rooster tail from hydro foil

first time on this site and gotta say,wish i had of found it earlier!!!!!! i Just got a new second hand boat 3 months ago and seem to have troubles with a rooster tail out the back of the motor when on the plane. it doesnt matter how i trim the motor it will not disapear..... i have heard that maybe the motor needs to be lower,but the motor hasnt moved since new,so i dont think it is that...i took it back to the dealer and test run it with him and he said it was nothing to worry about,but looking behind when motoring and seeings this water coming up from behind is starting to **** me off when i have never seen it on another boat.... it's a 96 model 70 evinrude on the back of a stacer 4.75...... does this foil need to be on there, i think i would like to keep it on,so any suggestions on how to fix would bee much appreciated..<br /> happy boating

Re: rooster tail from hydro foil

I would take it off and see how it does. Only 4 bolts to check it out. I wound up taking mine off, cause it interfered with my fishfinder by throwing so much spray at the transducer, that it disturbed the smooth flow of water to it. This is just one of the results of having the fin on there. I swore by them before, but not anymore. Have not lost any performance with it off, either. They do spread out the wake of the motor, so that does not suprise me that you are seeing what you are seeing.. Some boats work well with them, some don't. Consider smart tabs if you have trouble getting on plane after you remove it. They are cheap, result in better stability while underway and I've heard nothing but fantastic results with them installed. Nautijohn on hear, can fill you in on the details. Hail him and he will explain... I doubted them at first, but everyone can't be wrong who use them...

Re: rooster tail from hydro foil

Actually the motor needs to be a tad higher so the foil is out of the water when fully planed. Do as Rick suggests and try it w/out the foil.

Re: rooster tail from hydro foil

I had that same type of thing happen when I tried the "Sting Ray" brand of foil. it was caused by <br /><br />1. The Sting Ray foil sits on top of the cavitation plate. <br /><br />2. Is a one piece foil. <br /><br />3. it's the part that connects the 2 halves together that actually caused the roostertail.<br /><br />My solution was. <br /><br />I filed down the middle so that the water that wassn't forced up. I put a gradual slope from the front to the back in the middle.<br /><br />Hope this helps.<br /><br />Craig

Re: rooster tail from hydro foil

Anytime a fin causes a tail, the motor is too low. The fin is doing what its intended to do. Its a tool that allows you to raise the motor to improve efficiency.