Jet Boat VS. I/O

[petrey10]

I was wondering what you guys consider to be better and why a jet boat or inboard/outboard. Don't know much about boats so I thought I would just ask the experts.

 

[Zero Balance]

Re: Jet Boat VS. I/O

Well, they can both do different things. For instance My lil tin flatbottom has a 50 hp Merc OB jet on it and it'll cruise the small I mean real small rivers and lakes. I like the jet in this instance because it'll practically run on a wet floor. I only drft 3 to 4" on plane and can go just about anywhere. It's a 4x4 for water.

Another thing about a jet. you loose 25% of the horsepower when going from a prop to a jet. The biggest plus, you dont have to worry bout nothin less it's stickin outa the water.

Now a deep V I/O will take me out to much deeper water, give me a softer dyer ride and most likely much more peace of mind.

Dont get me wrong there are some jet boats that will do everything you need to do, oh another thing, Jets dont like weeds! But then again props dont like logs I rocks....

You'll have a cuddy or open bow to provide shelter, comfort or more seating and room for toys. or fishing gear....

 

[Silvertip]

Re: Jet Boat VS. I/O

With the I/O, you generally need universal joints in your fingers, wrists, elbows and shoulders to work on them. And nearly everything is done by feel since you can't see anything.

 

[dvan1901]

Re: Jet Boat VS. I/O

I/O's are generally easier to steer at lower speeds, but they now have fins that you can put on the jet of the jet drive (www.cobrajetsteering.com) which helps with this. In my opinion, there are a few things here. I believe that jet drive engine are easier to maintain; they are self draining so no worries about freezing in the winter, no outdrive to pull and maintain. They are similar to a normal engine, but because of the higher RPM's they run, the can be a bit finicky to adjust and tune. You can run a jet boat in shallower water, just need to be careful not to injest too large of objects in to the impeller. Lastly, no outdrive to worry about hitting, or hitting something with it. There is definately give and take, but I think the new jet drives have come a long way and can be better than a traditional I/O

 

[petrey10]

Re: Jet Boat VS. I/O

are jet boats good for skiing, wakeboarding, tubing? What are the top speeds like with these boats? What company makes the best jet boat?

 

[chaparral442]

Re: Jet Boat VS. I/O

if you plan on skiing, wake boarding etc-- I would choose an I/O-- jets are inefficient and you will burn lots of fuel with above activities. Actually- other than the "coolness" of a jet drive or the rare situations of needing shallow draft- there are not many reasons to buy a jet boat

If you want cool--just buy a boat with exposed exhaust

 

[dvan1901]

Re: Jet Boat VS. I/O

if you plan on skiing, wake boarding etc-- I would choose an I/O-- jets are inefficient and you will burn lots of fuel with above activities. Actually- other than the "coolness" of a jet drive or the rare situations of needing shallow draft- there are not many reasons to buy a jet boat

If you want cool--just buy a boat with exposed exhaust

Yamaha has made the number one seller for the last two years. I checked on performance tests and on the SX230 High Output model (twin 160HP) they (GoBoating) got the following;
"Our most efficient cruising speed was 29.6 mph, which will be good for a cruising range of about 171 miles." These engines are lighter than a standar I/O too so the boat can be lighter and gives you better hole shot. On this test, with two people and a half a tank of gas, they claim (and I've seen this same claim several times) that they got on plane in about 2 seconds and hit 30MPH in 5.5 seconds with a top speed of 51MPH. I've seen tons of these boats on our lakes and have seen tons of tubers and wakeboarders behind them.

 

[cmcpherson]

Re: Jet Boat VS. I/O

From everything I have read, Yamaha has solved almost all the old problems with their newer 4 stroke engines. The acceleration of a jet boat will never be beat by any I/O, never! I love the new Yamahas great layout, great quality, great price, hmmm... why don't I have one? Good question, better talk to the wife!

 

[chaparral442]

Re: Jet Boat VS. I/O

well sounds like you are sold on a jet drive. In the 70's when they powered jet drives with 455 CI engines--I salivated over them--they sounded great, looked great but in a top end race would loose to a comparable prop drive.

I can tell you there is a lot of discussion-- just query jet drive verus prop on google and you will get more information than you care to know. Only time will tell if the new jet drives can seize the prop driven market.

Most of us that have been boating for years will stay with props until proven jet designs prove themselves in the market place.

What ever you choose- it is a lot of money --make your choice wisely -in the end you will want to know that it was your decision.

 

[tic]

Re: Jet Boat VS. I/O

Why don't I have a jetboat?.. I seriously wanted one until I researched the fuel consumption... I was hot for the yamaha 23' HO... Let's see, two 160 HP motors running WOT to get 50mph... $150.00 worth of gas for a few hours of fun skiing on the lake is too pricey for me.. I believe boat tests will tell you 10.9 gallons per our consumption.. I've heard horror stories of almost DOUBLE that while towing skiers.... No thanks....

 

[Texasmark]

Re: Jet Boat VS. I/O

As others have mentioned, a jet drive for running up a river in a small boat is one thing. A jet boat with elevated exhausts on the 454 cu in engine is quite something else. About all they are good for is to buy fuel and cruise around the lake in the boat.....usually making lots of enemies.....some lakes outlaw them....the one I use does.

I/O a better choice in my opinion/experience, and a good OB even better.

Mark

 

[studlymandingo]

Re: Jet Boat VS. I/O

If you want cool--just buy a boat with exposed exhaust

And a set of earplugs for everyone on board​

 

[tmh]

Re: Jet Boat VS. I/O

The new Yamaha 230 IS a nice looking and layed out bowrider! Best at the boat show we went to.

Many old, biased opinions against jet boats still exist, many not very accurate. The new family bowriders are NOT the same beast as the older, rounder jet boats that were more of a big PWC.

One thing not mentioned here is that they can be a lot of FUN to drive! Sharper turns, spin outs, whatever. Heck, we're not all old foggies here, are we? Boating is about FUN, isn't it? I'd sacrifice some fuel efficiancy for more fun.

I would NOT, however, pick a jet boat if just cruising around in comfort was the primary use. Louder, less ability to trim into the best ride, etc.

 

[Texasmark]

Re: Jet Boat VS. I/O

I'm over 65. Check out my Avatar. I bought 3 props to get all I could get out of this critter. Do I fish much anymore? Nawwwww I spend most of my time racing around the lake.....staying away from others as a courtesy jesture....and there is essentially no wake. Old fogie? You figure it out. Grin

Seriously, on jets, my Merc service manual is for jet and prop engines. Since engines are prop rated nowadays, the comparison in the midrange engine is:

80 hp engine (prop rating) = 65 jet application
100 hp engine (prop rating) = 80 hp jet application

Course the boat mfgr can make up the difference in required hp (increasing your fuel economy) by building his boat for maximum efficiency (cut the weight, right hull design).

And I agree that the pleasure jets of today aren't anything like the ones I referred to.

Mark

 

[bjcsc]

Re: Jet Boat VS. I/O

As my boat is a jet drive, I'll offer the following:

Pros
Maintenance
There are very few parts to my drive. It requires no maintenance other than greasing the transom bearing and never has to be removed. No oil, no bellows, no u-joints, plastic impellers, etc.. The driveshaft is a straight shot from the coupler to the bowl bearing, on which the impeller is mounted. My engine is no different than an I/Os.

Draft
Requires very little water and is nearly impossible to ground.
Nothing hangs beneath the keel.

Safety
You can climb in and out of the boat with the engine running and there is nothing back there to cut you.

Wake
Compared to an outdrive, jets don't make much of a wake. I can stay on plane in areas where I/Os are at headway speed.

Maneuverability
I can turn on a dime.

Trim
No trimming necessary.

Cons
Fuel
It's not that you lose HP with a jet per se, but I do believe it requires more fuel for the same speed.

Wake
If you're a wakeboarder or trick skier you'll be disappointed. There is not much of a wake behind a jet.

Noise
I have through-transom exhaust (as do some I/Os) and it sounds like a muscle car (which I like). It's not excessively loud like a go fast, but it is considerably louder than an I/O with through-prop exhaust.


For me, the extra cost of fuel is a non-issue, esp. when compared to the outdrive maintenance/complexity.

I only have experience with my driveline. I have no idea if Yamaha or any other jet makers are similar.

 

[LTP]

Re: Jet Boat VS. I/O

What about maintaining steerage in a jet boat, don't you have to apply power when trying to turn, thats how some jet ski's are, you have no steerage without the engine running, and a litle throttle? i could be all wrong on this though? cause for some people that would be a big concern depending on where they are manuvering and what the boats main use is.

 

[bjcsc]

Re: Jet Boat VS. I/O

No, that's true. Although my jet has a rudder of sorts below the nozzle, I don't think it does anything. I do know that if I am at idle, say when approaching a dock, turning the wheel has no effect on my boat. But, I use this to my advantage. I head into the dock at an angle, spin the wheel hard, and a well-timed reverse thrust pulls my bow out and I end up parallel and next to the dock.

 

[NSBCraig]

Re: Jet Boat VS. I/O

Docking a jet boat can be a real pain in the butt and trying to explain to the marine patrol officer that you can't go that slow under the bridge he's sitting under cause the boat won't go straight at all when going as slow as he wants - not fun.

Sure are cool though.

 

[arboldt]

Re: Jet Boat VS. I/O

We've had a small jetboat for 5 years, and I'm thinking of selling it and going with a prop.

Unquestionably, it is a lot of fun. Previous posters have given a lot of the pros and cons, so I'll try to give other thoughts.

There is a huge difference between brands and ages. Mine's a 1995 Sea Rayder with a Merc Sport Jet 90 (avoid that engine like the plague). It's noisy, underpowered for the size of boat (13.5'), and high / awkward maintence. WOT and I can get up to 30 mph maybe. It sucks gas, and many times I've had to shut down the engine to dive under the boat and pull weeds out of the intake grate -- and I try to be very careful to avoid weeds, too. Something about Eurasian milfoil and invasive species in west Michigan lakes...

A neighbor has an '03 SeaDoo 15' Sportster (?). His is much quieter, faster, more fuel efficient, etc. I shoulda spent a bit more up front, and I'd be much happier. But even then it's got less power and speed than a comparable prop drive. His son has a bigger (18') jet boat / much bigger engine, and can tow several skiers / boarders / tubers. I can't pull even one adult, and the Sportster can pull small adults, but not anyone over 150#. BTW, a good skier cutting back & forth across you wake can pull you all over the place. An experienced driver can compensate, but it does require much more attention than a prop boat.

Idling in neutral, there is still a small amount of thrust. You're never truly in neutral. If I'm in neutral and checking something in the engine, I turn the wheel so I'll go in a small circle. However, that is small enough that you don't have steering control, so going up a river or channel that's slow / no wake is a challenge (see comments about removing weeds).

Hope this helps, although by now you've probably made your decision.

Al

 

[74glencoe]

Re: Jet Boat VS. I/O

I/O's are generally easier to steer at lower speeds, but they now have fins that you can put on the jet of the jet drive (www.cobrajetsteering.com) which helps with this. In my opinion, there are a few things here. I believe that jet drive engine are easier to maintain; they are self draining so no worries about freezing in the winter, no outdrive to pull and maintain. They are similar to a normal engine, but because of the higher RPM's they run, the can be a bit finicky to adjust and tune. You can run a jet boat in shallower water, just need to be careful not to injest too large of objects in to the impeller. Lastly, no outdrive to worry about hitting, or hitting something with it. There is definately give and take, but I think the new jet drives have come a long way and can be better than a traditional I/O

WHAT???[/SIZE] I can turn complete circles around any I/O on any day, I can go from full forward to full reverse at any engine speed, and stop my boat from 20mph to a dead stop in less than its own length. we slolom and double ski behind the boat often, we pull tubes all the time, plus my boat doesnt make a four foot deep wake so you can cut across the wake on a slolom ski at 30-40 mph without tearing your ***** open when you bite it. I have pulled a wakeboarder, and no you cant get ten feet of air without crossing one of the wakes of the water chopping I/Os that all you yuppies own!!!