The idea is fine, but the jet units will be very inefficient at the likely speeds you will get from this project. The basic advantage of that type of jet unit is based on a fairly narrow weight and top speed ratio, they are optimised for this particular function and nothing else. The intake, stator vanes and drive impellor will need changing to attempt to gain back the efficiencies. There are good jet units available off the shelf that allow differing gear ratios and impellor combinations depending on your engine choice - Castaldi for one. By far the cheapest option is to fit two large outboards (if the design can cope with them) but if you have nothing better to do and the money....
Yes two jets and a skilled operator will have some creative handling options - but you are still talking about a catamaran of sorts, and they are always going to resist any sideways force far more than a monohull. It's just part of the package with a multi-hull at near zero speed when trying to get them to dance. In a serious cross wind they still are quite painfull regardless of jet drives or otherwise - that's when powerful bow and stern thrusters are actually worth the hype.
I am sure it has already been done. I saw a jet ski motor in a john boat.
Btw jet ski motors do put out 250hp and more.
Yamaha fzr 1.8L 4-stroke superchargered regular gas biggest pwc motor - 210hp
Kawasaki 300x 1.5L 4-stroke supercharged prem. gas most horsepower - 300hp
Sea-doo RTX-260 1.5L 4-stroke supercharged prem. gas - 260hp
Honda aquatrax F-15x (2009, Honda hasnt made a pwc since) 1.5L 4-stroke turbocharged prem. gas 200hpHas anyone put a jet ski motor into the pontoons of a pontoon boat?
it's a novel idea,and just might work well.my concern would be sealing the pontoon breach and keeping it sealed.twin outboards on brackets would work better, be cheaper and easier to install and maintain. i saw where some guy put two 3 liter mercs on one and set the speed record at just over 70 mph.
Eeek! Why don't you just put a single outboard engine on the back. You'll also have to coordinate throttle thrust. What two JS motors amount to 500 hp? I don't know of any that small. Also consider that if it is that small, then it's a two cylinder, which is not allowed on all waterways. Good luck and boat safe.Has anyone put a jet ski motor into the pontoons of a pontoon boat?
500hp can't get that out of a big block chevy but give it a try U will need 2 as there are 2 toons
i forget what it is called, but there is a prototype boat that is powered in a fashion very similiar to what you are talking about that is in use already.
pretty sure it was a discovery channel show.
its apontoon boat, with a cabin suspended way up high, kinda like a bridge mounted on two shores over a river. dual motors, inline with the pontoons, but in a seperate part with a hinge to it that allows it to go up and down with the waves.
it was intended as a carrier ship, i think meant to carry small science type subs. drive right over it and lift it up out of the water.
i really wish i could remember the name of it or the program i saw on it on.
seemed like an improvement over your typical pontoon boat.
and would probably be an excellent thing for you to look at.
not sure how it steered though. i dont think it was all thrust steering (not sure if it was even jet drive propulsion), but i dont if it had rudders or where they were either.
does seem that attaching dual engine pods inline with the pontoons would be easier then opening up the pontoons and later resealing them around everything that must pass through.
would require a longer trailer, probably specially built or modified.
although, my main concern would be total weight limit, balance of weight (definetly be a bit rear heavy), and providing something solid enough for the push on it, as i doubt the pontoons themselves are designed to have even 50 hp pushing directly on them.
BTW, you are waying overestimating the power of your typical jet ski.
1.8 liter motors, even supercharged, dont put out 250 hp each. not on regular pump gas, and that kind of power would be INSANE on something so small and light.
i'm having diffuculting finding the acutal power listed in the specs of 2011 yamaha and sea doo waverunners, but its more like 150 hp or LESS.
much like a motorcycle, 100 hp is a lot more then you think whne you arent moving a ton or two worth of vehicle too.
i.e, my 16' alum hull goes 40 mph, more if i propped up and unloaded teh fishing gear, with just 60 hp.
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