Gasification

1996 was the change to OBDII, where the computers are standardized and reliable enough that dyno testing is not usually done for emissions tests. Prior to that, it depends upon the truck brand and model, but 1980 is a reasonable guesstimate. Basically you want to find a truck that is carbureted rather than injected. Things will be simpler if you use manual transmission too.

The Wikipedia article provides links where you can to learn more.

Thanks K fry

You can put a carburetor on a fuel injected engine just by making an adapter on the intake manifold and simply disconnecting the fuel injectors. The computer may not like it but that does not mean the engine itself will have any problems with it.

I run a propane system on my 99 Ford F250 and all I did for the propane operation was to add a vapor mixer ahead of the throttle body and have a switch that turns off the power to the fuel injectors.

Most fuel injected fuel systems are high pressure, much higher than carbureted systems. You would most likely have to disable the tank mounted fuel pump and or change the sending unit/pick-up on the gas tank to an older style. You could still use a electric pump, but one with a much lower pressure and or an adjustable regulator. Anything over 15psi going to a carb is going to give you real problems.

I dont think he is planning on using the carburetor itself to run gasoline through it.

Wood gas fueling is a vapor fuel based system.

We're gibbering about a suitable donor powerplant for a gasifier retrofit here not retrofitting a carb to a native EFI engine.

Wood smoke and creosote vapour powered......

Where's woodpower when you need him?

i think you've been misled on the prospects of even getting it up and running.

no internal combustion engine would be suitable. a steam powered engine would be more practical if you're dead set on using wood.

call jay leno

Don't know where you get your info, but wood gas was used extensively during WW II practically worldwide except for the USA. It was used on tractors, taxicabs and trucks, and no doubt stationary applications. Mother Earth News had an article on this topic back in the 70s, and the web has numerous how-to articles. Some are more complicated than others. Donor vehicles can include vehicles at least up into the 80s if you want one that came carbureted. I'm not a mopar expert, but Fords early electronic ignition (used with carbureted engines) was very durable and simple to implement and GM's was even easier. I seem to recall the MEN article stating that a long-stroke straight 6 worked well for this application, but I can't be positive as it was a long time ago that I read the article.

If your looking at GM full-size pickups, 1990 would be the last model year which used a carburetor, there are some exceptions being which body style you choose. The '88-on newer "Silverado" body models are TBI and are computer dependant. 1990 For Ford full sized pick-ups is also their last year for carbs, '91 and on are computer dependant. 1990 for Dodge also is the last year for carbs. Of course there are some exceptions. Although some of these models may have some sort of computerized ignition management, that can be disconnected/by-passed or removed easily by installing an older distributer.

Really the more I thought about it there should not be any reason that a wood gas system could not be put on a EFI engine.

All of the vapor mixing components would go in the intake system ahead of the throttle body just the same as they would go in ahead of a carburetor.

I would think that setting up a newer vehicle with a wood gasifier would not be any different. In some ways it would be like my propane system and be easier being the fuel system can be shut down just by turning off one power supply wire that feed the 12 volts to the fuel injectors and/or the fuel pump and leaving the rest of the system to continue on doing its own thing.

The check engine light will probably come on but thats not the end of the world!

My suggestion is to stay away from any vehicle with an O2 sensor, rather than worrying so much about the computer itself. I believe the earlier ones were much more succeptible to fouling & this can cause driveability concerns if the computer is trying to correct spark timing etc.

If I were doing this, I'd try a Ford with a 300 ci straight 6. Simple, durable (in my experience!) & lots of room under the hood!

I thought the O2 sensors just controlled air mixture...

In any event a resistor of an appropriate value could solve that.

Thinking about it now, there's no reason you wouldn't want to have stoichiometric combustion happening regardless of the fuel.

The woodpower arrangement could be made a little less Heath Robinson in its setup and operation if the O2 data could actually be put to use.

The O2 level in the exhaust is one of the main variables of the fuel injector control algorithm ratchetting away inside the ECU.

The PWM signal to the injector (just need one) could probably drive an actuator for a throttle on the wood vapour line (2" pipe?).

The engine would then again be working in closed loop with all its feedback mechanisms intact. Dual fueling becomes relatively easy this way too.

The knock detectors would get the timing right or at least retard it if your best-guess fixed-timing distributor twist was too advanced. Not sure whether wood gas has a citable octane or equivalent or if the standard timing would work just fine.....need to faff with that either way you go.

If a stoichiometric burn could be achieved then the catalytic convertor might even survive. Pass emissions testing maybe?

Another thought here. With another one of the 7 remaining injector control signals you could control the gassifier output based on demand in addition to how much is metered into the engines air intake airflow.

By embracing the tech instead of avoiding it your choice of suitable donor vehicles gets a lot more interesting, as does the end result.

Interesting point. O2 sensors just output a signal, and as I understand it OBD II computers can respond with ignition mapping changes as well as injector control- I could be wrong & please feel free to correct me if you know better.

I was thinking of problems from unburned creosote etc, but if you can actually utilize the O2 sensor signal to adjust the gasifier- it really does open up options. This project is starting to sound quite interesting.

Unfortunately O2 sensors have a rather narrow working range plus need a fair amount of exhaust heat to work.

Also they are a voltage output device that cant be replaced by a a simple resistor. The computer needs to see a constantly fluctuating signal from them to see them as functioning. Without that correct voltage level and fluctuation the computer will just resort to using a predetermined fuel map to fire the injectors.

As far as ignition timing goes that usually gets adjusted for by the knock sensors and RPM.

On my 99 F250 the O2 sensors always log in two error coded when I am running on propane. One is lean A/F ratio being propane runs much leaner than gasoline and the second code is always for them running too cool since propane burns much faster and more efficiently resulting in far lower exhaust temps.

The odds are with a wood gasifier the O2 sensors would never register anything useful that would work in a closed loop control system.

More over I would be curious to know why this guy want to try this? Is he to poor/cheap to buy fuel or is it a just to see if it works experiment?

So you reckon the exhaust would be too cool?

Wood gas burns hot enough in the combustion chamber to provide enough power to propel a car at speeds and loads similar to closed loop conditions when burning gasoline. Figuring that the thermal-mechanical energy transfer mechanism doesn't change its efficiency with different fuels then the waste heat coming out the exhaust ports would be the same and promote similar temperatures at the O2 sensors.

If the exhaust was cooler then that would mean that engine is more efficient and I don't see how that can happen. You need the same heat in the engine to get the same power out the crank and the waste is the same....

Happy to learn mate.

Actually the conversion of fuel energy into mechanical energy in an internal combustion engine is not any where close to the being the same for all fuels.

I have been working with propane fuel for many years now and have running on an number of vehicles and engines and I can assure you that you that not all fuels burn the same or convert their chemical energy into mechanical energy equally given identical combustion conditions.

On my 99 F250 when I am running propane the O2 sensors always read than the A/F ratio is too lean and that they are not reaching operating temp yet the engine itself does not have any noticeable change in its power or fuel economy despite propane being considerably less potent than gasoline on a per volume comparison.

Every fuel has its own ideal burn rates and conditions relating to its thermal properties which are what dictate how effectively and efficiently it will convert its chemical energy into mechanical energy.

From what I understand wood gas tends to like a lower compression ratio and lower RPM to be most efficient when compared to gasoline due to its slow and relatively mild combustion properties.

Roger that. Sort of. More reading and experimentation may be in order.

Thanks everyone for your constructive comments.

tcmtech: I am a little disappointed that you felt a need to throw in insults (cheap or poor) with your answer. Sorry if I misinterpreted your comment.

Anyway, I'm neither cheap nor poor. Thrifty and self-sufficient, maybe. Several times in recent years I have been faced with no electrical power and little or no fuel availability for up to 10 days due to hurricanes and floods. During those times I have used up to 100 gallons of gasoline for my generator, when it was available, and when I could get through flooded roads to the gas stations. I can, and do, stockpile some gasoline for my generator , truck and boat (sometimes that's the only way to get to work, school, etc.), but I don't like keeping too much of it around for safety concerns and other reasons. However, I do have over an acre of trees that I can use to fuel a gasifier. I'm not totally sure if that is what I will do but I am trying to gather all the info I can before I make a decision. I would also consider running my generator on a gasifier system. I believe the smaller (13 HP) engines are a little easier to adapt for gasification.

A neighbor has a propane powered 17 kw whole-house generator with a pretty large tank but he runs short if he has to run it any more than about 5 days. And, the propane is expensive.

I wasn't saying you were cheap or poor and I did ask if this was for a just for the fun of it experiment but to be honest as someone who has gained a minor local reputation for doing AE stuff I do get approached by far more cheap and lazy ass's who are poor (mostly due to being lazy) wanting me to help them set up things like what you are suggesting just to save money or avoid having to actually work themselves.

We as a collective forum group here tend to get a good deal of similar requests as well that's all.

That said I am happy to give out any advise or knowledge I can if it is going to do some good.

In this situation diesel would be your friend.

Safe to store, economical to burn, doesn't go stale. Wet diesel engines start and keep running....

Diesel for your car(s) and generator. Get some oars for your boat.

hello all,

pre computer is best. electronic ignition module is ok. 6 cyl, long stroke is best.

the reason why best is that wood gas can only spin an internal combustion engine 2500 rpm max. so, a high reving low torq engine will barely get out of its own way. too low in the power band. you need a low reving high torque engine. something with a chevy 292 is ideal. (newer engine style, ease of getting parts). i would stick to 60's and earlier. do not expect a wood burner to ever equal a gasoline or diesel engine. won't happen. at this time the world land speed record for a wood burning vehicle is , i believe, in the low 70's. lots of info online.