Compressed Air Go-Kart Engine 

By using the intake valve as the exhaust you have also given the air the path of least resistance to get out of the motor which allows the engine to run more efficiently than if you had simply forced air down the intake. Great job.

Actually it is the opposite, with say 100psi of air feeding it, the little 2 horse Briggs has so much toque that you can hardly stop the shaft when squeezing it as hadr as you can wearing a leather welding glove! I believe it is due to the air continuing to come into the cylinder while the piston is descending, while a gasoline engine starts losing combustion pressure as soon as the piston starts to move down. This thing tops out at about 1100 rpm (but it is in effect a 2 stroke)

Thanks, I actually built this thing 12 years ago, but that was before my vid camera days! Then I tore the compressed air motor off, and put on a gasoline 5 horse, the kids had a great time on it, I swear we must have put 300 miles on it over the years!

awesome job...look forward to your mods to extend its range.

I have filled the head with JB, but you have to be careful not to block off the flow from the valves to the cylinder, if you get too carried away. Yes, putting an "O" ring or something around the valve stem would help reduce wastage into the crankcase!

Sorry to say, it only makes the loop down the driveway, onto the road and back. About 10 years ago I had a similar setup on the same gokart, with a 10 gallon air tank, it seemed to have better range, but still only a few hundred feet. The gokart gained a bunch of weight with the roll cage, so that doesn't help now. A lighter weight vehicle say with 3 bicycle tires may do a lot better, I am sure engine efficiency can be increased also.

Yes, I bet that would extend the range, possibly even make it continue moving slowly until I shut the gas engine down. It is amazing how much energy is lost compressing the air, mainly in the form of rejected heat thru the compressor.

I hadn't thought of it that way :) This thing still could use lots of work, I want more range out of it, I am building a larger motor, hoping it will power the cart at lower pressures.

Hope it helps out, I did a lot of step by step developement on this type of engine a few years ago, that how I found out about the nasty valve seat leaks. These engines don't make any heat, so that helps out a lot in choices of materials to use. I also remove the oil ring since I run grease on the crankshaft. I am not sure what the best oil is, since the engine doesn't get hot.

Yes, one wheel drive does save tire wear on pavement, and it doesn`t handle very badly, it wants to pull a bit on gravel, but will still swerve around fine. I haven`t thought of using steam, mainly just because of the danger. But a fellow youtuber has sucessfully ran a steam powered Briggs this size, so I have thought of doing it. I just have so many projects on the go that I haven`t tried out steam yet.

Yes, that is true. posi can be a tricky thing to handle sometimes though, easy to loose it with too much power and not enough tire!

Are you using a plastic camshaft? If so. I would roughen the surface up, maybe even drill a few shallow holes, anything to help the JB grip it. I had a similar problem with the plastic starter gear on my electric start 4 horse, it was missing 1 tooth. I JB'd up a new tooth, but it came off a short while later, plastic is hard to stick to!

It's sad how many people have so little knowledge of physics that they think the equivalent of perpetual motion will work. No, boys and girls, you can't run the exhaust of an air engine back to the tank. After the air gets out of the engine it doesn't have enough pressure to go back in the tank. And you can't boost the pressure back up with a mechanical compressor running off the engine, because that would rob all the power from the engine and not leave any for useful work.

Interesting idea, you may have just inspired me to make more FrankenBriggs engines! Thanks for the advice! I will subscribe to your channel, so it will send you the vids (if I make some new ones)

It's a side valve so make an new head from plate with a pocket over the valve. Air is fed into the pocket, the valve opens into the old exhaust port which is blocked off by a blanking plat with a tube which feeds the air to a hole drilled through the head over the piston Steam engine conversions were like this in the 1940's

Yes, my son sugeested a CO2 tank. It would extend the range quite a bit, and I may do something like that in the future. I didn't even have any oil in this engine, so it wouldn't live long on the grease oiling. I plan to use compressor oil in it, just a reduced qauntity. Yes, I think I will install a regulator, that would also help extend the range. I am making engine improvements right now :)

Another person said the same thing, that it ran backwards. I think I moved the cam timing 3 teeth one way, as I have a new timing mark on it. I think I ground the old exhaust lobe off, then welded the new double lobes on, so the one I put the air into now has all new lobes on the cam, timed to work this way.

I'm wondering how you made it run regular clockwise with the exhaust as the intake, did you change the cam timing? Mine runs backwards with the air going in the exhaust.

Interesting idea, Nitrogen, I hadn't thought of that! I think 250 psi is way too high, I would have a guyser of gas coming out the valve cover area, leaking by the valve guide! I think I will regulate it down to 80psi, so it doesn't pop the valve off the seat, and waste air. I am alos going to add some compressor oil to help lube the cylinder wall better, reducing friction.

I don't know, that is starting to sound like perpetual motion a bit! :) I do have something related in mind to try though, thanks for watching my crazy machines :)

now we just need an oxygen tank and regulator from a cutting torch

Charger you ever thought of using a SCBA tank my dad was a pro diver and he said the has like 2000 PSi in them and that was in the 80's and 90's I don't know how much It could be but with a regulator it could GE a rideable or more practical car great work man!

Just a wacko suggestion, could you drill a small hole, say 1/8" or less into the camshaft (the steel shaft part), and either tap threads into it, or screw in a wood or sheet metal screw, then cut the head off, leaving a shaft that the JB could surround. The steel would be fairly strong still I think. That is a tricky situation.

Oh, I had to monkey with the cam timing also, I know this one has a new set of timing marks on the cam. I would run a full speed cam, but I only have 1 crankcase cover modified for that, and I am planning to use it on another engine. Plus, with going to a model 10 engine, everything is out the window! Time to start over welding up another cam etc. Guess I also need to adapt the 1/2" pipe to 3/4" for the larger engine.

sweet thanks for you time.. nice basic build... but use a carbon fiber tank Incase of accident no schrappnal ;).. also maybe add in a small solar panel and air pump? + a oilless 1/4 inch tool oil tank. a spray gun or pressure sensitive control for the air control. then just use the handle for the master kill switch. add in a nice PMA or pmg design and generate even more power.. add magnets to your flywheel? and some coils to collect.. also some charge controllers for the solar and the magnetic generator. install some lights and better suspension. tire rims. a bloating body and maybe a jetski turbine for marine or sell it as a addon but make every vehicle float. add some ac maybe a small pelter module design or a separate compressor that can be activated with a electric clutch driving from a separate wheel or just the solar and electric storage. infred heating or just take the warmth from the DrLs hid cooling fins and the breaks also add in a system for regenerative breaking like the Prius. then go even further and add in devices you can ad on to manually charge or set and boost charging like a vertical wind turbine. and have people exercise... pump up your pressure. get fit stay healthy and save the planet.. one Hart car at a time ;) maybe even add in a HHO Generator feature to power the motor as well. let's just top all of that and make the wheels have frictionless bearings or use the pressure aquire in a turbine design and not with a combustion based crank design. turbines and window charging solar restoring. crypto mining Smart super car. Add in googles Android smart radio / phone.. wifi hotspot. Xfinity sponsorship with some hot wheels and even pimp my ride ;) and we got the best product available with quality and ethics always first. 60% of proceeds go to the needy to help those in need and wildlife preserve. 30% to the many future technology advancements and bolt on attachments and upgrades soon to be available once we start building the perfect and last needed ground transportation​. Eco Friendly. Community Neighbor Friend and Family Fund. Global Transportation Stability and Energy building assistance. Whole World​ Unity. The Hart Kart. #Lumen Dan J Hart

I will look into that, it would be nice to go furhter than 100 feet!!!! lol I am going to fasten a seccond 10 gallon tank on, so that should more than double the range. Plus I am building a longer stroke motor, that hopefully will use the air more efficiently, also extending the range. Lots of fun things to experiment with :)

In principle you are right, but a one wheel drive kart actually doesn't go too badly. This one came like this, so I have kept it that way.

man that cam sounds like its realy well ground but what i dont understand is every motor i have double lobed and put in the exsaust it runns bacwards i cant tell from the video ur look like its running the right way how did u get it to do that or am i just missing somthing (i got a little bolnd in me lol =3-

HeHe, you are being fooled by the camera! I saw that when I watched it on vid, the tire is actually turning counter clockwise, to drive the gokart forward. The camera shutter speed is messing the vid up. I cut off the inlet air early, while the exhaust air has pretty much the full stroke to expel the air. This engine will run backwards also, I just make sure the flywheel is positioned correctly for CCW rotation at the sprocket end. I am working on a model 10 (4 horse) motor, 2-1/8" stroke.

Super. А как отрегулировал клапана ?

interesting concept

hey i have not dropped the steam engine project instead i ran unto a snag, jb weld or quick steel wont work, it shears the lob. so got any other ideas?????? thanks

I got a Briggs Raptor 3 on the kart and i was wondering how many thousandths I can go bigger with the stock block. I do have an Arch aluminum rod on it,but every thing else is stock. Its not a lawn mower motor its a race motor without the governor. It is a five horse block but to my knowledge it is equivalent or maybe higher than an eight horse. thanks

Yes, I get a very limited supply from a 7 gallon air pig at 125psi :( I am working on that, folks have been giving me some good ideas :)

Really, yours uses more air than this! This is only a 6 cubic inch engine. I also welded new cam lobes on, and seriously reduced the height and duration of the intake air lobe ( I think the valve only lifts about 1/32 of an inch now). I time the outlet valve so that it is open for most of the piston stroke. Is it possible it is blowing the inlet air valve off the valve seat (I shimmed the spring also to make it stiffer) the valve seat in the block can also leak, JB Weld can cure that.

Question for you. Is there any reason you can't tap into the intake side now and use that to refill the air tank?

is there a way to trap the air coming out to feed it back into the motor?

Hello. Is this motor a gasoline motor and you decided to change it in an air-motor?

So could you in turn run this motor on an air compressor efficiently supplying compressed air back to the motor?

Im just wondering about oil if your compressing air into where the motor is supposed to exhaust then it would make the motor run backwards and wouldnt it create pressure the opposite way to pushing oil out or would it cycle oil the same as normal just in reverse without causing anything like pushing all the oil out the crank case breather hose and on the ground idk just asking how that would work

and i want so badly to finish this project! got a pulse jet maby and also a deltic, not burnt out just want it to run

Thats very neat

That tank will push the cart for about 50 feet. The cycle of any internal combustion engine is far too short to make good use of steam or compressed air. They utilize the speed of expanding combustion gasses to make power, and are optimized for that. To make power from compressed air or steam, you would want a very long stroke and a SLOWLY moving reciprocating assembly. OR you can use a turbine (like in a hand held air drill) but these require giant volumes of air. A piston driven long stroke turning the same speed of the wheels (or even slower) would work much better.

So it is a plastic cam causing you grief?

What if you re-use the (exhaust) air? Wouldn't that make it have Perpetual air? Well, not really perpetual, but significantly increase its range?

i never looked into co2 tanks whats there rating

You would probably be better off using a smaller motor like a 4-stroke whipper snipper because the smaller the cylinder the smaller volume of air needed to fill it each cycle. I don't know if it would have enough power to drive the go kart but it would defiantly use less air.

It's amazing when all you have to do is think of the possibilities... As well as question everything, such as the fans on turbos today. There small and completly insufficient when you look at them. Just putting a bigger fan on a turbo that is more efficient is going to make monster gains in power and boost. Especially at lower RPM's, where there is apparent lag?

I wonder if you could extend the range by using a solar panel to charge a battery, which then could power a small air compressor attached to the tank. It might be stop and go, but, you'd probably extend your range a bit and make the system somewhat self contained.

i could try that but one small problem charger the hole cam i plastic but the 2 ends the middle is all plastic (cheap)

I noticed you don't have any oil in the crankcase. Why would that be?

How far can you drive on a charge? 700 feet would be totally awesome!

If you ran this engine backwards would it work as an air compressor?

Is this motor overunity?

Yes, indeed it would be! Running an air compressor with a gas engine, using the air to power an compressed air engine driving another air compressor would be a total waste of energy! I don't know what the overall efficiency would be, but it is very low. There is just too much heat energy lost compressing the air. My 4 horse compressor hammers away for a few minutes to pump the tank to 125psi, then the air motor gobbles it in 20 seconds :( Put 4 horse motor on go-kart...much more fun :)

Where we can see a video of this go kart running?

yes i got holes and a rough surface, its sheered 2 bother were on not the same spots

How long will the engine run on one tank of air ? 1-minute??

how did u get it to run so fast and not use so much air? my air engine is a pig, help!!!!!!!!!!

use a mini ram air pump to pump a little bit of the waste back into the system!!!! if you got it efficient enough it would last longer by a few percent!

Have you thought about making it steam powered? if you did some research im sure you could do it safely.

HEY DUDE ,DID YOU DO ANYTHING TO THE PISTON RINGS ?

Why ?

thank u

You can use an impact wrench. Get another for posi!

Heat the air with the sun as it come out.

How would that variable valve timing help in this application?

Make the exhaust go back into the air tank and it will be infinite air since the air can only go one way but make sure the tank can only have air traveling one way from both ends basically meaning having air come into the air tank in one hole and out the other but it can only come in through that one and out the other

yea many commercial go karts have one wheel drive because with no differential they wouldnt turn as well and tires would wear out on pavement

bro...can that 7 gallon or 10 gallon tank powered air grinder...??? please reply...because i also have a project to make air powered scooter by using air grinder....do you think it can work??

very nice its agood project

Good question. Why Better question. Why the hell not!

hi, I was wondering if you could e-mail me some info on your set up with this engine. what is the psi your using to get the engine to work. also have you tried using the flywheel to turn a air pump so that it continues to pressurize the air tank as it's running. thank you.

What about using a impact tool with a gear reduction?

But won’t the piston and cylinder wall heat up because there is no more gas and oil to keep it cool

How to do exactly the same and what is the capacity of the motor??

Connect the engine to an air compressor and let the engine pump air and it goes through the cycle again and you get more run time

That wouidn't help, since the air is at very low pressure when it comes out.

i think perpetual motion is a bit more complicated than that.

Only problem with that on a Go-Kart is having enough air!

do you even need the flywheel??

if you did that to like a 4hp lawn mower engine and riged it up with a lawn tractor trans had a few air tanks you could have something

why don't you just put regular oil in it?

High pressure tanks and a regulator would increase range and available power.

10 yrs ago wow......

Why couldn't you capture the spent oxygen back into the tank from the exhaust in a closed loop to maintain supply and operating pressure then eliminating the need to refill?

I have this. It's called an air impact wrench.

you really should have used a centrifugal clutch on it

Wow be good it it recycled back into the tank with a one way check valve

Cool....

HaHaHa lol :) Yes, I do the same thing, figure I don't need something, so I get rid of it, then a month later, when they are ALL Extinct like the Wholly Mammouths, I despairately need one!!! I have stopped doing that with Briggs stuff, I Hord it all !!!! I have 158 Briggs engines in various states of disrepair!!! About 12 are running engines. I used to take them apart, and store the pieces, now I just leave them together, they take up less space that way!

Could cut the fins off the flywheel for a little less resistance

old video. sad how youtube has gotten so dull now, noone posts this fun stuff anymore... anyway... idea. you got compressed air. it lost all its heat when you compressed it. when its released, it expands, but it cools down, as it is absorbing heat from its surrounds so it CAN expand. if it was kept all nicely insulated you would basically be liquefying it (with a few stages of course...) as there would be no heat to absorb. now, you can compress air in stages... its much more efficient. and you can expand it in stages... also more efficient... then you dump the air. sigh. cold air. double sigh. moan. so.... multi cylinder. assume you can get 1000 psi or more in your tank, no silly 150 psi nonsense. from tank, into a heat exchanger. then, say a 30cc brushcutter as first stage. exhausts into a heat exchanger. feeds into a second cylinder, standard briggsy. expands again. back into another stage of heat exchanger, then finally... fed through a carb and into a third cylinder, still with a decent pressure behind it... where its combusted in a simple "twostroke" cycle, a lenoir type cycle with no compression as the gas is already compressed... and the exhaust is then dumped back through the heat exchangers.... heat the compressed air between stages using your waste exhaust heat to increase the amount of expansive work it can perform in the cylinder. every 249C you can get the air to is double the work it can perform.

Pointless, oh and congrats that you made your kart slower !

So now get a battery powered motor to fill the Air Tank !!

2 horse? My slash nitro makes 1.3 with a .20 cubic inch (3.3cc) but it's on an rc car

Why not just return the air back to the tank with a valve

Now just put a gas engine on it to drive the compressor instead of a air tank. Then you might go further than 50ft.

Can i make the same engine???and how??

you only have on driving wheel on your car unless you have posi.