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Or does anyone think there may be another answer before I change the turn fin angle?
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Sucking the sponson down shows it's the sponson. Push the bottom of the turnfin towards the bow 1/16" at a time until it stops sucking down, that will also take care of the hard turning to the right.Comment
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Had the same problem with my gas one. Got a new Dick Tyndall turn fin and dropped the rudder assemble all the way down as deep as I could get it. Made the boat a pleasure to drive. I also had toe in on turn fin sponson 1/8". The boat was also very prop sensitive. Ran a 2716/2 20* rake/ make sure you shim the strut to 90* as if it is a Zip strut it had or has negitve machined into it. Hope this helps,JerryComment
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Spoke with zipp kits about an hour ago and they suggested I swap to a 1462 octura, kick the turn fin forward to get it to stop pulling that sponson down so hard and if that isn't enough then to simply rack the fronts of both sponsons to the left by loostning the collets and shifting the front over and that should stop it, I told him how bad it's crabbing when I try to make it run a straight line and he said it should gain another 8-10 mph at least once the problems are solved!Comment
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Been there done that just wanted to share my experience.What I posted ended my issues hope you work it out. BTW I would not even waste your time moving both sponsons just toe in turn fin side just the tip leave back alone and have the front 1/8" toward the tub.Comment
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so i moved the turnfin this afternoon as per zippkits instructions and the boat straightened up a bit but is definitely still pulling to the right and lost exactly 2.8 mph acording to the garmin 301 and im now a bit lost, i would have assumed that the boat nit pulling to the side anymore so bad would have sped the boat up a good bit but its lost a good bit of speed...Comment
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where might i find dick tyndall turnfin and i think im definitely going to check into shimming the right sponson...Comment
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Did you check the strut as Jerry suggested?
How much rudder do you have beyond the prop at it's lowest point?
What prop are you currently running? Sorry if it's posted and I missed it.
Where are the pics of the boat and the video?
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The strut is at a perfect 90 degrees with the hull so that's not it, I'm running a abc 2514 2 blade and I would say that I've got right at 3" hanging down past the very lowest tip of the prop...Comment
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Check your email Doug!Comment
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It's pulling between 180-190 constant amps and is maxing at 219.7 and getting to almost 165 degrees, it's also delivering 7400 watts of power, I know it should be going faster than what it is, just not sure what I should do to it next...Comment
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And the CG is at middle bolt hole on the turnfin if you look at the photo Doug.Comment
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I double checked my sponsons and the turnfin side is at exactly 9.25" front to back, the left side on the other hand is 9.25" rear 9.187 front, looks like I need to loosen the clamps and shift the front of the sponsons to the left and that will give me my 1/8" toe in on the turnfin side. I hope this works, I have the strut raised up about 1/4" off the ski because I was worried about what the amp draw would be initially and it's probably a good thing I did because of what the amp draw is now, would lowering it back down speed the boat up more and create lift and get the ski off the water or will the ski always be on the water no matter what with such a low pitch prop, the instructions say to drop the strut onto the ski but we are also talking about gas setup instructions where there is no such thing as amp draw...Comment
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would be willing to bet its the sharpness of your turn fin. if its the same fin in your picture ( all shiny ) its sharpened wrong. the fin should be sharpened similar to a rudder blade. tapered, not just rounded off. is your rudder an aluminum bar with the leading edge just rounded off? I would taper the leading edge back at least half the length of the fin (front to back) to verify your problem just remove the fin and try one run. turning at slow speeds . 3- blade props usually pull to the right and really load the motor. I use a 3 inch belt sander to sharpen fins. clamp it sideways to my table. good luck. your rudder looks too long. just raise up on transom. on takeoff you are dragging the top of the rudder blade in the water.Comment
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