hydrofoil fin

[Brento311]

I am considering getting a hydrofoil stabilizer for my old evinrude 9.5 hp. Can someone tell me what exactly the fin does, and if it will help the performance of my motor and boat? Thanks<br /><br />Brent

 

[Ross J]

Re: hydrofoil fin

Hi there Brent311,<br />Its my opinion that a fin is helpful for a number of things but I'm only used to them on bigger motors so someone else may well help here.<br />What I can tell you is the effect they have on a boat and motor.<br />First they help the boat 'sit' just right in the water. <br />Then there's the quicker holeshot achieved by the lift they produce.<br />People often mention fuel savings and I can claim to have averaged 15 to 20 % better with a "Doelfin" on my 85hp Johnson.<br />You are also able to achieve a slower planing speed which may seem silly but there's times when you want this without 'sinking' back into the hole.<br />If there's any negative effect it could be in a lesser top speed, in my case this didn't matter as I don't travel at top speed anyway!<br />I have to say that I don't know what effect this would have on a 9hp motor.<br />Hope this helps,<br />Ross

 

[Boatist]

Re: hydrofoil fin

Brent311<br />For the most part I agree with ross. The fin will lift the back of boat and bring the bow down. It allows the motor trim to have more affect on the boat. In general it will cost you a little fuel mileage and top speed. When it lift the back of boat bow comes down which means more wetted surface slower speeds and more fuel. While this effect is minor do not think it will be faster and get better mileage. Every sales flier I have seen clame both. There is one place where it will save you fuel. If you are out to sea on a rough day and can not run fast enough to stay on plane the fin will let you slow down more and still stay on plane. In this condition running on plane instead of plowing you will get better mileage. I am not sure how much effect it will have on a 9.5 either. In general I perfer the hydrolic trim tabs that mount on the boat but on a small slow boat I do not think it would be worth it.

 

[Brento311]

Re: hydrofoil fin

Thanks a lot for the replies! It seems like I might need a doelfin, because when I am alone in my 14' jon boat, the front end comes up, and catches air. This causes me to go much slower than when someone is in the front pushing the bow down. It seems like that is exactly what I need. What are hydraulic trim tabs? Thanks<br /><br />Brent

 

[leeray]

Re: hydrofoil fin

hi there this is the first time i have been here i am having troubles with my 85 horse force motor it was running great and i stopped to fish and it died and it would start and run for about 10 seconds and die i am getting fuel and spark but dont know if it is enough

 

[Boatist]

Re: hydrofoil fin

Brent311<br />Hydraulic Trim Tabs mount on the boat not the motor. You have a metal trim tab on each side that is controlled by a Hrdraulic cylinder. Work better than the tabs mounted on the motor but cheapest ones are around $400. Main advantage is have more effect than single one on motor and can controll each side seperatly so can correct for listing and easy to adjust while under way.

 

[Boatist]

Re: hydrofoil fin

Leeray<br />You should go to the top and start a new post. I am sure you will get lots of help. My first guess would be fuel. squeese the blub. Really you should start a new post and give as much info as possible. The more you give the better you responces.

 

[ehenry]

Re: hydrofoil fin

Hey Brent, I had a 15 horse Evinrude that I put a Stingray fin on and it helped alot. The main thing I noticed was it helped on out of the hole performance and stopped the porposing. Hope you weren't affected by Wcom layoff.