Nope. If you’re making weak gas, this won’t account for it. Nor will it compensate for air leaks in your plumbing.
It counts on the fact that, once the gasifier is up to temperature, the gas quality is relatively constant.
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Hi, Brian!
Yes, this question has been debated over 100 years!
in every woodgas book!
No one is comming downhill from the Himalayas, anyway… so if the motor goes well with its gasifier system on idle for 15 minutes and more, there is just a little “noch” moment in the retaking of driving power, when the land is flattening out, or a new uphill is about to be “taken”.
With a manual gearbox you can use the motor for pumping more gas than the idle gas need, by swiching off the ignition and giving a little foot (pedal) gas. That is called motorbraking…
Perhaps too modern vehicles also will make a mess with all kinds of shutdown-functions when they are deprived of current?!
Hope you can circumvent that!
If you reed the books, you will learn, that a hearth after heavy drafting can produce an excellent gas, because the steam boiling in the silo pushes out through the hearth, and no air is comming in with nitrogen, which normally will dilute the burnable parts of the gas by ~1:2!
If this goes too far, the motor can be suffocated by the lack of secondary oxygen (air).
This is typical with T-mixing, where the mixing ratio (air/gas) happens above the common throttle.
In this case, the high succing-vacuum is under the common (for both gases) throttle.
Above the common throttle and the succing vacuum you have the two (freely compeating) entrance routes of free flowing gas and air.
This “competition” is under normal power conditions a place with a swift flow-through, and in consequens of that, you have flow resistances in both entrance-routes.
With this flow-through, you can balance the flowresistance between the routes with the traditional hand-regulated air-flap.
That is the traditional way to set the mixing-ratio.
But, when the gasgenerator is pushing out more gas than needed, the mixing ratio is upset, as the t-mixer is dependent on setting the flow resistance equal in both arriving routes (legs).
When the gas is flowing into the T-mixer without succing, it is impossible to balance the “flowresistances” and the air/gas ratio!
…
This will not happen with the twin-flap dispenser, because it is setting and controlling both arriving air and gas routes’ flow resistances independent of which “mood” the gasifier happens to be in!
Pushing or resisting…
The twinflap dispensing is dependent on the always
equal flow areas and equal pressure drops
over both flaps — from cranking to modest high power levels.
At WAT level the twin flaps are no longer the dominant resistant for flow control, so the flow routes for air and gas have to be made absoutely identilcal from the sampling points for the flow routes to the dispensing flaps, and to the swirl mixer.
Sampling points for the membrane, which regulates the arriving air pressure according to the arriving gasflow pressure, when there is a definite pressure drop in the gas line.
Max
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Hi! Pete, Sean, Matt and Marvin
Yes, if sensitivity gets you sole! Now a full regulation range within 0.5" WC is good enough for proper and smooth operation. Why then expand the range of service needs with electronic gadgets?
If you start without any electricity available where is the advancement?
By the way, start up does not need any prebalancing for minute intake flows; the twin-flap dispensing makes that with help of the sucking vacuum… INSTANTLY!
Max
Just as an update I got the bearing and shaft in and it will not be good for this. Very rough movement and it would hang up in places. Pretty low quality. Back to looking for something else.
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Bummer plus 20 characters
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Max, I’m afraid I don’t understand the cranking gas part. I see the stop screw limits the stroke, but what is the chamber and how does it work?
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That’s a vacuum bellows which governs the vacuum at cranking. Works like this:
Engine off, bellows relaxed, spring pulls bellows open. No pressure on gas pedal, throttle is open 0%.
Engine cranking begins, low vacuum pulls on bellows. Begins to open throttle when sufficient vacuum exists.
Because of the built up vacuum, equal quantities of gas and air are metered in past the twin flaps. Engine starts instantly on correct mixture.
Engine running produces lots of vacuum, draws hard on bellows, overcoming spring. Pushes on throttle more, raising idle. Continues to raise idle until the stop screw is met. This determines your “low idle”
The hand idle is completely independent and works like Wayne’s string idle control. It must be completely relaxed for the vacuum bellows to work at cranking. When the engine is running and needs to idle higher, this is adjusted to produce a higher speed. Can be a crude cruise control as well.
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03.08.15
Hi, Andy!
There is plenty of time to evaporate gasoline-gas squirted from a carburettor, before attempting to crank it going. Especially as cold.
The throttle can — and is set for the air needed for a comfortable idle.
With woodgas there is no evaporation; gas and air have to FLOW together in correct proportions FROM the FIRST crank sucking!
The only way to avoid random, disproportioned mixes to emerge is to start from no-flow vacuum.
With a vacuum of 1 to 3’ (feet) of water, the identically opening flap-gaps are
dispensing equal flows of gas and air!
The ”bellow” is overcomming the set spring tension when the cranking acheives the desired vacuum. Then first, the flap-gaps start opening and a balance between pumping and flow is established.
The stop screw is there to avoid fatal rushing, as the vacuum jumps about 5 times higher when the motor fires!
Do not use handgas/idle during cranking, or you ruin the needed vacuum!
Ask more if this does not cover what is important or has been overlooked!
Max
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Good stuff Max!!!
I like pictures 
HI MAX,has this unit been been tested,or set up being used on truck size motor.and if you could name the componets,i could understand it better,I dont know the simbols, the auto adjust mixer would be nice too acomplish at some point.THANKS
Yes, this setup has been used on Dutch John’s Volvo and truck. I don’t believe he had the startup bellows however.
05.08.15
Hi, Kevin!
”EARTH” is used in electrical schemes, but also in old mechanical sketches.
The meaning is probably selfexplanatory… riggid, uncompromising, permanent ground for attatchment.
This dispensing technique with balanced flows, first developed in Sweden around 1920+ came to my awareness about 1984, when lending the book GENGAS.
Still, inspired by respiratory technics I had my own version tested 2 years earlier…
In Germany 2004, I had an opportunity to apply this system on a big former Diesel motor 6 cylinder Valmet, rebuilt in Holland for natural gas.
Driving a 85kW 3phase generator.
It was a glorious day as a 15 person international crowd looked on the very first start on woodgas.
Instant start on woodgas, and the landlady served the whole gang with
Champagne!
That was a bit before DJ started to apply this system…
Here follows a new copy of the scheme with filled-in designations…
Max
Thanks max ,You have an interesting history with wood gas,i copyed both pics too my computor for lator when i get time too spend on automatings the mix , Thanks for shareing your ideas,When Chris Saenz gets it working and simple fied on parts too use, maybe YOU guys can post an easy for dummys too build plans cheap, THANKS
Little update on this. I’ve redone the diapraghm material a couple times. Currently I’m using heavy-duty lawn trash bag material. I think it’s 2 mil.
I set up a jig to hold the diapragm upright, for bench testing. The loop is a water manometer, which will tell me how much suction I’m using to drive the valve.
The less suction it needs, the better. The target has been 1/2" of water column.
I tested the movement using a cheap fan, which only puts out volume and not pressure. Still, it was able to “blow” the valve open and closed - I measured this at only 3/16" WC.
Video:
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Good evening Chris saenz, nice project,interesting. hope it works good when done, I gess it will help a lot.Thanks for tackeling the add on project.
Would it be possible to repurpose the old cruise control vacuum modules for this?
Hi, Matt!
Basically a diaphragm with one side open to the air and the other one closed and connected to some other ”vessel” will do some job based on a pressure difference to the atmosphere…
Active diaphragm area times the pressure difference gives the power…
If jou are going to ”destroy” the speed controller you have a good ”bellow” to set the cranking vacuum against a suitably strong spiral.
Max
Yeah that is what I was thinking they are already made and probably could be found in the junk yards. If these older ones all gone then maybe a brake booster could be modified. Might save some time and effort 
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