Glen-L.com

I am looking at building The Delta Q. or the Jublee. (houseboat) will a jetdrive or even duial jetdrives power it speed is not important, but the DQ, is a plaining hull so it will need to plain. I am going to build 1 or the other and I do not want a prop looking to chew up the swimmers leg ot the manity that is swimming by.
Safty is the first concern.

I like the walk-around on the Jubilee but if your going to trailer it then DQ is going to be a better choice. I don't see why you couldn't use jet drive but getting enough motor (with a max weight of 800 lbs) to plane might be an issue. I am sure one of the houseboat builders on here will have an opinion.

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Bill

I told my wife we needed a three-car garage for my projects...she told me to ask her for permission next time before I buy a house.
http://www.unitybuild.net

If the motor is light I can offset it with ballast fuel or fresh water or even a raw water washdown tank to be used after trailering

Not too many months back there was an article in Wooden Boat magazine where a guy built a 30 foot lobster boat with a single jet propulsion. He simply cut up a Waverunner and installed it. I would think with SeaDoos, Jetskis, and Waverunners all having models that top 200 hp, you could get the thing on plane if that is the route you want to go. Weight would not be the issue, but there would be plenty of other issues to crop up.

Good Luck,

KB

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"I'm not trying to get it perfect. I'm trying to get it finished!"
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What other Issues could you forsee? the design lists optionc for inboard outboard v drive. How dose the power of the jet stack up to the shp listed? shp=x jhp? the studp plan lists
SHP Speed
52 SHP 14 knots
72 SHP 16 knots
94 SHP 18.5 knots
120 SHP 21 knots
150 SHP 23.5 knots
210 SHP 28 knots

And say I wanted the 120 shp option (midle of the road, not over powerd not underpowerd) what eng pump combo. Witch in your opinion is the most reliable? Im not compleatle un-familiar with the operations of things. but please explane as if i was 3 I will get a better grip. or is it better to find a 200hp and not push the throttle? ("better to have and not need. Then need and not have."):?

A jet is only about 2/3's as efficient as a regular prop (whether you are talking inboard, I/O or outboard.

So if you are looking for the equivalent of 120 SHP's produced by a prop from a Jet, you would need 180-200 BHP at the crank on your jet drives powerplant (where the prop driven would need 130 or less).

You also have to factor in that a jet will consume 30-40% more fuel than a prop drive to obtain the same "on water" performance.

Placing a jet on a boat that isn't going to run in super shallow water is kinda like using a 1 ton, 4 wheel drive to carry home a single bag of groceries on a well maintained city street.

Ya, it works and it may even look cool all jacked up and covered in chrome, but a little 4 cylinder compact does the job just as well and costs a whole lot less to run.

Gas sure has dropped in price since last summer, but really, why burn significantly more gas than you need to unless you will be running in shallows all the time...

Personally, I would be leary about adapting a jet ski motor. These are very low displacement engines cranking out gross amounts of horsepower - not bad if it's pushing along a couple hundred pounds of fiberglass and a single rider - but even with that limited amount of stress the majority of 5 or 6 year old jet ski's have had at least one engine rebuild.

There is no replacement for displacement if you want the motor to last longer than a couple of years...

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Graham

Yes, Plywood is "real" wood

A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it

T.Y. i feel i need to drop that idea. i belive ill go outboard or a single deisel something I can get the prop out of the way and out of swimmers reach.

As I pointed out, when you NEED a jet I think they are a great thing that allow you to boat where you couldn't without it.

And yes, they are really "cool" etc etc and even if you are undertaking a project "just because or just to see how it will work" then I would never try to talk you out of it.

But I just wanted to point out the drawbacks. Yes, they are absolutely necessary on a jet ski. Could you imagine if riders, who fall off with regularity started getting chewed up by a prop = not good for business

On other applications outside of Flats boats and river runners they just aren't a great choice in terms of either performance (in comparison) or operating costs.

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Graham

Yes, Plywood is "real" wood

A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it

Jets, or at least the majority of the USA built pumps don't like garbage or dirty water. their shallow advantages are in the lack of hardware under the hull, and mechanical simplicity. THere are economy losses, it is more like 10-20% in added fuel usage. There are some real advantages in dead-pull thrust, nimble high speed handling, stopping and holeshot acceleration. None of which is all that important in a houseboat.

IMNHO the biggest disadvantage would be the utterly miserable low speed handling, with that much weight forward of the center of thrust. It would really be akin to riding a garbage can lid down a ski slope. You would strike fear in the hearts of anyone standing on the dock... we are thinking the sheer terror kind of fear, not the run-of-the-mill dock shaker. Add a nice stiff breeze to confound the whole mess, and you would hate it. Don't do it.

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Some plan to stroll through Saint Peter's Gates, I plan to go through them at 150mph... backwards... in a screaming ball of flame, with a glimmer belt wrapped around my head, and a NOx button in my hand.

Lost,

This is from someone that KNOWS what he's talking about when it comes to jets.

I forgot about the low speed maneuverability(or lack there of)

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Don't Dream Your Life, Live Your Dream

Sry for the delay I dont get a connection wille out at sea. I just finnished the last hitch and I am home. The mail delivers 6 days a week, through rain sleet and snow. But tugboats are allways pushing it in and pulling it out.

I do belive that a outboard or even a pair will be more realistic. I found 2 2006 wave runners with busted hulls and a crippeld rider (shatterd leg) for $100 on a trailer they collided with each other and sank at the boat ramp I helped retreave thelm and left the guy my # he called after surgery to fix the leg. "I will be patient." I told him "I would waite till the painkillers ware off to make the purchase." But his girlfrend won't toutch thelm she got off unhurt but the fear has gripped her I am sure that the guy will sell thelm. The doctor said it will be a yaer befor he can walk muchless ride the runner. (He ran right up the stern of her rider. Shattering the hulls and sinking thelm to the handlebars.) missing her by inches. I jumped in and swam him to the shore and drug the rinners to the bank one at a time. Ruined the fishing for about an houer but then the fish came back. Got 2 4# flounders and 1 red @ 26" good eating fed the 4 man crew on the tug.