Re: High Thrust prop questions
I have a 9.9 merc 4 stroke kicker on my 24' crestliner great lakes hardtop boat. currently i am useing the stock prop. when things begin to get a little breezy the kicker struggles to keep the boat on course since the wind is pushing the boat around typically i will have to turn and go with the wind especially when trolling 1.5mph. i dont beleive h.p is the issue since the motor is only just above idle speed to troll and will push the boat about 6mph at w.o.t
Here are my qustions
1.Would i benefit from a lower pitch prop
2.would a high thrust low pitch be the way to go
Walleye Seeker:
I have a 2006 9.9 Mercury Pro Kicker on my Pro Line 241 Walkaround. At WOT it will go about 6mph without any wind factor. My boat weighs around 5,000 pound or so loaded, which may be similar to yours. The Pro Kicker has a 10" dia. by 7" pitch prop as standard, which I have. I experience a similar problem as you do when going into a headwind. However, my boat when idling, barely moves along with the prop I have now. This prop is said to be very flat as props go, and I believe it may be flatter than a regular merc 4 stroke motor. This makes it very slow trolling for its RPM of the engine.
I actually need more speed per the relative engine RPM because I typically troll for lake trout( 1.7-2.2mph), and some times for salmon, at from 3.5 to 4.5mph. I believe more speed would make any boat more quick to correct and off course bow heading, or wander that you experience. However, if you are walleye fishing, that is not desired. I have heard that dragging sea anchors can make the bow a little less easy to blow of course, but the trade of is that when they do get off course, it takes more to get them back on course. However, they might give you more time to countersteer before the boat gets off course so much from a gust that its hard to get back on course again.
As one replier to you suggested some for of rudder or even a sea anchor could be used to steady your bow heading. In this application, you could drag a sea anchor on one side of the boat, which would effectively push or pull the bow to the left or right with somewhat steady pressure as the speed of your boat would dictate. Then to counteract the bow from going in that direction, you could give some countersteer with your trolling motor, effectively negating the sideways pressure created by the sea anchor, which is actually acting as a sort of stabilizing rudder when combined with the countersteering that you induce by the trolling motor. The two of them work against each other, and the more they work against each other, the more of a stabilizing effect they will have on the bow wander from the wind gusts.
This will obviously make your trolling motor have to work a little more, but it sounds like it is not working hard anyway. As far as sizing the sea anchor, it all depends on your conditions and the distance that separates the anchor from the trolling motor. You would likely want to put the sea anchor on the oppposite side of the boat from the trolling motor, and as far back as you can toward the stern of the boat. If you cannot find a convenient and effective place to put it near the stern, without getting in the way of your fishing lines, you could mount the sea anchor on a small short outrigger arm that extends 4-6 feet out to the side of the boat, but it would need to be anchored somewhere on the gunnel toward the rear of the boat in order to get your best stabilizing rudder effect. You could experiment with placement of the sea anchor further forward on the gunnel to see what works best for the conditions you have.
This may sound a little involved, but if you experiment with this method, I bet you will eventually find yourself an expert at making flexible applications with your boat and the conditions on any given day. It is likely the best way to get the kind of stabilizing effect you want without trying to put some sort of large keel on the boat. That would seem to be less effective and less flexible to what I am proposing here. You can tie on or attach inexpensive sea anchors of all types and sizes at different places on the boat with some trial and error and believe you will get the results you want. I know it will work, the physics of the situation indicate that.
I will be getting a prop change that will allow more effective speed or distance traveled per revolution to help my motor work less for the speeds I need. Also, that will help me get back to port faster if I have my main i/o die on me like it did last fall on Lake Superior. So it will be a faster traveling kicker. When it failed I had to go a couple of miles in a 25-35mph headwind to get back to the harbor/port. It barely moved at all, probably going less than 1mph at WOT. I could have beached the boat on a rocky gravel shore elsewhere, but that would not have been good for my fiberglass hull.
I also have a 19 foot Starcraft Holiday, which I have used for several years previous to this Pro Line boat I just bought. It is a great boat, and I used the 9.9 on it for a few years. However, it is a lot lighter than the Pro Line, so the 9.9 moved it very well on a simillar windy day when the main engine died on me in the Starcraft.
Please let me know if you try the sea anchor/engine counter steer tactic with any luck. I know it will work to some degree, but it is very dependent on all of the factors and conditions of wind, anchor placement, anchor size, and your willingness to experiment. If you are like me, anything that bothers my fishing has a solution. It is just a matter of finding the solution and making it work.. As they say, necessity is the mother of invention, or in this case adaptation.
Clay Adams
