Homemade Jet Unit Build, Part 4, 6.5hp 212cc Test
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- čas přidán 22. 05. 2021
- The jet unit I build gets tested again with a different engine , a 212cc 6.5hp honda clone 4 stroke, also testing in a different river we haven't tried.
Thanks Cristo for filming check out Fazy Luck / @fazyluck
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Big fan from Australia. I didn’t think it would be possible to make a complete jet unit from scratch. Hats off to you boys. Can’t wait for you to fine tune it and for us to see the end result!
I’m happy the jet unit works I think with some fine tuning it will be good as you say. Thanks mate
Number 1 kiwi engineer who actually knows what he is doing, great job Daniel
This gave me hope after seeing jet boat prices like cleetus’s jet boat
Check out Mercury jet drives they use an outboard powerhead to drive a jet pump way cheaper than buying a Jet Ski just for the motor an there's lots of cheap boat haul options put it in
Jet boats are pretty expensive and need alot of power, my latest build might solve this and have a test video out soon
@@DktheWelder That's why I built one too. Way to expensive. I made a 15' Alumacraft into a "jet john" by installing two 300 gpm water pumps. It's a beast.
@@greenlizardusa3105 hey I watched you channel that is really cool ! And I think that your correct jet needs to be above water line , no body else seems to think so
Lol, try my scarab 215ho...
I was absolutely impressed with what u did with 6 hp ! It looks like a nine would run perfect .
Gotta get that jet more in the water. U probably know that already though. U could do it like jet skis and have adjustable output.
Very cool build, by the way, is the water you test in safe? I grew up near the Everglades in Florida, you don't swim there unless you're really sure of the area. That being said, Florida has nothing on Australian waters. Are there crocs where you live?
I’m in New Zealand, there is nothing dangerous in the water, well in the sea there are a few sharks
Bloody cool either way nice work
Get a snow mobile motor with the torque converter and all, would be insanely fast , especially with a 2 stroke triple or inline 2
Great job guys I think run bloody brilliant .
You will find the sweet spot
Thanks 👍
you deserve an award. I don't say that casually. well done Captain. friends bring beer, sandwiches, girls, gas...yours gets water wings.
Oh yeah this one is awesome. You look like a legend in it.
thanks 👍
Awesome!
It's partly to do with the shape of the Impeller and the nozzle is leaking basically acting as a brake
Yes, hopefully these problems are fixed in the latest video
There's nothing like a quiet little boat ride, eh ? :)
Clone engines can be worked for past 20 hp. I had a stock appearing 6.5 hp clone that dynode 33 hp With a stock up here in carb on Alcohol. If you throw mukini carburetor on it, there’s people have broken 35+ hp with these engines.
That’s crazy! How much power can you make and keep it reliable and able to run all day? What mods would take one to about 15hp?
35 hp out of a 212cc is sick af my mini bike has a Tillotson 212 with 13.5 hp and that shit is sketch what’s the best hp mod for these ?
Really cool, I have something very similar that I've been working on, however mine is radio controlled.
When the Zombies apocalypse happens ( the book of the Revelation) if I get stuck here I want you on my team
It's weirder than you think
czcams.com/video/fDBCgShR5Dk/video.html
Well done, I want to do that, maybe as said, jet nozzle in/under the water ? refine, play an try.
You should put the outlet nozzle below the water level, this way you will get more thrust. also run your exhaust hose down into the water as well. {will help with the noise}
There is always a debate about this most people say it must exit above the water line. But the exhaust should be underwater to stop the noise 👍
A huge leap forward in the development of the jet boat was the change to the nozzle outlet being above the water line. It’s in the book about bill Hamilton inventing the jet boat.
Add some plastic between the impeller and wall. Maybe PVC pipe. That will stop metal to metal contact and it will be replaceable.
I was thinking of pvc for the impeller housing also so rocks don’t jam it and easy to replace if worn
Awesome effort , nothing ever gets built perfect 1st time round , improvements are always avaiible , they just have to be thought of 1st
You have to test out certain things for yourself to learn I guess. Hopefully my newest one will work!
@@DktheWelder to me its a little ripper in production , the proto type lets say , best of luck look forward to seeing the modifications ,, just wonder if you made jet part reach deeper into water would this prevent cavitation when you bring revs up
Think the tires were dragging in the water a lot.
I think the sprocket idea would work great. You'd be able to fine tune it between torque and top speed.
Yes and I have a 13hp Honda clone motor I want to try ! I am thinking about what you said about putting the exhaust into the intake but can’t find any pictures or anything, I think the exhaust going in there would make it cavitation? I want it to be more quiet
@@DktheWelder ⁰
That's actually pretty cool
Route the exhaust so it goes under water like a normal boat. Less noise.
i am doing that in the latest video👍
You got to run the exsaust into the water so it wont make that mutch nois, i did that with my brighs and tratton build in the end
Instead of direct drive with the 4 cycle you should add 2 sprockets and a chain for a 1:2 drive. (Larger on engine) and add a centrifugal clutch so at idle you have no power to the jet drive
you need to drop the output down further to where the flow is actually pushing the boat
A few people have said that , it will be something I try next time👍
@@DktheWelder Sweet boat build! Jet outlet should be above the waterline. czcams.com/video/HgQTKWpNgQQ/video.html
Yeah couldnt agree with this more, you're effectively pointing a fire hose into the air because the lip of the stern, if you drop the nozzle into the water your thrush will have water to push against giving you heaps more efficiency
I don't think that's how it works. the thrust comes from accelerating the water out the nozzle, and if the nozzle is submerged it has to work harder to push water out. plus, you're dragging the nozzle thru the water. Also, jet skis and jet boats all have the nozzle above the bottom of the hull. there's probably a reason for that
I have the estuary behind my house goes all the way to sea. Feel free to bring it round for a rip some time, get some drone footage and what not
Also have a mercury tower of power if you want it. Needs wiring done cause it perished, all the colours are still there though.
that would be cool! I need to get it working better first
@@DktheWelderBrilliant video - I love it mate! Gearing should resolve it. Have you considered scavenging off an old jet ski?
@@tjrpmw yes those JetSki based boats are pretty common here in New Zealand, I just want something smaller
Just an fyi, those predator 6.5 hp motor (Honda clones) can be built above 20 hp. I know of a local go kart racer who bored it out among other upgrades and dynoed it at 23.7 hp with 21.3 ft/lbs of torque. Needless to say, until he wrecked his first time out from the build, he was in first place, he is healing up before he gives it another go on the track.
That is crazy power for a motor like that, I started looking into it and yeah the power gains are great ! But starts getting expensive as I get more money I think building one of those motors would be awesome!
buy kuaga 21 fit 150 hp jetboard
How size a prop ? And how to break ?
Bruce L has a good idea for ratio's or a scooter cvt could work as well 🤔 and a muffler would shut it up That motor didn't sound like it was running to well lol the wheels are a good add on maybe a spring bolt instead of a normal bolt and get rid of the factory carb and put a motorcycle carb on it🤔 getting there just a little more test and tune😊good luck bro👍
Thanks, that motor is pretty far gone haha. I have a 13hp motor I can use too but will definitely need to gear it up , a cvt would be great!
@@DktheWelder Can get a gokart racing CVT transmission on eBay for a few hundred if I recall correctly
Jet drive (any propeller drive really) is done properly when the engine is just below bogging down from the load 👌😁 that torque in the 4stroke will let you run a much bigger impeller😁
In the next video I tried a 13hp motor geared up but it didn’t work and it was heavy. I’m going to try something different next but will get back to the jet unit one day
came to comment this same thing. geared too short. engine hits max rpm no sweat.
A 4 hp outboard on that boat would push you about that fast. U r doing ok with that power. If you can get to 10 Hp it would b a complete different story. With 1 person you would definitely plane. 15 hp would plane two adults I recon. Keep going u r doing good keep it as light at u can 👍👍
I had a 3.5hp outboard and it went pretty fast with one person, I had a 6.5hp longtail on it and it planned two people easy , that jet unit isn’t very efficient. I will build another one some day
Just shows what a little extra power can do maybe twin engines 😃 great project keep it up 👍
buyvwharc13c2 6,5 jet outbard
Mate being a boat bloke In the UK people would prob take um to sea There great mate Well done
Awesome job!
Thanks👍
mate subd thats brilliant i built mine outa corri and fibre glass got a 6 hp outboard on it n apehangers hehe bloody fun things aint they i use it for prospecting down west here in tasmania looking forward to checking out some of ya vids bro cheers
Thanks! The ape hangers sound great!
@@DktheWelder the hangers r sweet for standing up to get off and for getting a better view of whats under ya to just watched a heap if ya vids good to see im not the only one making cool stuff out of crap goodonya man cheers
angle jet into water for discharge , its a start
Ok 👍
You should use a "love-joy" coupler to connect your engines to whatever your hooking them too...look it up...it's made so that the motor and "pump" don't have to be 100 percent inline
Universal joint coupler
Nice build. if u want, maybe try it with a predator 670.
That would be awesome! I have a 13hp i could try
Awsome. Ill be doing something similar. Very soon. Your build reminds me of my quadracycle build in many ways. I dont show the build tho, just the drives on my channel ♡ it
Sounds cool I will check it out
we need more fazyluck DK videos!
Good team aye!
I'd say you are losing a lot of power by having the end pipe only half immersed.
👀
Definitely taking inspiration from your fabrication techniques and skills..
Not sure how much the efficiency of the propeller is influenced by the fact that most likely the blades and the housing around them are not in the ideal relationship, I e. It spins freely with no gaps between the blades and the housing...
But man, it works! 👍
Thank was woundering if that would work
You know you can upgrade the carb and the engine to improve speed and hp
IT is possible to get that engine up to 10HP and a lot more RPM's (5500 to 6000 RPM range. Stock is around 3800 RPM).
you will need
heavier valve springs.
Carb rejetting or a new carb
Governor removal
A billet flywheel
A billet connection rod
Considering it is for a boat, I would not recommend hopping up the engine, because that many RPM's for a long time can destroy the engine. In short bursts is another story.
Thankyou! the motor will be held at full throttle for long periods of time so don't want it to blow up i want to start getting parts soon👍
@@DktheWelder those engines are meant for WOT all the time they were desighned for that
Thinks a 3 cylinder 2stroke in a 1 man sprint jet boat would be sick fun
That could be a future build , I would use a JetSki engine and pump
Check out cars and cameras. They build every variation of the 212
why do you have a jet boat with a jet that sits out the water?
Yeah I think there is a reason the guys that build these mini aluminum jet boats use crazy high horsepower 215h 300hp engines in the little jet boats, first takes a lot to get them moving also you want those high speeds to get it up on plane and allow it to ride in those shallow waters. I've never seen anyone else build their jet drive from scratch like you did and I think that amazing. Just keep tinkering making adjustments and definitely way more horsepower and you will get it.
It seems like they need a lot of power to move ! I am building a surface drive at the moment so will try that , I will come back to the jet unit once I know what to do
big hp jet fijetbyaght oñly not kigh sall bíta oicñboe 2 375 hp jetvir2 440 hp jets 37 fíitbyàgt v12400bounde drjghv40 moh topßpeed
Get ya like a v twin motor maybe out a old bike and try that in it it prob be perfect
I still have to be able to carry it, a 2 stroke dirt bike motor would be great
@@DktheWelder ohh maybe look for a Honda 150r four stroke engine off a dirt bike those
Are peppy maybe get ya the performance your looking for good videos though man take care and god bless
You absolutely can get more than 20HP out of one of those motors. A friend of mine routinely rebuilds them for go-kart racing here in the states.
o cool which is the best website to get parts from?
@@DktheWelder gopowersports dot com has the hotrod parts for these engines. They also sell engines complete as stage 1-3 with just crazy output.
The stock flywheel can fail catastrophically at high RPM so the governor is needed but if you swap in a billet flywheel and rod, a better carb and exhaust, you can get 6000rpm out of that thing.
@@DktheWelder go power sports
@@DktheWelder do not do it. Leave these 100% stock. The company I bought my long tail mud motor from told me these blow up sll the time when people tamper with em for boats. Terrible idea.
@@LRO1986 the difference between boats and go karts is boats are nonstop at full throttle and really loaded up. I think a few mods are ok but a 20hp would die pretty quickly I think
Yall could do so many upgrades to that motor make it make up to 25 hp
that would be great , I'm going to start looking for parts need more power for the latest version of this boat , video out soon
buyvsçoutv145 hyberrç25 hp jet oútvard
Dump the exhaust under the waterline like an outboard to quiet it down a bit.
yes! i try that on the next build and the test video is out soon
The jet boat stuff is cool and all but a open propellor out the back will give you more performance per horsepower I’d imagine not sure how it work but seems like the only advantage of having a jet would be shallow turning you’d have to have a rudder with a fixed prop out the back idk just thinking out loud on here .
Good job on building the water jet assembly by hand though that was awesome.
You are exactly right, I made what you are talking about check out the other videos on my channel
thats great true eye opener
Thanks ! It has been a great learning experience
Great video man maybe just get a outboard and put a jack Plante on it and just raise it cos it flew with the 3.5
Yes definitely an outboard is better than a jet . I’m just doing a jet unit for the cool factor and the cool way they manoeuvre. I will make another hull section with like a tunnel and a jacking plate and like an 8hp motor then it will really fly!
@@DktheWelder hahaha hell yeah but it might brake it a 5 or one like your old one would be good but if you want to go fast with two people 8 would be sick! Keen to see the vid make sure you reinforce it!
Your set drive needs be in the water lol
From what I understand jet pumps need huge rpm up or 30k to run well
That is a lot! Jet skis only do about 7k rpm
@@DktheWelder welll then aprentley I am rong
....
Have only played with rc units
40mm and under they all run 25-30k😅🤣🤣🤣
@@samgreer5976 yeah I see some of those Rc jet units do crazy rpm , my newest jet unit and motor setup might fi around 12k rpm but I will have to figure out the best impeller pitch. Did you make your rc jet units?
@@DktheWelder not yet looking to print some bigger ones but for my canoe
@@DktheWelder I have been working on an electric jetboard for a while. Hope my findings regarding the pump help. Smaller pumps around 80mm need around 12-15k rpm depending on impeller pitch of course. At 10k rpm I used the gas equivalent of 7hp for 80lbs of thrust (not enough for a board let alone a boat). I know the manufactured boards use around double that power. The bigger the pump the less rpm are required due to cavitation and efficiencies. Now since you are running gas engine you can't over amp draw the motor and melt everything, you should experiment on progressively more aggressively pitched impellers. Each one requires more torque but will push more water and with a larger pump you won't need such crazy high rpms
Definitely more gearing/rpm and a healthier motor. But it did well for the maybe 5hp and under powered jet it had. Would it be so difficult to simply rebuild that motor for better performance rather than swapping out a different one? Or would the 2t have better power output and higher rpm also plus some gearing increase?
What's happening with this boat Daniel?
Oh I see you switched to surface drive. Shame the jet couldn't work.
The surface drive was way faster, I am making a jet surfboard now
Very Cool !!
I thought the jet output was meant to be more in the water?
Well done..
thanks
Dude I'm building the exact same thing smaller 3 piece 7hp 4stroke Honda clone will fit in a hatchback
Do they Rev the same?
,you should of used slide pins with the cotter pin so u can just take off
Yeeeee
Need a gear box to spin the jet faster
at first I thought your pitch was off on your prop because you said this thing sucked and it was slow, didn't take me long to realize, 6 horsepower at 3,600 RPM, versus 20 plus horsepower, at up to 14,000 RPM. why do you think they use those two strokes in those jet skis for so long, the power to weight ratio can't be beat and the RPM is exactly what's needed for a jet pump. the bottom line: as long as you built the intake grate somewhat correct, you should have used that two-stroke it would have hauled ass. when you switched to that straight-in board, take a look at the pitch on that prop you used. your jet pump was a high torque, needed high RPM to get that thing rolling. the prop on the four stroke was very coarse and just two blades, it wasn't much of a screw at all. that jet pump was a straight torque screw that requires a lot of RPM.
The 2 stroke was way better more torque and rpm . But that motor was super un reliable and was sick of fiddling with it, that’s the only reason I went to the 4 stroke. I have a plan to remake the jet unit and a different two stroke motor setup
@@DktheWelder Are you sure you have the nozzle and impeller to the optimal size and thread angle to push the water out at high velocity? It doesn't matter how good your motors torque and rpm is if you don't have it using the energy efficiently or even at all!!
Don't forget that if the water isn't being pushed out at high speeds then no matter how much your pumping it is literally impossible for the vehicle to go as fast as or faster than the velocity of the water being pushed out! You might want to test making the nozzle smaller.
@@trevorthieme5157 I try a smaller nozzle in the next video I think . The pump is just too small and not built right , it is difficult to find any measurements, rpm, specifications , so it is kind of trial and error
Make the boat wider so it sits higher up in the water. Go on ebay and get a used Jetski drive.
Those boats are very popular here in New Zealand. But then you need a boat ramp or low river bank to launch it, also don’t want to make the same thing as everyone else haha
The jet drive was a move the water line instead of below it
saan ba tayo makabili ng pump drive
That’s bad ass
to all the comments about submerging the nozzle: I don't think that's how it works. the thrust comes from accelerating the water out the nozzle, and if the nozzle is submerged it has to work harder to push water out. plus, you're dragging the nozzle thru the water. Also, jet skis and jet boats all have the nozzle above the bottom of the hull. there's probably a reason for that.
Discuss.
Yes ! That is right I honestly got tired of replying to people saying it needs to be underwater
@@DktheWelder i just came across your channel, so a little late to the party. Props for building an entire jet pump from scratch! as you seem to have figured out, they are a complicated little piece. 3D printing is a cool idea for low power applications, and of course stealing the pump from a jet ski works great. there's a lot of room for improvement with your original pump. clearance between the impeller and pump housing is critical, somewhere around 0.25mm I think is typical. if you can get in there with a dremel to smooth out all the welds, radius the edges on the stator vanes, etc. just like porting heads, anything to smooth out the flow path will help. keep it up. you make some cool stuff!
Australia rules the waves
What is the diameter of your outlet pipe and propeller?
100mm for impeller, outlet 50mm
@@DktheWelder I think you try to make the pipe diameter bigger
can u make jet boat used engine 15hp or 20-25hp
Yes I had about a 15hp engine and it worked ok , I just wanted to see if this would work
You think this jet pump could power the flyboard? Of course the engine should be a lot bigger
It would I think, but a prop would be much better
@@DktheWelder Do you mean a regular boat prop?
@@May_Flower3 yeah jet pumps are really inefficient they are just for shallow water really and they are really manoeuvrable but need heaps of power to run
Dead Kenedies logo?
Yes! Hopefully it is different enough that it’s not a problem
You need America's craftsman lawnmower engine 14 hp single cylinder that would scream.
If you get an electric motor no noise and you could get more power and speed but making the right battery setup bit expensive
An electric setup would be great but like you say the batteries are beyond my budget 👍
@@DktheWelder Might find a salvaged motor and battery pack cheap if you're lucky. Not sure how easy it would be setting up with BMS etc..
What pump did you use?
I made the pump
Tune up the motor to more rpm!
why not use scrap parts from a dead jet ski?
heaps of people do that they work really well but im more interested in trying something different
It looks like if the height or pitch of the jet was lowered it might help also changing the hull shape should get it to plane alot easier but thats alot easier said than done when you already have the boat built. I honestly think the coolest thing would be to tweak the power on the motor along with your sprocket idea, those hondas do really make good power with some performance parts, same with the predator 212s plenty of predator 212s dyno'd at 20-22 hp but thats with piston, cam, carb, exhaust, ported head.
The hull is actually pretty fast with the longtail surface drive it went 25kph with two of us and that same motor. I have one of those 13hp 420cc motors I might put that in and today I tried a different nozzle. Hopefully I get it going fast by next weekend and get a video up
@@DktheWelder I agree that lowering the nozzle down more into the water should help you get more thrust, it seems and almost sounds like the impeller is slapping the water around instead of pushing it. Really cool build though! I've been thinking about making a similar motor but trying to make it portable to use on inflatable rafts, not sure how it'll work out though.
@@Pariah421 you might be right. I have put a 13hp motor in it and geared it up with chain and sprocket, which would also let me drop the whole jet unit lower . I will hopefully test this setup on the weekend and should get the next video out on the progress
@@DktheWelder Right on! I’m sure the bigger engine’s going to help you going faster either way too, stoked to see it.
small boat brother
I’d sub but i could see your toes in the shop, a big no no. Surprised your boss doesn’t make you were closed toed shoes for insurance purposes.
Thanks for the comment. My boss is particularly fond of my toes! luckily for insurances purposes this was in my personal workshop so don't feel too bad about subbing!
Put the motor in front of you, you at the back, ya weight distribution is so off. Nevermind power to weight ratio
Yes! I did this in the latest video 👍
Bisa kah kirim jet nya ke kaltim🙏
no it doesn't work properly
Make it electric. Y can get like 2kg 25kw brushless motor for 300-400$.
That would be great! What about batteries and controller and stuff ? Would it be expensive?
@@DktheWelder Trampa VESC controller 100v/240A about 400$. If y are not using heavy lead acid batteries. Batteries may be expensive like 600$. For batteries y need to make some research. I my self would build battery bank from 26650 or 21700 cells. Y could use 3x22V Lipos too it is like 200$ each.
Aussie or kiwi ?
Kiwi
If you want it to be faster, the jet needs to be entirely submerged
RPM is too slow. Max RPM on a stock Honda 6 5 hp motor is like 8k. Gearing is going to make a huge difference .
152
kool lol
Needs a bigger pump.
yes!
More rpm bro. This engine have 4500rpm not enough. I think 8000rpm is ok
Yeah I tried gearing up another motor in the next video but didn’t work I think the jet unit is too small?
What if you used a motorcycle motor
Like a two stroke dirt bike motor would be great
Put your exhaust under water 😆
I try that in another video but didn’t work out too well
You need to test it in some water not a puddle