Jet Boats.....

[James Clarke]

What Do y'all think about jet-boats? I like my outboards with propellers. Does anyone here have a boat that has jet propulsion? Tell us what ya think about em.

 

[ondarvr]

Re: Jet Boats.....

If ya need need one they're great, otherwise they are of little value. They are slower, louder, handle odd and use more (a lot more) fuel (we are talking outboards). I use mine all the time in the rivers around here, they're great in shallow water, but you give up a lot of things to get that benefit.

 

[dajohnson53]

Re: Jet Boats.....

You'll find that inboard jets (like Merc. Sport jet or a V6 or V8 engine with a modern jet pump) are getting pretty efficient nowadays.<br /><br />I've owned two boats with jet power. One, a Jetcraft with a Chevy 351 (5.7) "Kodiak" conversion and a jet pump. I liked the whole rig for operation, but the big V8 took up too much interior space, and the rig was two unforgiving in real shallow water (which is the reason to have a jet imho). This pump just was hard to clear of debris and the rig was too heavy to push off a bar. I didn't think the fuel efficiency was too horrible for the speed it would produce. It burned about 8 gph at 30 or so MPH - more than three MPG, which I think is good.<br /><br />I now have a larger hull with a big V6 Johnson outboard with an aftermarket jet lower unit. This thing is very inefficient when it comes to power and thus gas consumption. It loses, I think, about 25% or more in power. Therefore, for a given load and speed, you need to run the rpms higher. The gallons burned per hour for a given RPM stay the same, but you go 25% less far. I'm lucky to get 2 MPG with this rig. The advantages are: the outboard jet is really easy to work on, once you learn it. It is also easy to clear of debris when needed (again- this is why one has a jet in the first place, to push the envelope on depth, etc.). In my boat, it is much, much easier to steer at low speed compared to the inboard - could be hull, could be engine, but bottome line is it is easier to maneuver.<br /><br />In spite of the fuel issues, I prefer the outboard jet quite a bit for shallow water exploring. For more cruising in not so shallow water, the inboard would be my choice - faster, more comfortable, can be quite a bit quieter, and more efficient. The interior space is always an issue with an I/O or inboard - you just need to have a fairly long (>20 ft) and wide (>6 ft floor), imho, to make it work well.

 

[timmathis]

Re: Jet Boats.....

My son has a see doo jet boat and that thing will fly it is pretty good on fuel to. But it did not come cheap... I will stick with my outboards. Tim

 

[kenimpzoom]

Re: Jet Boats.....

I have had my Merc Sport Jet for several years and I dont think I can go back to props.<br /><br />I like to be able to cruise just about anywhere and not have to worry about hitting underwater objects.<br /><br />I fish in the bay where the water can be 1 ft deep in many places. No problem for me.<br /><br />In the Trinity river, with a prop boat you have to go a further mile past the outlet before you can turn west as it is very shallow. In my jet I just get on plane and skip in the 1 ft water and I am on the fish much faster.<br /><br />Ken

 

[Kanadakid]

Re: Jet Boats.....

JC,<br /><br />I'll tell you my impressions. First off I labored over the decision to guy a jet powered boat. At this point I feel I got the best of both worlds.<br /><br />I think the key (do not underestimate this) thing is to have it set up properly. There is a lot to this task. <br /><br />Dead-rise of the boat<br />Flat / no keel for the last food or so<br />weight balance<br />Enough HP<br /><br /><br />If you get one set up properly then you will have a craft that you will be pleased with.<br /><br />I am always amazed how shallow I can run in my jet. Literally inches. And on one occasion (don't try this at home folks) went over an exposed rock without hitting. <br /><br />Jet handle differently. They don't get the steering response you get with a prop but you get used to it.<br /><br />They will tend to slide a bit in turns, this is fun.<br /><br />Mine is a 4 stroke so its pretty quiet.<br /><br />It does not cavitation in rough water. I have been in some that do. Again if it is set up correctly it won't.<br /><br />When I'm on Canadian lakes I can't tell I have a jet.<br /><br />It is good on gas.<br /><br />You loose 30% of your power head HP rating at the jet pump, so yes you do have to buy bigger to get the speed you want. Mine WOT speed is 35.<br /><br />But I can basically go anywhere on the water.<br /><br />Funny story and it happens a lot. One of the lakes in Canada has a huge back bog that is great bass fishing. To get to it there is 1 mile of submerged stump fields.<br /><br />Well i normally will go wOT right through this long narrow field. I can see these bass boat guys just watching and although I can't hear them ......one look to the other and they are saying......watch this clown hit. But it never happens.<br /><br /><br />About 10 minutes later I can hear one of the in a 50K sparkly boat coming and then I hear it <br />moan down and turn around and go back. <br /><br />In all fairness to these guys I should put a jet boat sticker on the side. I don't wish anyone to bust up their boat while on vacation.<br /><br />But when I do this it inevitably bait one or two of them to try it.<br /><br />Weeds are not a problem if you stay at WOT. Otherwise you need about 3 ft of clean water to get started. once on plane you will be OK.<br /><br /><br />I hope this is helpful, All in all I'm very pleased with my jet. Most Bass boat guys want top end speed. I'd rather be able to get where they can't a little slower.<br /><br />Kid

 

[kenimpzoom]

Re: Jet Boats.....

Kid I agree 100%. I can go in my jet where others only dream of.<br /><br />I went across a 3ft wide shell reef with about 2 inches of water. Was going about 20 mph, saw the reef, cut power, made it over it, and then back on the throttle.<br /><br />That put me in a lake that was 2-3ft deep.<br /><br />I just can't believe there arent more small lake/bay boats out there that are jet. They like the tunnel hull/outboard boats here in the bay. Not a bad idea, but most I have seen have no freeboard making them useless in any type of waves.<br /><br />Ken

 

[CFronzek]

Re: Jet Boats.....

It seems some are talking about pump powered boats and some are talking about shrouded propellers. <br />For those that take their pump powered boats into the shallows; how do keep from sucking pump destroying junk off the bottom? <br />In the PWC forum on this site there was considerable chatter about what to do when a pump has swallowed a stone or two. The answer seemed to involve big money.

 

[Chief101]

Re: Jet Boats.....

Nobody has mentioned shrouded props yet. The grate on these jet pumps filters out the big stuff. Mine kicks out small stones all the time. Plant debris can plug up the grate, but anything that gets past that gets the boot. I tend to use my jet boat at least 90% of the time. No worries.

 

[Kanadakid]

Re: Jet Boats.....

In 3 years I have never sucked anything into my pump other than leaves and it turns them into dust in a milliesecond.<br /><br />When you are going 35 mph over a 6 inch geavel bar, the speed of the boat prevents anything from getting sucked up into the intake. <br /><br />However Chuck, if I were to try to start out in 12 inches of water and opened it up, yes I could probably suck up some gravel.<br /><br />What I do is use my electric to get me into 30 to 35 inches of water, then I am fine.<br /><br />Also remeber there are grates over the intake that prevents anything large for getting sicked in.<br /><br />I know it sounds unlikely but trust me, sucking in rocks n stuff really isn't a problem.<br /><br />Ken, a suggestions. When comming upon a shelf reef or another obstruction......if your going to go over it or can't turn back.....open up to WOT and ride it out. <br /><br />1) Your boat will ride higher at wOT and you will acutally feel the displacement and the boat lift up when you hit shallow water....similar to an airplane.<br /><br />If you hit keep ridig it out and don't throttle down. You'll do less damage and won't get stuck on the shelf. It will sound horrible, but your better off riding out.<br /><br />I can run it shallower that I can drift.<br /><br />Jetting is not for the weak of heart. <br /> <br /><br />Kid

 

[dajohnson53]

Re: Jet Boats.....

Debris can be an issue in a few ways.<br /><br />First, just pulling silt, sand, pebbles, sticks etc. through the pump (either outboard or i/o) will wear the pump impeller. Aluminum wears quicker than stainless. This is why you need to sharpen the impeller edges and, with an outboard, adjust the clearance on the wear ring. So that's normal wear and tear.<br /><br />Another issue is actually damaging the impeller - sucking rocks aand sticks rough can do that, although in my experience it's more of a question of heavy wear and tear vs. light. I've never seen a unit just get destroyed.<br /><br />The main thing that happens (again, either outboard jet or i/o)is that the grate gets clogged with debris - sticks or stones stuck in the grate impeding water flow - causing cavitation or loss of performance. It is a normal thing to have to stop to clear the grate, and experienced boaters have a variety of ways to do it. Simplest is just shut off the engine and stop the suction and the stuff drops off. You might have to get at the grate and physically clear the debris- pull out weeds or sticks or pry the stones out. With an I/O that can be difficult to get to - and I STRONGLY recommend a "stomp grate" for an I/O jet boat. Sometimes, once in a blue moon (but it happened to me!) a particular size and shape of stone can actually lodge in between fins of the impeller causing problems and you actually have to try to get at it and pry it out or break it (the stone).<br /><br />All this stuff is very minor, not really much different than the wear and tear and prop clearing issues you experience with prop boats. Actually less, because you will never experience the catastrophic prop breakage you can with a prop hitting bottom and breaking. A jet pump just doesn't hit the bottom - the pump is higher than the bottom of the boat, the grate is on the bottom approximately.