Uff, the debate has gotten really lively …
Me and Kristjan and I spent some afternoon chatting about the mixers, but I am attaching a sketch, this is supposed to be with an adjustable gas / air ratio and less downtime due to dirt
5 Likes
Tone got this idea from the Bosch K jetronic injection system, the kind JO had on his Rabbit and l had on my Mercedes. It does make sence, since it already does the job. Just instead of mixing the petrol in relation to air it wuld mixwoodgas in relation to air.
I think this wuld work great but wuld require some math, carefull analisys of the originanal flow meter etc… but once we get things done we shuld be able to maks a 100% foulproof automixer.
Tone, now thinking about it, you were right on the begining! The gas shuld pass the metering float. The gas is the variable (different drag on the gasifier) and IT must dictate the amount of air (constant pressure) to be metered in.
7 Likes
Max, see for yourself … or could I install more things? 
automixing seems to work well. on one side it is connected to gas pressure and on the other to that of air. As I said before, the space is very limited and I try to build without equal-geometry flaps
8 Likes
Wow, Thierry! You really put down some effort under the hood. I like the little piece of bicycle-chain on the valve axle 
6 Likes
Hi Thierry,
A make-more-space solution would be to move the battery out from under the hood area.
Older US cars and trucks would put the battery under the passenger side floor boards.
If you do this build with good stout wood soaked in preservative to endure the slow battery acid fumes deterioration.
Other late model FWD chassis’ underhood space can be made removing some of the elaborate air-in hush boxes. Live with the air intake hissing tones then.
Regards Steve Unruh
3 Likes
That wuld be extremely ilegal here. In a case of a car accident, first thing that gets done is to disconnect the battery. Hard to do that if you dont know where it is…
5 Likes
I did not know this equipment (Idle Air Control Valve (IAC),) Rindert, thank you for the very interesting information .you seem to say that a simple PWM could control the opening or the gradual closing of this “mini valve”?
I would like to be at this stage in my project but I think that before I worry about such fine regulation of the air / gas mixture, I still have a lot of work to do, but at some point I hope to achieve it 
2 Likes
Be carefull with those idle valves, problem is they seize up with woodgas and burn out. They have tight tolerances.
Just a warning that you dont throw to much work to something that will only work for a week.
6 Likes
Hi Thierry and Kristijan,
well with the idel valve, if you tune your woodgas air mixture to the rich side, you could use the idle valve for the air only. That way it should last longer.
But anyway, I would go for a small manual valve. You could mount it in the cabin and connect it with hoses (careful that everything is tight!) or make a longer handle for “remote control” from the cabin.
5 Likes
Thats my idea too.
The IAC on my Ranger got clogged and was sticking sometimes open and sometimes closed. So I had to take it off and clean it with carb cleaner and a cotton swab. But this was after 28 years.
I am still waiting for my pwm to come from ebay, so this idea has not been tested yet.
Rindert
3 Likes
Til, please clarify . . .
are you suggesting routing woodas in any way up into the passenger occupied space!!??
A NO-NO, never do.
Remote control a manual under the hood valve with cables instead.
Think light aircraft controls. Cables, rods and chains.
S.U.
7 Likes
Dear Steve,
sorry for letting you wait so long for my reply, had some busy days…
Of course no woodgas-pipes in a passenger space.
I had in mind mounting the valve in a way that only the lever would be in the driver’s (somehow in the dashboard). Or under the hood and remote controlled with cables or rods as you wrote.
Sorry again for being unclear.
Anyway, if its just for tweaking the automixer it doesn’t need much attention anyway.
Regards, Til
6 Likes
how is your gas mixture carb doing have you got any further in the design. i have been watching ad havent heard anything for a few days just wondering . what we need is a simple self regulating mixer keep up the good work.
2 Likes
Hi Til
what type of valve do you think you are using?
in principle only air will circulate in this valve (the air chamber being always (or almost always) at a higher pressure than the gas chamber)
should an IAC valve stay there clean? 
1 Like
Hi Thierry,
I thought about a small ball-valve, something like this:
https://www.buerkle.de/en/three-way-valves#similar
Just an example. I don’t actually use one of these.
An IAC valve should be ok, if only air is going through.
3 Likes
It looks perfect. I assume that it is working good?
Do you use it every day? has this done a lot of work for you?
Rindert
3 Likes
Hello Rindert, the car is in use every day, I drive from 50 to 100 km, the previous mixer did about 40,000 km, but it bothered me a bit, because at high revs it did not give full power due to the smaller cross section, but I made a bigger one. 5000 km, works well, gas consumption somewhere 9 liters per 100 km.
As you can see, the housing is made of a transition piece for pipes.
7 Likes
hello rindert, what comes out with your small diameter gasifier on the foto…?
ciao giorgio
2 Likes