MP's Charcoal Gasified 1995 F150

MP95F150CharcoalGasifier.pdf (355.1 KB)
Hey folks, Mr. Wayne, Chris:
I emailed Bruce Southerland last August, told him that after a long hiatus, I was going to resume work on a charcoal gasifier for my 1995 (“OBD 1”) F150, shortbed, 5 speed, 4.9 L straight six. Well, that was 7 months ago … maybe this time is for real.
At Bruce’s suggestion, been reading Ryder, Kristijen, Bobmac regarding the fluted nozzles y’all created/utilized. Think that is the way I want to go!
Excuse my rough drawing, above. Thought about re-drawing it, but anyway, here it is.
Going to slope the nozzles a bit, drip water into each nozzle. Two nozzles, 1 1/2 " Sch 80 pipe, unless I should go larger. Going to put a baffle in to slope the charcoal to them, also will have a little “bird house roof” (tip of the hat to Maxgasman Thanks!) Going to try to make them pipe union integrated removable Don Mannes style, as Steve Unruh might put it.
Couple of questions, numbered on the crude drawing:
1.)Diameter of each nozzle hole?
2.)Number of nozzle holes?
3.)How close to the side to have the first nozzle hole?
4.)How far below the flutes to place the bottom drilled 2 " outlet pipe?
5.)How much space below the below the outlet pipe to the bottom of the gasifier, ie ash space?

Also, how far apart to space the nozzles?

Thanks for the help, folks!


Hello Martin .

Real good to hear from ya !!
Long time no see .

I have never run a charcoal unit so I will yield to others that have . :grinning:


Martin, there’s another way to make them easily removable. Steve Bowman told me about the Double Tapped Tank Bushings where you can thread in a pipe, but remove it when you unscrew the bushing.

You can combine this with a length of some schedule 80 1.5" pipe, buy one long length cut in half and cap off the other end with a welded plate.

For an easier weld I’d suggest something like a Merchant Coupling in the 2" size, they make Half Couplings for them because you’ll only need half anyways. Or you could just buy a regular 2" iron coupling and cut it in half.

For the nozzle holes, I’d give them plenty of space but with my 2 Liter engine in an updraft flute I did real well with 5 1/2" holes. Probably was overkill for my engine but she never ran too hot. I think I’d try for that, so 10 total 1/2" holes.


Many thanks, Mr. Wayne, good to hear your email voice!

I feel bad, guilty I drifted off to the black hands cult! But they assimilated me many years ago. It’s just so easy to run small engines that way, and Ray Menke now has hundreds (?) of bags of engine grade charcoal he’ll probably let me “borrow”…

Still plan to finish my other wood gasifiers though!



Many thanks, Cody! Why did you choose updraft, if I amy ask?

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I had an updraft at first just because of how simple it is.

But a downdraft charcoal will be much more useful in my opinion. As charcoal is stored it absorbs moisture and a downdraft can use that moisture to crack into hydrogen just like when we use a water drip.

Actually if you use a moistened enough fuel you don’t need a water drip, the reaction is kept just cool enough.

The only way charcoal doesn’t absorb water is if you’ve hermetically sealed it off. Bagged up it’ll absorb it. But that’s a good thing because then you won’t have to add water.


Even in this dry climate where I live the char coal is going to be at least 10% moisture stored in feed bags.


Amen to the charcoal water absorption! My Mulefier is an Simple Fire updraft. Has a tight fitting puff lid but the charcoal absorbs so much moisture here in South Central Texas that is hard to keep it out of the engine.


Do you run a gas cooler on the simple fire? Should help extract some of that moisture. I found my filter box was catching most of it since my flex exhaust ran downwards to the box. 6 feet of pipe seemed to get a good bit out.

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Ribbed flex tubing to a Southerland cyclone to a spa filter. Then Gilmore style RV sump hose to the intake. Still lots of moisture. Use magnets over a Great Stuff bifurcated roll bar intake for air mixture. Should be a pic here, but if not will post one.


Hey Folks, I’m trying to do some calcs on optimum nozzle diameter/area, presuming just one circular nozzle at this point, for calculation simplicity. I’m referencing an old Yahoo Group posting (2012) where Max and Gary Gilmore and I were discussing flowrates, and using Max’s calculations from same. Then I’m trying to make sense of them, using the Kaupp reference (in the Library and elsewhere), pages 73-75. And I’m coming out with some weird numbers, maybe a careless mistake on my part. So, I’d appreciate you guys taking a look. I will see if I can figure out how to get Max’s attention, as well:

So, for a 4.9L (approx. 300 In3) engine, at 2000 RPM:

First, Cody initially used Koen’s spreadsheet for a 4.3L, which arrived at about 1", or 25 mm. Ratio-ing the results up to a 4.9L (14 % larger), 1" nozzle is 0.785 IN2, so 14 percent larger is 0.895 IN2, or an increase in diameter of only a little bit, or a 1.07" diameter nozzle. Seems small. Of course, Cody later tried a 2" nozzle - a huge jump.

Back to Max’s volumetric calcs:

4.9L x 2 (RPM in thousands) x 3 (Max’s “combined stationary factors”) = 29.4 Liters/sec
In SAE, 300 In3 = 0.1736 Ft3

0.1736 x 2 x 3 = 1.042 Ft3/second = 62.5 Ft3/min (CFM) = 106 M3/Hr = 1.77 M3/min = 0.029 M3/sec
This 106 M3/Hr is sensible, given the numbers in Kaupp, page 74, which shows Useful Gas Range (M3/Hr) of up to 85 M3/Hr, for a 25.4 mm (1") nozzle.

Choose a 1.25" nozzle (guesstimate)
Nozzle Area:
1.25 In diameter nozzle = 1.23 In2 area = 0.0000202 M2

Velocity through this nozzle, based on above flowrate:
0.029 M3/sec divided by 0.0000202 M2 = 1437 M/sec ??? Wow, that’s the speed of a bullet! Something is wrong, likely a temperature correction due to gas temp, or a mistake on my part or ???

The highest air velocity shown in Kaupp is 218 M/sec - which generates great gas composition, if nozzle-melting temps.

Thanks in advance!

Bear in mind I have recently had issues with a single nozzle for charcoal.

I went a total of 4 miles before melting down my nozzle. I even had it oversized to reduce the intensity of the heat.

The nozzle was even pointed downwards to keep the nozzle away from the reaction.

I’ve had the same issue with a thought to be unmeltable silicon carbide nozzle with the same truck. It got so hot the silicon turned to glass just from idling.

I think a Mako design would be more suitable, the heat is more evenly distributed and you could line the hearth with ceramic wool blanket to keep the heat off.

In an updraft the nozzle won’t melt if it’s placed directly below from the very bottom or through the side with a 90 degree fitting to point it up. It’s away from the rising heat.

Bobmac, Kristijan, and Don have also had great success with a double flute downdraft.


Thanks, Cody. Did you add steam or EGR to those nozzles? No getting around the forge-like temps in a charcoal gasifier - except by doing one or both of those - and winding up with better gas as a result.

Double flute sounds intriguing, spreads the heat over an area, but I think I’m going to try a Pederick style, first. I have the heavy plate, an idea on how to construct it. And I don’t know of anyone else who has tried one, recently. They were said to be reliable.

I just would like to apply some math/physics and past lessons learned to try to figure out how big to make the nozzle hole - try to get it close the first time.

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A good downdraft gasifier doesn’t need water addition, and that was the intent of my build. It was in the Pegasus book from here in the library, a cross between a Downdraft and a Crossdraft. I just don’t know if a single nozzle is very beneficial. It’s hard to make sure you’re getting clean gas with only one nozzle. It’s never if but when you get some bad charcoal in the gasifier and I’d like the system to be able to handle a little dirty fuel.

EGR gives no benefit other than reducing temps, water drip works if you can atomize the water either by steaming it or making a sort of water carburetor. With downdraft charcoal you can use damp charcoal and the moisture will keep the reaction stable, but I think it works best when spread across multiple nozzles.

I would almost build a downdraft charcoal gasifier like a WW2 Imbert with a fully hot hopper surrounded by the gas exiting jacket, which it’s known with wet fuel the system would steam crash and cool the reaction too fast when on raw wood. I think on charcoal, you’ll get a similar event but charcoal gasifiers obviously run hotter, and the steam will cool down the reaction to better levels.
Think Imbert with a WK sized active burn tube but no restriction. Probably built up like a WK core entirely for best results.


Cody, my apologies, I should have pointed out my fuel spec for this project, early in this posting. You and I are building different gasifiers for different fuel specs. Mine is for engine grade charcoal ONLY (fully pyrolyzed, ground and sieved - by Ray Menke or myself), and you are seeking a gasifier more tolerant of a mix of partially pyrolyzed charcoal, and/or some wood chips, etc. Ray and I pull out any partially pyrolyzed “brands” (as Ray calls them) during grinding, or before. (during grinding they become obvious as … they are difficult to grind)

Yes, a lot of fuel prep work, and some wood BTU used in making the charcoal. I kindof look at it as, “you can pay now, or pay later”. Later being with a more complex gasifier and possible engine-damaging upsets that must be avoided. This does not mean I am anti-wood gasifiers, only that I prefer to simplify the process by doing the fuel work upfront for my vehicle gasifier, instead of using a wood gasifier. Having said that, I have LaRosafier, MPM Imbert and incrementally-fueled, stratified downdraft (sometimes called a drizzler) wood gasifiers about 50 percent completed. I may or may not ever put them in a vehicle, but will see. I do intend to complete them.

Engine exhaust (aka EGR) does contain water vapor and CO2 that are raw materials for making more fuel - in a charcoal gasifier. Neither water nor EGR is typically used in a wood gasfier because they are not needed - due to pyrolysis gases and water found chemically and as moisture content, in the wood.

I’m a Simple Fire user, for about 10 years now. I have one on a Honda XR-100R (you can find it by searching my name, here on DOW), and another powers a Kawasaki Mule. Both are updraft, of course, and moisture (likely from the charcoal bed) has caused problems, as I didn’t do a good job of dropping it out, and I didn’t run engine out on gasoline after a charcoal run, in one (expensive) case.

So, the updraft moisture content aspect tended to make me poo-poo a future updraft build. The ash cleaning with gravity and gas flow aspects of a downdraft seems better. However, upon a lot of study, I do like the cooling and partial filtering aspects of the updraft, charcoal gasifier. So, I am going that direction.

One or many “nozzles”, for an engine grade charcoal gasifier? The Whitlock forge and flute builders are onto something, no doubt, based on success. I haven’t gotten much in the way of design suggestions for flutes for my 4.9L, but I did not reach out to each of them, directly. One thing about having only one nozzle in a charcoal gasifier is that you can pretty much control the reaction in that one location, whereas if multiple nozzles/holes had partial flow, you might wind up with something funky. Anyway, the single nozzle Simple Fire has worked pretty well.

So, back to the Pederick. I have been fascinated by its simplicity, novelty and supposed reliability. Not much different than a Simple Fire, except it has a great way of vaporizing added water - which I prefer to “moist charcoal” in a downdraft, because it is more controllable. And it has no “nozzle protrusion”, which as Max points out, is “what gets you”. Why Gary G. went to the “forge tuyere” design. Your idea of adding a couple more nozzle holes to a Pederick plate is probably a good one, but I think I’m going to start off with just one, and go from there, keep it simple. Now if I can just find a way to figure out what nozzle diameter might be appropriate for the 4.9 L …


Someone correct me if I’m wrong, but I think this only happens when running on gasoline. You don’t get it when running on wood or charcoal. The only benefit is it cooling the hearth to help keep metal parts like the nozzles from melting.

Garry C


Garry, I was waiting for a third party to answer you, but absent that, the two primary woodgas (or charcoal gas) fuel gases are hydrogen (H2) and carbon monoxide (CO). When you burn them (or, oxidize them/add an “oxygen”), you wind up with H2O and CO2. Good that that asked the question, for clarification.


Garry, you beat me to it.

Martin, gasifying dry charcoal, specialy in a updraft gasigier will produce litle to no hydrogen. So no water produced in the exhaust and no hydrogen again using EGR. Wich is a real bummer as its a great way to controll heat and improve fuel efficiancy. It just sucks at giving power…

You can test this your self. While runing the engine on chargas, squirt a few drops of water in the air intake of the gasifier. Imediatly the engine revs up significantly and also it wants a leaner mix due to extra hydrogen


So, around here it is so humid you can almost cut the air with a knife! You are burning ambient air in the charcoal gasifier. That is going to yield some water vapor, and hopefully a little hydrogen. Admittedly, not much hydrogen. But that water vapor in the gasifier product passes on through to the next stage, the engine. Meanwhile, the engine is mixing humid air with this charcoal gas (with some amount of water vapor in it, from the humidity, as mentioned above). I wish it weren’t so, as not running my Motofier on gasoline after the long Mother Earth News run, ten years ago, or so, left me with rusted rings and a stuck piston, necessitating a major overhaul. (It ran so well that day that I decided I never would run it on gasoline, again. Big mistake, not flushing it.)

So, water vapor is in exhaust, here at least - no way around it. Certainly you would agree there is CO2 in the exhaust, as that is what happens when the CO is burned. CO2 is a gasifier fuel raw material, provided you have sufficient excess heat. Bottom line, exhaust contains some H2O and CO2, in this location.Processing: 20131103_143307.jpg…


Kristijan, if you would, help me with a dual flute design for the 4.9 L. How many holes, of what diameter? How far apart/over what total width (of the flutes)? Holes no closer than 5in from sides of gasifier? Thanks!