# Will a hydrofoil help level a small boat with a 2.5 hp motor



## nlester (Jun 13, 2012)

I have a 10' mod v jon boat with a 2.5 hp mercury. Will a hydrofoil help level a boat with only 2.5 hp? I have the trolling motor and the battery in the front of the boat. With the gas engine, the stern squats right down. 

If I am going a long distance, I put on a handle extension and sit in the middle of the boat. I prefer to be in the back of the boat for better control. 

Here is a hydrofoil listed for 1.5 to 40 hp motors. Do you think it would be worth while? All the comments that I have seen are for 9 hp motors and above.





https://www.cabelas.com/catalog/product.jsp?productId=736992


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## JMichael (Jun 13, 2012)

Although I've never seen one on a motor that small, I can't imagine that your boat would move fast enough for the foil to be of any help. Your best bet will be getting the weight distributed correctly to achieve your best speed and I'm guessing that's going to happen with you sitting on that middle seat and playing with the position of the battery and fuel.


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## Frogman Ladue (Jun 13, 2012)

Sounds like your trim is way off...


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## nlester (Jun 14, 2012)

My 10' foot jon boat only has 2 bench seats, midship and aft. I keep most of my weight forward of the midship seat. My trolling motor and battery are as far forward as possible. I only keep about 1/2 gallon of gas aft of the rear seat. The problems are the length of the boat, the 2.5 hp mercury engine and me sitting on the aft seat. This is not normally an issue because I try to keep close to shore and not be out when the winds are going to be above about 8 mph. If I get caught in heavier wind, I kneel down behind the midship bench to trim the boat and keep as low as possible until I can get to shore. I had one bad experience when a weather front came through really fast and I was stuck in a following sea because the only way back to shore was with the wind behind me. In retrospect, I probably should have tried tacking so that the wind was never directly behind me but at the I time I just wanted to get to shore.

I would really like to be able to bring the stern up but I don't see any way to do it other than lift the stern with a hydrofoil or add more weight to the bow.


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## GYPSY400 (Jun 14, 2012)

Frogman Ladue said:


> Sounds like your trim is way off...



X2
2.5hp motors aren't designed to plane out, so the hydrofoil would be a mere decoration.


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## Bigkat650 (Jun 14, 2012)

All that foil would do is create more drag on your boat and cause you to go slower. It sounds like you are currently doing about all you can with that little 2.5hp. If you are looking to just get on plane to cruise a little nicer, you could think about upgrading to a 5 or 7hp. I'm not sure what your boat is rated for, but I would keep it at 9.9hp or less. I just don't think a 2.5 is quite enough motor for your set-up if your looking to cover larger distances a little quicker.


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## nlester (Jun 14, 2012)

Thanks - That's what I thought but I couldn't help but ask. 

I'll just enjoy what I have because right now, I don't want to go any bigger.

I'll still try out new ideas but mainly improving what I have.


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## Kismet (Jun 14, 2012)

nlester? 

Doesn't help at all, but it was simple and fun. Sportsman's Goop and lexan, no holes drilled, and the sunnofagun still hasn't come off.

https://i275.photobucket.com/albums/jj297/Kismethimself/Boats/reartransomreplacement.jpg


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## nlester (Jun 15, 2012)

OK - I am not saying that I would do this but I am considering my options. I don't want to add weight to my bow and I don't have any weight to move forward except my own. Cabelas sells pods to attach to the stern of your boat and increase the boyancy of the stern. I am thinking of creating my own. I do not want to have them attached to the stern all the time but under certain conditions, I would want something I could attach when needed to improve my trim. I am still considering my options. It could be like the yak where the stern splits and the halves slide out to improve the stablity. I don't know. Just thinking. 

Pros/Cons??

https://www.cabelas.com/product/Bea...cts&Ntt=pods&WTz_l=Header;Search-All+Products


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## Captain Ahab (Jun 15, 2012)

Kismet said:


> nlester?
> 
> Doesn't help at all, but it was simple and fun. Sportsman's Goop and lexan, no holes drilled, and the sunnofagun still hasn't come off.
> 
> https://i275.photobucket.com/albums/jj297/Kismethimself/Boats/reartransomreplacement.jpg





It look like you have it on backwards


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## fool4fish1226 (Jun 15, 2012)

Pods would help with your situation, it maybe worth a try. Let us know what you end up doing.


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## reedjj (Jun 15, 2012)

For the price of those pods plus the added cost of welding them on you would be much better off getting about a 5hp short shaft outboard. A 4.5hp to 9.9 would fix your problem like bigkat650 stated. An old 6hp or 8hp merc would be just right. 

I'm gonna get those pods for my boat though.


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## Ictalurus (Jun 15, 2012)

reedjj said:


> For the price of those pods plus the added cost of welding them on you would be much better off getting about a 5hp short shaft outboard. A 4.5hp to 9.9 would fix your problem like bigkat650 stated. An old 6hp or 8hp merc would be just right.



I agree with reed. Also, it seems you're considering putting a good bit of $$$ into a 10' tin. Unless there is a strong sentimental attachment to the hull, i'd fish it as is and save the money until you decide to upgrade. Hang on to the 2.5 though, it will make an excellent kicker on a larger rig. I had a 12' V-hull and my 8 HP 'Rude would get it moving if I was in the boat alone, two people it would slow down a bit.


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## nlester (Jun 15, 2012)

Thanks - I'll think about it for awhile. I am not much on long term project boats but I enjoy tinkering around. Since it sounds like they would work, I wil try to come up with something as simple as I can. I'll play around with some prototypes to see how small they can be and still get results and I'll think about how to attach them. They will not be permanently mounted, if I make them. I just want to put them on when I might need them.
The 10' boat is a way to get on the water and still store it in a place in my garage that lets my wife park her car and me keep in the budget. On the water, I am not in a hurry to get some place and the weight of the 5 hp would add to the problem.
For bigger water, I go out with friends.
I'll let you know what I come up with.


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## Kismet (Jun 16, 2012)

Captain Ahab said:


> Kismet said:
> 
> 
> > nlester?
> ...



Hey Captain,

I checked with the designer, and he said, "Nope, just how I planned it."


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## nlester (Jun 16, 2012)

Frogman Ladue said:


> Sounds like your trim is way off...


Frogman Ladue, your are a little understated. Knowing nothing about boats, when you said trim, I thought weight distribution. After a couple of days, I started to think that maybe you meant something else. Okay, I can't raise my motor but since I can't plane and my calvcation plate is only good as a step if I fall in, that should not make any difference. I looked my motor over really well and I found a way to move the prop 1/2 a hole closer to the transom. I'll try that out tomarrow. If that doesn't work, I'll try moving the prop forward with shims on the transom to see if that makes any difference. Whither this works or not, thank you for pointing me in a direction that I had not considered.

I am still thinking of ways to improve my flotation on the transom. It is only a 10' er 2.5 hp but it is all I have to play with right now. I have more time than money.


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## acabtp (Jun 17, 2012)

nlester said:


> I am still thinking of ways to improve my flotation on the transom. It is only a 10' er 2.5 hp but it is all I have to play with right now. I have more time than money.


use your time to make some money then so you can just get a bigger boat and/or motor. modifying that 10' will still leave you wanting a bigger boat, and you won't be able to sell it for as much as if you leave it be.


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## nlester (Jun 18, 2012)

GYPSY400 said:


> Frogman Ladue said:
> 
> 
> > Sounds like your trim is way off...


Thanks - By putting the pin in the second hole from the bottom, instead of the bottom hole, it let me move the propeller 1/2 hole closer to the boat. This got the results I wanted. My boat sits almost the same under power as it does sitting still.

Normally, I keep in the leeward arm of the lake on days like today but I went out in the open lake. In a 10+ mph head wind, my bow barely lifted, I got a lot of spray but still had enough freeboard at the stern to feel comfortable. An easy solution for something I was trying to make complex.

By keeping it simple, it still lets me strip down my boat, put it on a dolly and put it in the water where there are no ramps. None of my changes are permanent. It is still a plain 10' jon boat when I need it.


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## J.P. (Jun 18, 2012)

with the motor tilted that way, your bow will stay down, but take care not to stress the little motor too much. alternate between WOT and half throttle. running it that way is more stressful for the motor because instead of only pushing your boat forward, it also has to push your transom up (and therfore your bow don). you'll probably notice a drop in the performance and fuel efficiency (as if that matters on a 2.5hp). 

good that you figured it out on your own. i was gonna suggest it because we're in the same situation. i run a 2hp on a 13ft semi-V (but i've upgraded to a 6.5).


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## nlester (Jun 19, 2012)

Thanks for the tip. I try to treat the engine like my motorcycle. The difference in speed between full throttle and 3/4 throttle is hard to tell, so adjust your throttle accordingly. Back off periodically to let the oil get to the rings and enjoy being on the water. I hope I understand a little more about what is happening now.

I think I am going to forget about the boat for awhile and just enjoy the fishing.


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## Mizzie (Jul 28, 2012)

Hello, Sorry to intrude on your thread but I have the same boat as you and have a question similar to your problem, rather than make a new thread, I figured I'd post here.

I also have the same problem of the bow raising and transom loosing free board under power with me on the rear bench. I have 2.2hp Mercury, which is actually faster than I was expecting when I bought it. I'm 210lbs and with me alone it moves pretty well, slows down with a passenger but still gets to the spots and beats rowing or charging trolling batteries every night. Anyways, Here's a picture of how my motor is trimmed, in order to fix the bow raise problem, which way did you tilt the shaft? (reference my picture, towards my boat(left) or towards the garage(right) ). I couldn't exactly understand what you meant. Also, I have about 2.5" before the bottom of my keel is lined up with my engines cavitation plate. I know on bigger engine boats that it's a big deal to have them lined up, however with a 2.2hp, would I see any difference in raising it to line up with the bottom of the boat?

And after you trimmed your engine so it would ride better with just you, did you have to change it back to the previous trim when a passenger is aboard ?

Thanks and sorry again for the thread intrude!

Mike


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## Buddychrist (Jul 28, 2012)

I found an actual use for a hydrofoil on my 25 hp mercury outboard!!! 

It holds the motor level when i lay it flat to work on it


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## nlester (Jul 29, 2012)

I moved the prop forward, closer to the transom. It seemed to help or at least I feel more confortable with it. It is just me 99% pf the time. If I did have a second passenger, I would expect that to improve my trim and I could probably move the prop back to help with performance. 

Once I was close, just a little bit of of movement seemed to make a big diffence. I was prepared to used shims if necessary. A search of this site and other sites provides some good suggestions so that you have a better understanding about what is going on. I don't know that my prop postion lifts my little boat as much as it does not push the stern down. How much your prop postion affects you boat position is better anwered by some others on this site who have more experience than myself.

As far as the stablizer goes, it makes a good step to get yourself back into the boat if you find yourself in the water. I found my self in a situation once andI was glad that I had read this suggestion some place. Yes, I always wear my PDF with a whisle attached and there are always a few boats on my lake. At my age, it is a long way up over the side to get back in the boat and using the motor got me back in. I could have left the boat on the lake and shore was not far away.


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