New, looking for help

I built a FEMA gasifier and it lights, but it burns too hot and no useable gas. Its is air tested, is there anything i can do to this to improve it. Would like to play with this before i build a good one


What is the restriction size? I’ve always been interested in making a lid with a single nozzle built into it for a FEMA.

Also what was your desired engine to connect it to? Personally I wouldn’t use a FEMA on any sort of engine but you could use it as a heating and cooking gas.

Also based on this picture, I don’t see any way that the gas is cooled, unless you have some sort of water cooling in one of the barrels?

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Hello Roy and a big welcome to the DOW.

There have been a lot of discussion on the fema and sorry to say not a lot of it positive.

If you will go to the top right hand side of this page and click on the magnifying glass icon and type in FEMA a huge amount of information will pop up .

Thanks and welcome again .


It is 9 inch diameter and 18 inches long. Was going to run my old farmall M tractor. About 40 hp and 260 cubes. Didnt know better before this build. Just found this sight. Thanks for the responses.

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Welcome Roy. You have a fair amount of work done there. You may simplify some and be able to still use it safely on your tractor by converting it to charcoal. At least you won’t be locking up your engine with tar.


To second Tom’s idea, one question.

Is this the lighting port or the location for the grate shaker?

If this is the lighting port you can adapt this to put in a nozzle, if it’s above the restriction area. You can then run a single nozzle downdraft, you would also want a sealing lid for the hopper. If you ran charcoal you would probably want water drip for the nozzle to keep it cool, or blend in woodchips or pellets with the charcoal. For water drip a good starting point is one drip per second.

You’d want the nozzle to protrude a little bit maybe 1/3rd of the way through the hopper since you have a reduction much smaller than the hopper, you could sleeve in a piece of pipe to achieve this without having to take out any of the current welding you’ve done.

By charcoal we mean lump charcoal made from wood, pretty easy to make. Then you’d want to crush it down in sizes between 1/8" to 3/4". You can do that using a shovel edge with the charcoal in a barrel or bucket and sift it through screens.

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Just for an example of my current charcoal gasifier, here’s how I built it. I could have used a 55 gallon drum but I was short on them and used two grease drums. But all I have is a nozzle going in, a grate to hold up the charcoal and let ashes sift out, and my gas exit. My nozzle is about 10 inches above the grate but I have more diameter for volume, your 9 inch diameter and 18 inches length restriction should be alright. I might add a lip to let ashes collect and that would give me a self repairing ash liner.

That is one of the 2 lighting ports. Just above the shaker grate. My fire tube is straight from the upper barrel which is 14 inches. The lid is sealable


Edit: sorry I misread, didn’t realize the lighting ports are at the grate.

You’d need to have the nozzles somewhere above the burn tube. You wouldn’t light it at the grate anymore but you could use them for breaking up any slag that occurs at the grate.

Do you mind taking a photo of the inside of the gasifier? If it’s empty that is. You don’t have to empty it out for me if it’s full

You could just weld in the nozzle into the hopper wall, maybe a few inches above the burn tube 1/3rd of the way in.

Welcome to the DOW, RoyG.

You have shown us the tractor as the intended gasifer loading system.
You have told us the system base you are trying to adapt to use.
And you’ve shown us what you’ve built so far.

Please send pictures of the wood fuel stocks you are trying to gasify.
Pictured in-the-raw before gasifying attempts.
Pictures of it after gasification attempts. Burnt changed.

You have not told us how you are sucking flow through the gasifier to match the engines loading. What are you using? It’s power source?
Maybe you are blowing pressure flowing your system? Yes? No?
The engine’s sucked flow “loads” the gasifier system creating the internal at specific points heat needed to drive the thermal-chemical changes for the best results.

Each system design was designed for specific purposes.
The Wayne Keith system to be able to fuel gas modern vehicles at modern expected working powers, and speeds. And made of common round steels stocks from the big tall steel roadside signs tubing stocks. Air and water well tanks. And the thicker of standard steel barrels. Using chunked up woods.
The Ben Peterson’s Book System was designed for fuel gas fueling of heavily loaded 500cc IC engines to lightly loaded 5,000cc IC engines. To be made of 100 pound capacity and smaller thicker steel propane bottles. Wood Chunked fueled. Or coarse form wood chips. Those wood chips to be screened out of all fines. No leaf’s, or conifer needles.
The MENS (Mother Earth News) gasifier was for 4 cylinder, 6-cylinder, even 8-cylinder engines. To be made of thicker hot water heaters, propane tanks, some cast iron., black iron piping. To be fueled only with chunked up wood.

The FEMA?? Designed to be made from hardware store pieces right down to metal garbage cans and thin-walled metal plumbing parts. No welding. Only low temperature brazing.
Supposed to be able to use homeowners yards chipper fuels.
So it is, what it is.
What it is: is a tantalizing lie.

Other systems out there for specific purposes. And narrow specialized wood based fuels.
Wood pellets.
Only screened chipped woody fuels.

More pictures please.

Steve Unruh


If it is too hot, and burning up all the gas, you have too much air, and you are burning not gasifying. :stuck_out_tongue: It is pretty common to have air leaks in welds and such and it doesn’t take much. Without any other information to go on, I would probably pressure test it.

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Leakage, or air penetrates all the way to the restrictive opening or grille - too large diameter of the hot zone, too short distance from the nozzles to the grille, …

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Your second picture shows that this is a very nice build and it’s obvious that you are a builder. Accepting suggestions from other members, you will be able to turn this into a good useable system after a few tweaks. As SteveU suggests, knowing the type of fuel you have available is key to gasifier design.


Hi all, New to the forum and looking forward to building a WK gasifier. In the process of scrounging materials and sucking up any info i can get my hands.
I have been going over the old topics trying to gain more understanding from those before me. I’m still waiting on my book…
I’ve glanced at my dads book, He is well on his way to starting his rack and just about ready to start fitting things together on the truck.

Anyway, my question is… reading the old post i.e. Wayne’s 95 Dakota, 318 project. a lot of the pictures (at the beginning of the thread) don’t show up or are blurry, is this the same for everyone, are they corrupted ? or is there something wrong with the way my browser is displaying the pages?

Chris, it’s the same for everyone. It’s a roulette for any of the images posted before 2018 from what I’ve gathered. Not sure if they got corrupted in the server or what. Maybe something in the HTML changed?

If you want a really good look I would follow @Norman89 thread for his Chevota.


OK, Thanks :+1: :+1:

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Check out the Wilbur Smith build for the fire tube updates, I copied these on my last build and also I’ll have a video ASAP on the fire tube section with the updates on the premium side


Thanks Chris Weber .

Checking to see what happen to the old pictures .


My chunks were normal on top, smoked in the middle and burnt on bottom. Think they might be too big, around 2 inch cubes give or take. My blower was from a 1964 boat and it quit so i was using my shop vac to suck. Could it be too much air volume?


Does your shop vac have a CFM rating? I’d compare that against the CFM of the desired RPM from the intended engine.

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