jet drive or i/o

[ripler]

What's everyones opinion on jet drive versus i/o, what are some of the pros and cons of a jet drive. I'm kind of leaning toward a Seadoo and the jet drives is my only concern.

EDIT Sorry I did a forum search and didn't find anything, I was doing a google search and I found a thread here asking the same question.

 

[H20Rat]

Re: jet drive or i/o

http://forums.iboats.com/showthread.php?t=394690
http://forums.iboats.com/showthread.php?t=340472

Read those two threads... Take the anti-jet comments with a grain of salt, most of those people haven't owned a modern jet drive of any sort and are going on second hand knowledge at best.

Seadoo has being doing jet drives a long time and have a very good system down. Their style of drive has changed very little, and is somewhat common between the boats and PWC's.

You can sum it up like this... 90% of the people that have owned jet drives love them. The biggest drawback isn't even what most people will convince you of, fuel usage, its actually weeds. If you live in an area that has lots of weeds, jets can be a pain. (especially one without a cleanout mechanism)

 

[45Auto]

Re: jet drive or i/o

Read all the tests and reviews, look at the actual test data. Drive or ride in a friend's if you can.

Pretty much at least 90% of the people who've owned any particular type of boat love it.

 

[ripler]

Re: jet drive or i/o

Read all the tests and reviews, look at the actual test data. Drive or ride in a friend's if you can.

Pretty much at least 90% of the people who've owned any particular type of boat love it.

Thanks for the links. I'm heading down to Deep Creek Lake this weekend to test drive a Seadoo I used to have a i/o so I do have something to compare it too.

 

[breastman569]

Re: jet drive or i/o

What are you planning on doing with it? if you using if for a runabout type boat they are great, if more skiing or wakeboarding they can be a pain. smokingcrater said it best, the only draw back is weeds, i have owned both my last jet was a yamaha and it was fun but out here after a big weekend they lake is just trashed and i was always sucking somthing up most of the time garbage, also if you boat in shallow waters you need to know how to navigate around sand, other than they very smooth and fast running boats. Good luck!

 

[Thajeffski]

Re: jet drive or i/o

Dont care what you guys say, they use a LOT more fuel then an I/O even when the motors are comparable.

 

[H20Rat]

Re: jet drive or i/o

Dont care what you guys say, they use a LOT more fuel then an I/O even when the motors are comparable.

which jets have you owned?

At least for the jets i've owned, they are VERY similar in fuel consumption to their prop equivilents.

I've had 5 jet power craft, 95hp, 120hp, 130hp (2), and 175hp. All were 2 strokes, and all had VERY similar consumption compared to a 2 stroke outboard of similar year. Yes, if you compare a 2 stroke jet to a modern 4 stroke outboard, there is going to be a difference.

For the record, i've also owned somewhere north of 10 different outboard powered craft, as well as 5 jet powered, so i've got experience on both sides of the fence. Answer my first question on which jets you have owned and then compare them...


Anyway, in case anyone is wondering about actual facts instead of hearsay... My current jet boat, 17 feet LOA and powered by a merc 175hp 2 stroke, and will consume 20 gallons per hour at WOT. It will also do around 55 mph.

Lets compare that to a random similar I/O. Larson 180 with a 190 hp I/O. It goes slightly slower (49.7 mph) and consumes 18.1 gph. Both boats are rated for 6 people. So a nearly 10 year old 2 stroke compared to a 3 year old 4 stroke I/O, and there is only about a 10% difference in economy... Not too bad in my book!


http://www.boattest.com/boats/Boat_video.aspx?ID=1199#Test-Result
http://www.boattest.com/boats/test_results_PrintP-e-oem.aspx?id=46

 

[Thajeffski]

Re: jet drive or i/o

I've personally owned 2 jetskis (one two stroke, one four stroke) and 2 small jet boats. And then there's my bayliner I/O

The bayliner uses so much less gas it's crazy. Now of course it uses less gas then the dual engine boats, but it even uses less gas then both my jetskis!

One jetski only had 2 cylinders!! ( 98 951 Seadoo and a 4stroke Honda).

Now yes I do take into consideration that the skis are usually going high rpms....so that does have something to do with it.

However, that's exactly WHY a jet propelled boat uses more gas. It requires MORE energy IN to produce the same amount of force going forward.

I myself would love a 20 ft+ jetboat. Just be aware that your average RPM will be higher in one then in an I/O and that's where the extra fuel goes.

 

[H20Rat]

Re: jet drive or i/o

I've personally owned 2 jetskis (one two stroke, one four stroke) and 2 small jet boats. And then there's my bayliner I/O

The bayliner uses so much less gas it's crazy. Now of course it uses less gas then the dual engine boats, but it even uses less gas then both my jetskis!

See above tests from boattest... Same capacity boats, and only 10% difference in fuel. and that was compaing a 2 stroke vs 4 stroke. Using the actual test results, there isn't much difference.

so... what makes up the difference. People tend to drive jet boats alot harder. If you drive hard all the time, then of course they are going to drink fuel.

 

[ripler]

Re: jet drive or i/o

ll be using it for kneeboarding, skiing, tubing, etc. I will also be using it on the river, I had a i/o boat before and there were plenty of times I hit a unseen object and wondered if the outdrive was still attached to the boat.

 

[cwhite6]

Re: jet drive or i/o

Look at the following link and the comparisons on it. The newer modern jet boats Yamaha is making are very comparable and in many cases shown better fuel efficiency at cruising speeds. Now, if you fly around all day at full throttle, yep the gas will kill ya. Also, the OP is comparing i/o and jet. To me that means something like a Yamaha or Seadoo jet boat, not a jet outboard.
http://www.yamaha-motor.com/boat/boatcomparison/boatcomparison_page01.aspx

 

[Thajeffski]

Re: jet drive or i/o

Toss in the maintenace requirement of an I/O and the fuel cost difference becomes meaningless.

Do you own jetskis or boats?

Every year 4 stroke jetboats/skis require new oil. Sometimes twice a year if they are super/turbo charged.

Then, they need to have their jet pumps re greased at least once a season.

Now, if you happen to suck something up and you screw it up.....not only do they need new impellers, but 9/10 they need a whole new tunnel thing around the impeller. (I forget what it's called).

2 strokes need new plugs every few weeks!

 

[hubbard53]

Re: jet drive or i/o

Do you own jetskis or boats?

Every year 4 stroke jetboats/skis require new oil. Sometimes twice a year if they are super/turbo charged.

Then, they need to have their jet pumps re greased at least once a season.

Now, if you happen to suck something up and you screw it up.....not only do they need new impellers, but 9/10 they need a whole new tunnel thing around the impeller. (I forget what it's called).

2 strokes need new plugs every few weeks!

sir, your information is outdated or something.... it simply isnt true.

I own a yamaha jet boat and absoutely love it. I've suck ONE thing up one... a bunch of grapes (yea i know, weird) - I know immediately due to cavitation. Shut down, pulled the cleanout port, removed the grape stems, and went on my way.

Fuel use is equal on modern jet drives/engines - there are lots of comparative studies if you look for them