View Full Version : Jet Drive Vs IO

12-24-2005, 04:40 PM
I am thinking about purchasing a newer bowrider. I am considering a jet Drive. I have had I/O's for years .
What are the pros and cons of each?

12-24-2005, 04:43 PM
Jets are not efficient. They are useful in areas of shallow water and dead heads.

12-25-2005, 07:48 AM
There's also no prop to chop up bodies--important to some people.


Merry Christmas!

12-25-2005, 11:51 AM
Anything before an I/O.

12-26-2005, 11:25 AM
"The jet drive has no way of effectivly muffeling the exhaust noise. They handle very poorly at low speeds and reverse is worse that a single screw I/B with a 7" rudder, not to mention sparkys painful fact.

I/Os are less expensive to purchase and operate, although you should expect more in maintenance costs over time.

If you water ski at all, don't consider the jet, for obvious reasons.

Good luck

12-26-2005, 06:49 PM

Maybe if you look up (critically) at the following page and follow the links, you will get a clearer idea of the pros:
http://www.ultradynamics.com/ ("")

My personal experience was gathered some years ago in southern Chile, carrying fishermen upriver on a 19' flat bottom boat powered by a 70HP Evinrude Outboard that had a jet propulsion turbine instead of a propeller.

It was great for shallow waters with rocks and pebbles as a bottom, and jumping small rapids was big fun. The one we had was about 25% less fuel efficient than a prop engine of the same horsepower.

I understand that today versions have overcomed some of the efficiency problems of the older ones but in any case I'm afraid you will get less efficiency specially at low speeds."

old guy
12-28-2005, 08:57 AM
"I thought the only reasons for a jet were:
operate in shallows
throw rooster tails to raise shallow self image.

I one I've used were about half as powerful as conventional rigs on the top end.

In Alaska they are the best for river operation, do to rocks and shallows. They climb thru shallows to the above pools and then can travel fast to the next bar. You can get 50-100 miles up river comparied to a conventional boat. this is great if you hunt or fish. The conversions on 50 and 80 hp outboards seem to be very durable.

I drove a Berkley on a 454 chevy block, complete with NO2. 5 foot beam. loud as hel and fast. No real boating purpose for that machine....what we call a 5 minute boat. Run it for 5 minutes and put it back on the lift.

They can suck bottom materials into the rotor, even at slow speed $$$$.

If I fished or hunted along shallow rivers, I'd definitely consider the jet drive. Especially the outboards with an electric motor jack.


Keith Olivier
03-19-2006, 11:19 PM
"My 10c. The biggest difference is that jet boats lack a fin in the water. Very poor low speed control. Easy to spin if you back off the power in a turn. When crossing waves bigger than just 1 or 2 feet, the boat is inclined to skid up the slope on one side and then skid in the opposite direction down the other side. This behaviour doesn't feel safe at all.

The advantages regarding shallow water etc can be misleading. If you actually run your boat in shallow water, ingestion of rocks and sand off the bottom will have you replacing the impeller and wear ring very fast, once it wears to the point where you are overreving the engine and sucking fuel without much forward motion.

And marine growth can be a curse, particularly nead launching sites in national / state parks. You no sooner get in the water, than you have to go over the side to pull weed out the intake.

I'm though with jets. Thy are better off on PWC for which you don't need expect reliable transportation..