Bigger motor than rated for - same engine weight

[toehlke84]

I have a 2015 24' Aqua Patio 2400 CB 2-toon pontoon w/ sea legs and a 150hp ETEC (E150DGL). I'd like slightly more speed for the kid's tubing and skiing. What if I upgraded the motor to a 200hp ETEC (E200DGL) of the same weight? The boat is rated for 150 max but isn't that mostly based on weight the transom can handle? I don't care about insurance or coast guard or regulatory concerns. I just want to know if it will perform and give me the speed increase Im looking for. Boat is used on a quiet (medium sized) lake in MN.

 

[ahicks]

Not familiar with "sea legs"?

With no weight increase, I'd be tempted to make that move, but not before the engine pod attach points were inspected and possibly beefed up a little.

Just consider that when pulling, especially with that kind of power on tap, this boat is not going to be real good at turning in any kind of a hurry. A sharp eye forward, assuring plenty of room to get the thing shut down in time if necessary, would be important.

I'd also start shopping for something like a tri toon with lifting strakes, or maybe even an outboard powered deck boat. A conventional 'toon, even one with the kind of power you're considering, will NEVER be a good ski platform.

 

[Chris1956]

Boats are rated for HP based upon a formula of length and beam. I do not think engine weight is a factor. Hull design is a factor.

If you increase HP above maximum, some boats will be come unstable. I have no experience with pontoon boats,so I cannot outline the characteristics of instability to look for.

I think your question should be.."what are the characteristics of an overpowered pontoon boat".

 

[JimS123]

The safety factor is more than just weight, its also how much force is applied and how unstable (dangerous squirrely) at the speed you are trying to achieve..

I might consider the swap if it were a HD FG boat but just look at the attachment points on a toon. Not to be over-stressed.

Moot point anyway - ETec is outa bizness and even if you could find one, what about future parts and service?

If the 150 can't get the kids fast enough, you are either trying to go TOO fast, or you have too many people in the boat. Your best bet would be to get a prop that optimizes the engine performance (i.e, max rpms). A 24' toon with a 115 should be able to do what you want if the prop is the correct one for your application.

 

[Scott Danforth]

since the max tubing speed for kids is considered 24mph, your 150 should get there without a problem

the issue isnt weigth on a motor, its the torque generated by the thrust that is trying to pry your motor pod off the boat.

ahicks sea-legs are a hydraulically powered 4-bar linkage setup that when lowered raises the pontoon out of the water a bit. sort of a self-contained pontoon lift.

the problem is that they add drag to the 'toon because they are about as hydrodynamic as a brick

 

[ahicks]

Scott, thank for the explanation. I thought that's what they were, but could not connect them to his question. My buddy, with a new 300 hp tri-toon, found that the water at his dock was a bit too shallow for reliable operation on/off a 'toon lift. He's considering a set of the "sea legs" as a solution for that problem. Nice to have that kind of a budget.....

I agree this 150 on a 24' conventional 'toon should offer plenty of pulling power and speed for tubing or skiing (IF propped correctly, another good point)). The only reason I can think of for wanting more HP is if he's trying to pull every kid in the neighborhood, along with a few adults, at once! That's fun until somebody falls down/off, Then you have to clean up the mess of bodies left everywhere, get them organized, then go again. Fun, I'll admit....