Re: Fish to Water toys prop change

Forgot to ask are you trimming all the way down before taking off? No boat will want to plane out if you are towing and not trimmed down. You will not need to go down to a 15" prop usually unless you are towing a 200+ slalom skier, deepwater starts. Even then Probably should still be able to get up with a 17 will just have to drag a bit. ...

 

[imported_Ady]

Re: Fish to Water toys prop change

Forgot to ask are you trimming all the way down before taking off? No boat will want to plane out if you are towing and not trimmed down. You will not need to go down to a 15" prop usually unless you are towing a 200+ slalom skier, deepwater starts. Even then Probably should still be able to get up with a 17 will just have to drag a bit. ...

I Am trimmed down, the boat really struggles to get moving - another thing that may help this discussion, I am towing off the cleats!!

 

[evin268fs]

Re: Fish to Water toys prop change

How much extra wieght do you have in the boat. This may be an issue. Normally best to ski in groups of 3 or 4, people,one of which being the skier. I still don't think there should be a problem, I am a 200 lbs, and get up behind a 18'6" glass boat, with a 18 Raker (not a great towing prop), with an old evinrude crossflow 115, can come up easiest with a wakeboard, little trottle, (maybe 1/2 to get up) still pretty easy on two (full trottle and back off), have to drop some pitch to get up on one however.

Maybe get a 15 while you work on your starts and then use it as your spare. With the 15 it is great to tow with, but you get tired of changing back and forth, cause you will want the speed of the 17. Once you become experienced I am positive the 17 will have all the power you need.

 

[imported_Ady]

Re: Fish to Water toys prop change

How much extra wieght do you have in the boat. This may be an issue. Normally best to ski in groups of 3 or 4, people,one of which being the skier. I still don't think there should be a problem, I am a 200 lbs, and get up behind a 18'6" glass boat, with a 18 Raker (not a great towing prop), with an old evinrude crossflow 115, can come up easiest with a wakeboard, little trottle, (maybe 1/2 to get up) still pretty easy on two (full trottle and back off), have to drop some pitch to get up on one however.

I had 3 in the boat at the time, It has been sugested to me that the problem lies with the 4 stroke, no hole shot. I don't have a spare prop at the moment so I think I shall go with a 15 3-blade to give me that spare and to put on when I go out to play. I don't think I will be wake boarding more than 4 times a year so the swap should not be an issue.

Thanks for the replies.....

Maybe get a 15 while you work on your starts and then use it as your spare. With the 15 it is great to tow with, but you get tired of changing back and forth, cause you will want the speed of the 17. Once you become experienced I am positive the 17 will have all the power you need.

 

[evin268fs]

Re: Fish to Water toys prop change

Never skied behind a 4-stroke, couldn't tell you much about their holeshot.

 

[kenmyfam]

Re: Fish to Water toys prop change

Pitch down and try it 3 blade. It will always be a good spare anyway. It certainly wont get any worse by doing this. How are your WOT rpm's ?? compared to the max recommended rpm's ??

 

[roscoe]

Re: Fish to Water toys prop change

Pitch down and try it 3 blade. It will always be a good spare anyway. It certainly wont get any worse by doing this. How are your WOT rpm's ?? compared to the max recommended rpm's ??

Yes, this is the question that needs to be answered.

What is the recommended rpm range for your motor?
What are your wide open throttle rpm's.
How much weight is in the boat?

 

[imported_Ady]

Re: Fish to Water toys prop change

The Max RPM from the website is 5800-6400, the handbook says 5000-6000. At WOT I get appx 5800. From all I have read here, it looks like going down a pitch should be okay......

 

[woodchip]

Re: Fish to Water toys prop change

I have a lund with a merc 90 4s.wateskiing is fine with it.The dealer was very specific about not towing anything with the cleats on the gunwales.I know that for wake boarding you want a higher tow point but I won't do that with my boat.
But I do hope to try wakeboarding with it this summer