2005 Fishin Barge Speed/Prop issue

[borntofish101]

Hey guys, I just got a 2005 Fishin Barge with a 75HP optimax motor. I can't seem to get the pontoon above 17 without a ton of prop slippage (I am guessing). I have tried 3 different props, a 14x10, 13.75x19, and 14x15. The 14x10 maxed out at 17 MPH at 5900 RPM, the 13.75x19 did 18 at 4000 RPM, the 14x15 did 18 at 5000 RPM. With the 14x15 It was doing 16-17 at 4000 and only gained 1-2 MPH at the 5000 RPM range. I have the motor as far down as it will go. I have played with the trimming to get the best performance I could get. I know its not a speed boat, I just want a nice cruising speed I guess the 16 MPH at 4000 RPM isn't bad. Any ideas on how I can fix this issue? Or does it just have to do with the speed and it being a pontoon?

 

[lakegeorge]

Re: 2005 Fishin Barge Speed/Prop issue

How long is the barge?

We have a 22ft Sweetwater with a 60hp Yamaha and get 21mph by gps.

 

[borntofish101]

Re: 2005 Fishin Barge Speed/Prop issue

Its a 21 foot Fishin Barge made by Tracker. All of my tests where done using a GPS for speed.

 

[borntofish101]

Re: 2005 Fishin Barge Speed/Prop issue



These are a couple pics of it the anti cavitation plate looks to low.

 

[The Rooster]

Re: 2005 Fishin Barge Speed/Prop issue

Hey "Fish", that Optimax is rated for 5750 rpm's max. I'd shoot for something close to that with an average load, and your normal cruising speed +/- 3500 -4500 rpm's falls where it falls. Kind of looks like a 13" pitch might put you in that neighborhood. Hard to tell if your too low with the motor. That can be so different from barge to barge. Good luck !!!!

 

[borntofish101]

Re: 2005 Fishin Barge Speed/Prop issue

Thanks. I was going to get a 13 pitch TP prop after I got this other issue figured out. Unless there us better choice for a prop.

 

[johnathan777]

Re: 2005 Fishin Barge Speed/Prop issue

I have a 21' Party barge with a 2002 75hp Tracker/Mercury 2 stroke.The book says 5250 rpm.Mine is not the Optimax. I get 22mph gps with the Merc 14x13 alum. pontoon prop @ 5200rpm. If I was you I would take off the foil or stingray.Since you are not planning it is just causing unwanted drag. I tried a precision propeller 14x13 stainless and lost 2mph and 400 rpm will try the 14x11 stainless next week and report my findings here.Great thing about precision propeller is for $39 more I got to test a prop and exchange it for a different pitch.

 

[Silvertip]

Re: 2005 Fishin Barge Speed/Prop issue

Try removing the whale tail. Engines on pontoons operate in very turbulent water. The whale tail may be adding to the problem. Pontoons also need to have the engine mounted as low as possible to avoid "ventilation" (you are not experiencing "cavitation"). Pontoons also benefit from pontoon specific props which have very large rounded blades. They perform better in reverse as well.

 

[borntofish101]

Re: 2005 Fishin Barge Speed/Prop issue

I added the whale tail after reading they can help with cavitation/vent issues. It really didn't make a difference at all. I got it up to 20 MPH (WOT) on the 15 pitch prop after raising the motor two holes. The problem is you read so much conflicting information on pontoons. Some people say lower all the way some people have luck with raising them. Some people love the 4 blade props some people say they are crap for a pontoon. Done a ton of reading so far. I just want to get rid of the slippage. I ran the slippage calculators I get 35-40% slip at almost every RPM range on the PowerTech prop 14x15 I have now.

I was thinking of trying a Turning Point 13 pitch prop or a 4 blade prop. I read the 4 blades lower slippage and increase MPG. Where do I find pontoon props? I thought the props for pontoons I wanted just had a 14 inch dia.

Let me know how your testing went on the SS.

 

[The Rooster]

Re: 2005 Fishin Barge Speed/Prop issue

Hey "Fish" I have been told good things from some pontoon owners about 4 blade props helping performance in some applications, but most I've talked to report a slight decrease in fuel mileage if that is a concern for you. Most of the bass fisherman I know report the same thing. More blade area and mass to turn through the water.

 

[Lawnmedic]

Re: 2005 Fishin Barge Speed/Prop issue

Mercury just announced a new 4 blade "pontoon" prop. The models for the smaller engines are out now, with the ones for the bigger engines are due this fall.