86 Ford F-250 351 v-8 4bbl

Hello all my name is John wells, and I’m out in massachusetts pretty close to boston, anyway I’m working on my first build of an old pickup that we have retired, when I read about wood gas I was so exited I just had to try it! my project is in its finishing stages and I have been working on it pretty constant for a couple months … Ive been chatting with Mike LaRosa and a lot of other folks on the wood gas site on yahoo… every one has been very helpful with my build… so i decided to start a discussion hear about it… I’m ready for another test run tomorrow so ill post how it goes … so far so good ! but my restriction zone is a kitchen stainless steel pot… so I’m not sure how long it will hold up … but so far so good! a little about my system I’m using a 2" supply line of black iron pipe and i have 3 stages of cooling … 1 stage is a barrel in a barrel (oven) for drying the next batch of wood i run… after the drying oven… i go to a radiator that is simply 20… pieces of 3/4 iron pipe welded to 2 " tubeing top and bottom … the 2" pipe is baffled on the top to force flow dow and up … after this first radiator i go to a second that is 4 lengths of 1.25 id steel fin tubeing 7’ long this is arranged in the bed of the truck… last is yet another 55 gal drum filled with hay … on the bottom of my oven , first radiator second radiator and filter barrel i have drains with all collect to one condesate tank located under the truck mostly tar comes out of my first radiator and water from the second and filter … i may separate the water from tar with a separate tank but for now i see no need to… I’m using the original carb with a propane tank i have modified similar to a cyclonic filter for mixing the gas in place of the air filter. the air mix valve is located in the cab … (yes i know this is dangerous but I’m still testing and will relocate it under the hood with a cable later…) for now i can control the mix while I’m driving this way. the air inlet is 1" and seems to be letting enough air in. i have installed an electric fuel pump and a solenoid valve to shut off the gasoline (since the engine likes to suck the gas out of the tank with out it.) for now I’m switching the timing and opening a 2"plug to run gasoline i can’t change on the fly. … yet. i have pyrometers on the grate and the gas outlet of the gasifier, i have installed a wide band O2 gauge , and i am waiting on 3 vacuum gauges… from global … they are taking forever to arrive! been ordered for a month now!..anyway i plan on having them at the engine and at the gas outlet of the gasifier … and the hopper…

so far i have clocked 50 miles on my set up and have maintained speeds of 50 miles per hour… not bad for a first run! pick up is sluggish and i notice sometimes i have more power than others… but I’m a newbie… I’m very happy with my first build so far and i have learned a lot! things that worrie me are my restriction zone melting/ and if i have enough of a supply line to the engine … so far 2" seems ok but could i run the gassier with less vacuum with a larger supply line? i.e. less intense heat in the reactor? … i get nervous when i see it at 1700 f i like to keep it 1300 to 1500. f

in my gasifier i have a 3.2 inch restriction hole in a 7" deep stainless steel kitchen pot… just above the pot is a ring of nozzles about 18 .2 in diameter around. 3" above that i have 5 nozzles .5 inches and all nozzles are pre heated . I’m still tuning the two sets but i think its making good gas!..so thats my build so far ill put up some pics later cheers all and thanks for this great web site and forum for discussion! john.

Hi John, welcome to the site!

I have to say I’m surprised to hear you’re getting to 50mph on that setup, but if it works - great! Looks like you have clean gas coming out.

Definitely think about a second 2" gas line. It will allow you to pull the gasifier harder. Also the higher temps are good - like Jim Mason says, stay above 1500 or you will have tar in the gas. 1700 is better, but you will probably need to use heavier materials for the restriction zone.

The restriction sounds too small for that truck. I’d want at least a 5" opening in for a 350 motor, much less and you will be overpulling the gasifier. I know Mike gets away with some smallish rotors though. Good to err on the side of hotter and less tar, even with less gas output.

Post a video of you driving it around!

Good morning John,

I thought I would add my two cents worth. Make sure you have your cooling tubes so they can be flushed with water. In less than a thousand miles your tubes will begin to plug but they can easily be washed out with a garden hose. All the tubes will not clog and there will always be enough air going through to run your motor but the cooling capacity we be reduced.
You didn’t say if you are running a standard air filter at the carb. If you are it will also plug after a few hundred miles.
I don’t use an air filter going to the motor but I make sure I use no more metal pipe after the hay filter. (It will scale off and end up in the motor.)
On the subject of the single two inch line going to your motor.
I have always used a pair of two inch PVC pipes going to the motor compartment. I have shut of valves that are controlled from the cab so if I want to switch to gasoline I can kill all the wood gas going to the motor so as not to run the truck too rich when switching over.

After reading you post this morning I put about twenty five miles down to test the difference of one pipe vs. two.
With the v-10 8L motor cruising at about sixty mph and about 3/8 throttle I would kill one of the two lines and could tell no difference in motor power or sound. I also could see no difference in the vacuum reading on the gasifer. I tested again at almost full throttle (I avoided the truck going to a lower gear) and could tell no difference in the vacuum readings or motor sound. The third test was WOT allowing shifting to lower gears with the rpm going up. I noticed about a 10% reduction in the gasifer vacuum readings comparing one line to two.
Please remember PVC pipe is cheap.


Hello John,

I forgot to mention one thing about what you said about the truck running sluggish.

With a gasifer system the truck will never run the same two days in a row. When we are running on gasoline each gallon contains the same btu and the computers know just the amount to inject, the sensors adjust for ambient temperatures ect. With wood gas there are just too many variables. Size of fuel, moisture content , ambient air temp, how well fuel is falling to the reaction zone , how long the gasifer has had to warm , whether you are in the beginning of a load of wood or whether finishing it.
There will be some days when you think your truck is running it’s very best and tomorrow it does even better, then when you are ask to demo it , the truck may run crappie.

Try to store as little hot gas as possible (all it needs to pop is air)

The first sign of bad gas will be a sticky throttle after the truck has set over night.


Hi bruce a gate valve. no i use ball valves… but which valve are you referring to?


I was referring to the air mixer valve with the 1 inch line to let secondary air into the woodgas as it goes into the engine. A gate valve allows for finer adjustment and that can make a huge difference in performance. Thanks.

oh ok thats a great idea actually! i can run a rod to the valve and just extend the handle into the cab with a gate valve this is easier! also the fine tuning is something i hadn’t considered… do you feel 1" is big enough? i can go bigger…


If you add another gas pipe to the engine you may need more air. I use a 2 inch butterfly valve now and I am adding a gate valve for fine tuning on my Ranger. I do a lot of trial and error stuff.

Well i like being able to adjust the air fuel mix on the run!! what a difference! i actually passed someone i thought was too slow… 65 mph with little effort… although i haven’t hit the 4 lane yet so i don’t know a top speed … still waiting on vacuum gauges … the truck runs great and I’m experimenting with wood chips for fuel … as this is a new concept for me dry wood chips are not easy for me to come by but what i can find seems to work well … i clocked another 20 miles with just wood chips this time … the chips burn faster but they are free and require no cutting or splitting and i have a mountain of them from the tree guys… I’m very exited about the way the truck is performing. … today i had the motor running in under 10 minutes on wood chips and went for a little drive things went well … still fine tuning it but the more i timer with it the better it gets… wood chips seem to bridge much easier and i may re figure my nozzle design to help them flow better …but i hit 65 mph and with the mixing valve and o2 sensor i can get much better power and drivability … thats it for now…

pic is a flare off wood chips


Hello John,
Hey, that is great news. Always a good filling to go around the petro cars.

Keep in mind the smaller fuel you use the more likely you might make tare. If so the first sign will be a throttle that fills stuck or sticky. If your throttle is stuck when left overnight , make sure you turn the engine over by hand before you start it up.

John, your project just got featured on the front page. We’re going to feature different projects from members every month. You get March!

John, Now that you are the featured vehicle, you might want to wax that baby up! LOL Nice job.

nice ! :smiley: i took a couple more pics today ill try to attach… thanks !

in my truck i have 3 barrels one is a filter one the gasifier and the last is an oven using the 700 degree gas to dry wood chunks…the radiators are in the bed …since this is my first build i went for simple next time ill put the cooling tubes on the sides like sideboards…that will make the truck more useful !


Hello John, I was wondering if you could show me your carb intake setup? I am building a carbed 460 f250. Thanks, MikeyB

sure thing … ill briefly describe what i did… i left the original carburetor and installed an electric fuel pump (to replace the mechanical one … i have since learned that i have to install a solenoid shut off valve in line with the fuel pump… because the engines vacuum will pull gasoline out of the tank even with the electric pump shut off… so with the gasoline positively shut off … on top of the carb i took a 20 lb propane tank (barbrque grill size) cut a hole in one side the same size as the carburetor … and then cut the middle out of the propane tank … then welded it back together … it now looks like a flying saucer… then i welded a 2" inlet pipe so the gas would cyclone around the saucer thus mixing the air well before entering the carb… then i welded another 2" pipe in the center letting fresh air directly over the center of the carb… make sure its all air tight … i then put a ball valve on the second pipe and located it in the cab so i can adjust it… in the future ill put the valve in the engine compartment for now its working fine… basically its an air filter with the inlet coming in on the edge so the gas wil swirl or cyclone before entering the carb… then another inlet with the pipe extending into the unit just over the center of the carb for the fresh air… hope my description is good … ill take some pics and post them in the daylight…



You wax eloquent with your descriptive words but I’m a visual guy :slight_smile: For me a picture is worth…well you know what they say. Look forward to seeing the photos.

Have fun in all that snow.


Here you go… its a glorified pot with a couple holes it it :wink: you will see a 1" elbow with a 1" pipe on it … that extends into the cab with a 1" ball valve on it… the other 2" line goes to the gasifier … you will notice a “T” missing the plug thats because i ran it on gasoline last… to run on wood gas i put a plug in the hole and adjust the ball valve according to my O2 sensor reading… hope the pics help…


Hey John, could you fill us in a little more on your nozzle set up? The way I understand it you have 2 rows of nozzles, one row with a lot of small holes and another row with 5-1/2" holes. Do you have a drawing or picture of that? What was your reasoning behind that configuration? Thanks. Don Mannes

well the first set of nozzles i burned into the bottom of an old 100 lb propane tank with a torch the bottom of the tank had a “foot” which was a hollow cavity made by welding the foot to the bottom of the tank… i figured it would be a great manifold… so i burned about 18 holes around the bottom of the tank about .2 in diameter and welded pipes to the outside of the tank to supply air… the set up failed… i then moved up about 4-5 inches and put 5 nozzles .5 in diameter and extended them into tank… thus giving me another set.then i added a stainless steel kitchen pot to the bottom for a restriction zone… its about 7" deep… i just left the first set and blocked them off … then i got the idea that maybe letting air in at two spots might be a good idea so i just opened the first set. letting a little air in … it seems to work well and i have good gas … wether it really matters i don’t know … but when I’m flaring the gas i can see a difference from just one set to the two… and i think its a better gas… but i have not fine tuned them yet… basically i have two sets because of an accident in my first build… i actually don’t have a pic of the two sets but i have some from the initial set up … ill see if i can post them .ok the last two pics are with both sets … you can see the pipes entering the tank at two levels… hope it helps … sorry i have no real dementions ill take some accurate measurements next time i pull it apart…