Drawbacks of Jet Boats?

[Expidia]

Seems they are moving up from being a glorified jets ski.

I have a friend who owns a house on a lake with like 125 frontage and a long aluminum dock going out but his problem is most of the bay he is in is like 1 foot deep.

So he is thinking of buying a Jet boat. One that's big like a deck boat style for his family of 6 to go on. I've seen a few around lately that looked real nice. I don't see many reviews on newer models though.

Anyone know what the drawbacks to them are?
What about it sucking up sand like a jet ski might since his dock is in such shallow water?

Another thing I read in a thread here is that they tend to have bad gas mileage if you are not at planing speed?
I think they would like to cruise around at lower speeds, but have enough speed to get from place to place too.

A search here using the term Jet boat or "jet boat" just pulls up a lot of threads with the word boat in them.

 

[jjohnson120]

Re: Drawbacks of Jet Boats?

When I think of jet boat I think of the old school ones with huge motors and blowers that fit maybe 4 people, are super rough unless on water that is like glass, and not practical for anything than occasionally going fast when it's not white capping. You may be referring to the Yamaha and Sea-Doo boats that usually have twin motors setup like jet ski's. These I don't know much about.

 

[QC]

Re: Drawbacks of Jet Boats?

Fuel efficiency is the main drawback, and also that steering requires throttle. I have driven them some, and they can be a ton of fun. Big blocks and jets were very popular here 20 years ago, and still are on some parts of the Colorado River. The newer jets are mainly from SeaDoo and Yamaha. Twins to match what you are asking for in most cases. They use high RPM, small displacement engines which also hurts fuel efficiency. They are very high quality machines though. Also, jets do not have transmissions, so maintenance can be very good. Sand ingestion is not a great thing, but they are somewhat tolerant.

 

[oldjeep]

Re: Drawbacks of Jet Boats?

Jetboat will suck stuff off the bottom in 3 feet of water washing out the drive, impeller and wear ring. Might be able to get around that with stainless screw and ring. If you boat anywhere there are weeds near the surface then forget about a jet, nothing like having to dive under the boat to clean all the weeds out of the grate.

 

[acarter92]

Re: Drawbacks of Jet Boats?

Well, I've owned jet skis and know someone with a jet outboard. All I can say is $$$$$. As if regular boats aren't bad enough on fuel, I think it's something like 25% less efficient. But, they are fun.

Austin

 

[Expidia]

Re: Drawbacks of Jet Boats?

Thanks for the comments so far. I always thought of them as like twin seating jet skis. But two weeks ago when I was closing up my rig after a day on the lake one was parked next to me in the lot. I had to look at it twice because it looked like a brand new Cobalt style boat, but when I looked at the drive Imwas surprised to see it was twin jet drives.

I was not really interested in jet boats that day, so I didn't check out the make of the rig.
Who makes an expensive jet boat as this one looked like at least a $30,000 rig?

 

[QC]

Re: Drawbacks of Jet Boats?

Yamaha and SeaDoo.

 

[Scott Danforth]

Re: Drawbacks of Jet Boats?

sucking up a bungee chord or section of anchor rope will take out the impeller. then again, so will sucking up a few rocks. the fuel economy is one thing, however a jetboat is insured like a jet ski. a $30000 jet ski. that alone was enough for me to cancel my seadoo speedster order a few years back.

 

[H20Rat]

Re: Drawbacks of Jet Boats?

so i've owned 4 different jet boats, (and countless prop boats) and about the first thing I can say, is unless someone as owned a modern jet boat, ignore their advice. Although possibly well intended, its based on what they have heard, which may or may not be true...

Fuel efficiency: modern jets are very, very similar to a similar prop boat. In fact, if you spend most of your time driving fast, a jet will get often get substantially better mileage. There was a recent thread comparing a jet boat to a wake boat, at WOT the jet was substantially better! Yes, at idle and less than plane speeds, jets suck... They aren't meant for trolling!

Sand... I boat in water that is often inches deep. I've done this for years, without a single problem with sucking up sand. A jet will NOT suck things into the impeller from 3 feet down. yes, jets don't like rocks, much like a prop boat doesn't, but sand isn't a problem. (I've also run my jetboat into water that was just a little too shallow, no damage!)

Handling... A jet boat will EASILY out handle a single screw prop boat. Not even a comparison. I really need to make a video before the summer is over, but here is my normal docking routing. I pull straight into a double wide floating slip. Once i'm in the dead center, I stop, then rotate 180 degrees to face out. At that point, I modulate throttle, steering, and the reverse bucket to get side thrust, and slide myself straight to the side, and tie up. There only comparable boat that isn't a jet that could do that is a twin screw with pods (keep in mind this is with a single engine jet)

Weeds... Ok, can't say much on that one. Jets don't like weeds or sucking up rope. Some have cleanout grates, and some are just a pain. i've never had to dive to clean mine, the worst I've had to do is cut power and float for a couple seconds. If you suck up a rope with a jet, it will ruin your day.

 

[rallyart]

Re: Drawbacks of Jet Boats?

The best selling 23' boat for a few years has been the Yamaha so there must be quite a few people who enjoy the newer jets. They are a good all around boat.

 

[smclear]

Re: Drawbacks of Jet Boats?

so i've owned 4 different jet boats, (and countless prop boats) and about the first thing I can say, is unless someone as owned a modern jet boat, ignore their advice. Although possibly well intended, its based on what they have heard, which may or may not be true...

Fuel efficiency: modern jets are very, very similar to a similar prop boat. In fact, if you spend most of your time driving fast, a jet will get often get substantially better mileage. There was a recent thread comparing a jet boat to a wake boat, at WOT the jet was substantially better! Yes, at idle and less than plane speeds, jets suck... They aren't meant for trolling!

Sand... I boat in water that is often inches deep. I've done this for years, without a single problem with sucking up sand. A jet will NOT suck things into the impeller from 3 feet down. yes, jets don't like rocks, much like a prop boat doesn't, but sand isn't a problem. (I've also run my jetboat into water that was just a little too shallow, no damage!)

Handling... A jet boat will EASILY out handle a single screw prop boat. Not even a comparison. I really need to make a video before the summer is over, but here is my normal docking routing. I pull straight into a double wide floating slip. Once i'm in the dead center, I stop, then rotate 180 degrees to face out. At that point, I modulate throttle, steering, and the reverse bucket to get side thrust, and slide myself straight to the side, and tie up. There only comparable boat that isn't a jet that could do that is a twin screw with pods (keep in mind this is with a single engine jet)

Weeds... Ok, can't say much on that one. Jets don't like weeds or sucking up rope. Some have cleanout grates, and some are just a pain. i've never had to dive to clean mine, the worst I've had to do is cut power and float for a couple seconds. If you suck up a rope with a jet, it will ruin your day.

100% Spot on.

I've had my little jet for 5-6 years now and have never had any issues with sand or rocks. With the exception of this year, weeds have never been an issue. But, the lake is ~1.5 feet low this year.

Handles better than anything, but does require a learning curve.

Fuel efficiency is OK. It is much more efficient than my speedboat. But, my speedboat has a 440 in it and sucks ~12 gallons/hour if run hard. Compared to the pontoon, it's a hog. I consider it kind of a wash.

 

[Expidia]

Re: Drawbacks of Jet Boats?

Thanks, I appreciate those positive views also especially from owners of jet boats. My friend though is not interested in those small one step up from a jet ski type boat. He's more interested in the runabout type rig.

Could posters also post a pic of their jet boat rig, so we can see what the boat they are commenting on looks like? It would really help in weighing out the various opinions.

 

[oldjeep]

Re: Drawbacks of Jet Boats?

so i've owned 4 different jet boats, (and countless prop boats) and about the first thing I can say, is unless someone as owned a modern jet boat, ignore their advice. Although possibly well intended, its based on what they have heard, which may or may not be true...

Fuel efficiency: modern jets are very, very similar to a similar prop boat. In fact, if you spend most of your time driving fast, a jet will get often get substantially better mileage. There was a recent thread comparing a jet boat to a wake boat, at WOT the jet was substantially better! Yes, at idle and less than plane speeds, jets suck... They aren't meant for trolling!

Sand... I boat in water that is often inches deep. I've done this for years, without a single problem with sucking up sand. A jet will NOT suck things into the impeller from 3 feet down. yes, jets don't like rocks, much like a prop boat doesn't, but sand isn't a problem. (I've also run my jetboat into water that was just a little too shallow, no damage!)

Handling... A jet boat will EASILY out handle a single screw prop boat. Not even a comparison. I really need to make a video before the summer is over, but here is my normal docking routing. I pull straight into a double wide floating slip. Once i'm in the dead center, I stop, then rotate 180 degrees to face out. At that point, I modulate throttle, steering, and the reverse bucket to get side thrust, and slide myself straight to the side, and tie up. There only comparable boat that isn't a jet that could do that is a twin screw with pods (keep in mind this is with a single engine jet)

Weeds... Ok, can't say much on that one. Jets don't like weeds or sucking up rope. Some have cleanout grates, and some are just a pain. i've never had to dive to clean mine, the worst I've had to do is cut power and float for a couple seconds. If you suck up a rope with a jet, it will ruin your day.

Sounds like you have been lucky - my friend who owns a twin engine 21ft seadoo has not been as lucky. Just google seadoo challenger impeller damage and see how many people have issues with sucking bottom through the drive and wiping out the non SS impellers. My RXP has the same engine/drive that they put in the smaller boats and it is capable of picking stuff off the bottom in several feet of water, which is why the reverse gate exploded one day when someone decided to power reverse near the shorestation in 2ft of water.

We've also had a 454 powered jet with a berkely drive - OK way more powerfull than the jetski boats that they sell now.

 

[emoney]

Re: Drawbacks of Jet Boats?

I just sold my jetboat and I, too, would disagree about some of the "horror stories" that are out there as it pertains to fuel consumption and reliability. No different than any boat in those regards, in my opinion. The only "drawback", and even that is more adaptation and adjustment, is slow speed steering is horrible, unless you modify the factory set-ups. I've driven both a single and dual engine set-up, to include the new "power assist" from Yamaha, and for me, if you don't add some of the new, after-market deflectors there's a fairly long learning curve.
Only picture I still have saved, so sorry;

Having a stainless steel impellar is a good thing if you spend any time near grass. Living on the Continental Shelf (Gulf of Mexico) and the grass flats, I can say with certainty that it paid for itself almost every trip out. I never once had to go diving to unclog the impeller, but I was probably lucky.

Given a choice, I still prefer my outboard, but, if I had to always contend with a foot or water or less, I'd go back to a jet boat in a heartbeat knowing what I know now. Wish him luck from me!

 

[QC]

Re: Drawbacks of Jet Boats?

The fuel efficiency issue is real. Just check boattest . com It may be more than 30% in some cases. With that said, fuel is not the reason to shy from a jet. If a jet fits your needs, then get the jet. I would run one in a heartbeat if I was back down on the lower sections of the Colorado.

Edit: I take the fuel thing partially back. The Yammies are pretty good. The Sea Doos are horrible. Go figure.

 

[gtochris]

Re: Drawbacks of Jet Boats?

Something I dont see mentioned is that they loose more HP through drivetrain then a prop- 150HP Outboard has more "prop" power then a 150HP Jet.

 

[Jlawsen]

Re: Drawbacks of Jet Boats?

so i've owned 4 different jet boats, (and countless prop boats) and about the first thing I can say, is unless someone as owned a modern jet boat, ignore their advice. Although possibly well intended, its based on what they have heard, which may or may not be true...

A Hamilton 212 Turbine is nearly 90% efficient and will blow just about anything through it without damage. The drawback, if there is one, is that the cleanout is inside the boat unlike a 12JC where it's outside. It's not a big problem but I've cursed it at least once.

However, to the best of my knowledge, there isn't a deckboat out there that will draft less than a foot when loaded. You need deeper water to get up on plane and then you can run through short periods of shallow water without a lot of problems.

 

[QC]

Re: Drawbacks of Jet Boats?

Yeah, I think someone mentioned below. But single V8 jets like I was used to (with the 12JC) are a lot different than these "production" boats from Yammie and SeaDoo. The latter using very high RPM (11K) and twins in some applications. Very different animals. Also, there is a wide range of efficiency of the pump itself, and then there is efficiency of the combo of a jet and specific hulls. Very hard to generalize, even though I did as well.

I thought the 12JC cleanout was inside?

 

[Jlawsen]

Re: Drawbacks of Jet Boats?

My bad, it is.

 

[haulnazz15]

Re: Drawbacks of Jet Boats?

I thought the 12JC cleanout was inside?

I'm pretty sure it is inside. Cap hold on with two wingnuts.

In any case, the new jet boats are nothing like the BBC/BBF units of the 70's. The newer models from SeaDoo and Yamaha are more fuel efficient than the old ones, however the efficiency is still 10% or more lower than an I/O or outboard. The twin engine setups do make maneuvering in tight quarters easier, but the low-speed tracking of the jet boats is much worse than an I/O. It's not that you can't maneuver them, it's that it requires a lot more finessing of the forward/reverse bucket to keep it in check.

I don't think I'd want to run one in a foot of water (I sure won't run my jetski in a foot of water), but at idle, 2' of water might be doable, especially if the bottom is heavier rock. I think the layouts of the new Yamaha are some of the best around for a runabout, but it's pretty close to a lot of other runabouts out there. The new jet boats are nice, but definitely not for me personally. The problem with a foot of water is that many runabouts (jet or not) will draft more than that in the hull alone.