General woodgas and carburetor question

Greetings Everyone,

I watched a video on YouTube by NightHawkInLight ( where he used carbon rods and and created an arc underwater and captured the gas produced to burn later. He said that the gas was basically a mixture of carbon monoxide and hydrogen. One of the comments was someone asking if you could indeed run an engine on this mixture. I replied to the comment/question by saying:

“This gas is a similar composition to woodgas. Woodgas has been used for a long time to fuel regular spark ignition internal combustion engines. All you would need is an adapter to mix the the gas with air and pipe the mixture into the carb/intake.”

Now I don’t know the exact composition of the gas being produced in the video, but I assumed that with hydrogen and CO, it should be workable in an engine.

Anyway, someone replied to my comment saying:

“You don’t have to premix with air as this is what the carburetor already does. When they do it that way its just because they were too lazy to drill a hole in the venturi of the carb to add the inlet for the wood gas.”

I was going to reply to this person because A) he called people like me lazy (since my gasifier is set up to mix the chargas and air ahead of the carb), and B). I think he is wrong in that I don’t think you can pipe enough woodgas in through a small hole in the venturi to reach a proper mixture with the air. I stopped my reply to come here and ask you all if it’s possible to do what this person says and actually get an engine to run reliably. I’m not sure I have ever seen anyone do that. I always assumed that the woodgas doesn’t have enough energy density to achieve a correct stoichiometric mixture if piped in through a small hole in the venturi. Am I wrong?




I believe the mixture is 50/50 or close to it, so…that would be an equal size hole venturi as air entry, which wouldn’t work as a venturi, more of just a turbulent air flow? I don’t think that would be possible within the carburetor, not even for a lean idle

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Тhe fact that you were answered is indeed so, you can make the engine work in this way, but in this case, the carburetor enrichment flap should become an air regulation flap. Another nuance - the hole in the carburetor diffuser should not be so small. I did this and with a 21 mm diffuser diameter, the wood gas pipe was 18 mm (these are the inner diameters). The whole system worked, but still required manual adjustment of the gas / air ratio, I did not achieve the result as in carburetor systems with propane. This is due to the great resistance of the gas generator and the constantly changing calorific value of the gas.


I was designing a venturi style woodgas mixer a while back, similar to Tones automixer. Will try and find old skeches. But like Joni sayd, the hole shuld be so big it becomes unpractical to modify a existing carb. Zero bennefit.

Im preety sure the guy that replyed never run a engine on woodgas. I think he never even came close to a gasifier…

The setup Nighthawk is having will produce a mixture of 50% CO and 50% H2 and trace amounts of hidrocarbons. No nitrogen! Extremely potent gas but unfortunaly its practicaly preety useless. Efficiancy is low and most importantly, the carbon that forms CO comes from the rods so they will consume fast.

Practicaly this is only usefull for lab purposes, like if someone wuld fiddle with Fischer-Tropsch.


I think you are more right than he is. :grin:


Thanks guys. My assessment was pretty close. Yes it can be done, but it probably doesn’t work well enough to make it worth doing.

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For me, the problem would be having one hand on the steering wheel, and having to decide whether to use the other hand to keep the arc going or in my normal mode of operation give all the idiots on the road with me the finger.


I would sure like to see the energy calculation on that. Probably 1000 watts in = 0.1 watts out. Yes a curiosity only. much worse than F-T. Almost junk science if he did not include this data. :thinking:
I used to have an old fashioned carbon arc light for making stencils for screen printing. That thing was a beast. 240vac 30 amp circuit. Weighed a couple hundred pounds. Cool to use, a little scary at times!!

This is the closest picture I could find quick.
It looked similar to this. This picture may not be of a carbon arc light, it is too clean!! same manufacturer.
Arc lamp - Wikipedia


I played around with that type gasifier, a long time ago. Remember it was a bit difficult to keep the arc. One rod was carbon and the other was a bundle of TIG tungsten. It might have a place in certain waste disposal. For us, I do not see a use unless it is to waste time.


I agree the process shown in the video seems to be high risk (and energy consumption) for little reward. Having that much “excess electricity” doesn’t seem plausible in many cases.

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Funny this should pop up a week after i got my parcel of carbon rods , and i am just in the process of learning how to weld battery busbars and terminals back together on failed deep cycle lead acid cells that come onto the scrap yard , great fun , but this looks like it could make for interesting play time .
will have to see if the power from old scrap battery’s will work as well underwater as they do on top

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I like this NightHawk guy, but in the department of woodgas he has most things wrong. Per instance, the bee smoker gasifier he built… Thats not realy a gasifier. And runing that gas trugh any kinda engine… Flashbacks from my youth return when l flooded a 50cc 2 stroke with about a cup of tar :smile:


I have left a comment saying he should try a charcoal gasifier for that little 50cc engine.

He would probably need a larger rear sprocket though to make up for power loss. They’re only 2hp stock to begin with.

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It sounds to me like that individual does not understand internal combustion engines very well. There is a big difference between a carburetor using gasoline or other liquid fuel as opposed to one using a gaseous fuel which wood gas is.

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