would 20hp work on this setup?

[simplystressed]

good day. I'm considering a 20hp 4 stroke tiller on my 14.5ft fishing boat. total weight for boat plus people/gear/batteries/motor etc is likely over 1100lbs. rated for 30hp. Would a 20hp plane this setup and what kind of top speed would it get?

Thanks

 

[tomhath]

Re: would 20hp work on this setup?

I have a 14' aluminum runabout that a 20hp planes easily with three people. But I'm at least three hundred pounds under your weight and the hull shape will be a factor too. I'd guess you're close to the limit of what that motor could do, speed is not likely to be more than mid-teens. I use the boat on a lake restricted to 20hp so it was an easy decision for me.

 

[WN2712NJ]

Re: would 20hp work on this setup?

Probably marginal. General rule of thumb on this board is go for 75% or more of max rated HP. So a 25 would probably be better. OTOH, we use a 20HP 4stroke on our 14 foot tinny and it works fine, but that boat is really light, probably around 300 pounds before passengers and the engine itself. It planes off easily with 2 or 3 aboard, struggles a bit with 4, but will still plane and hit the upper teens. With only one aboard, 25-27 mph is possible.

One issue you may run into is that amongst the motors that I am aware of, most 20's are two cylinders, and 25 and up are 3 cylinders. So there is a significant jump in the weight of the motor itself. That was part of the reason I went with a 20. The other reason was that the teen-agers get to run it by themselves, and I didn't want it to be overly powered.

 

[Home Cookin']

Re: would 20hp work on this setup?

it depends to a great deal on the hull design. weight is not the determining factor. a carolina skiff or jon, no problem; a trihull would be a pig.
batteries? how about a pull start and no batteries? why not one battery?

and 14' is good for 2 people fishing--are you taking more?

 

[bonz_d]

Re: would 20hp work on this setup?

This is the issue for me with small boats and 4 stroke engines. Weight to hp ratio. As said the comparision between the 20hp and 25hp weight because of the added cylinder. On these small light fishing boats one doesn't want a bunch of weight hanging off the stern. At least for me I want to keep the draw as shallow as possible. Which to me is the whole idea behind a small fishing boat. To be able to access those shallow back bay areas w/o worring about taking out a prop or lower unit.

Then if I want to go faster or carry more people I'd get a bigger boat but then lose the shallow access. Trade offs!

 

[simplystressed]

Re: would 20hp work on this setup?

thanks everyone. my big concern is will it plane. if I only get around 20mph that is fine by me. a 30 would be sweet but quite a bit more $ and weight to add on the transom.

 

[Jerry_NJ]

Re: would 20hp work on this setup?

I put two people and a Westie (20 pound dog/avatar) in my 14' and it can't plane..oh, I'm limited to 9.9 HP on the two nearby lakes I use.

More to the post, what is your boat rated at weight-wise? I think mine is about 700 pounds, that would be about three my size if nothing else was in there. What does a 20 HP 4-cycle weigh - 150 pounds?