After watching your video Kristijan, over and over again. I can see why you want the auto air/fuel mixer now. You definitely have a small compact design, Down Draft charcoal/brands/wood Gasifier working good and the Air/Gas Mixer will make it run even better.
I hope you don’t mind if I copy your design a little for my next charcoal/brands/wood build.
Bob
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If l wuld have anything aginst l wuldnt share it 
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I doubt it. If the AFM float arm is slow you should still get a proper a/f ratio, since its position dictates the fuel supply. The only reason I can come up with is the system pressure getting offset. The lambda voltage handels it, but since the sensor is not connected the system pressure should stay the same ???
Could it be your chargas a/f ratio is somehow getting offset (tight filter or charbed) when your dino tb suddenly opens?
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Well, I have no experience with this system of fuel injection, so I’m not sure if I should answer at all.
I thought similar as Jan-Ola. You use the system in a way that is not typical if you feed chargas below it an then just open it for more power wile the engine is already running with some power output.
Then again, if you drive down a hill and press the accelerator, it is a bit similar and should also work.
But as I understand, it is getting worse? The lack in response was not before?
Then maybe you get still some little bit of residues on it since the chargas inlet is directly below in the manifold? And with the towel filter, it might be possible that more particles are coming through?
Maybe just have a look on it if its still clean or a bit dirty.
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Koen posted some graphs a while ago that I think will help you. Reasons for Power Reduction on Wood/Chargas? - #53 by k_vanlooken
on page 26 of the same document. they say "for a good mixed gas (5700kj / m3, H2> 12%) the critical compression ratio is 11. a higher compression there is risk of engine clatter
I do not know how to convert a body of water per m3 air sucked by the engine, in mass water per mass of charcoal
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Hi Thierry, I would just do it this way, no math needed. If your engine starts to clatter or what I call engine knock, a pinging sound. Change the Air to Fuel Mix first. If there is no change the H2 is to high, or the advancement is to far ahead of top dead center or your anti-knock senser is not working properly I would need to check it to make sure it operating properly. If it is okay, your compression is to high causing heat in the cylinders for the amount of H2 mixed with the other gases.
The solution would be I think is to use less water in the charcoal mix. With less H20 the extra H2 is cut back to a proper percentage to stop the clatter or pinging in the engine. This should be adjusted for the seasons or outside air conditions of being to hot, or to much moisture outside. Every gasifier will be different because of the builders design.
It just comes down to the other 80% of gasification, the knowledge on how to run your gasifier.
Bob
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JO and Til, thats the thing. I never experianced this before! Allso what l noticed yesterday is if l use the hybrid mode a lot like driving uphill, the simptomes disapear. Its the worst when l drive for a few km on 100% char then try to hybrid. Lambda goes from 700mv (slightly rich chargas) to 0mv, power down, then slowly both power and voltage rise back to 300-700mv (stech).
Well in theory pressing on the petrol tb makes the same effect on the charges system as leting go the chargas throtle so it shuldnt effect a/f ratio?
I dubt dust can get in there… runing 100% char the petrol tb is sealed shut. In case of hybriding the chargas system is under more vacuum so when the petrol tb is open, the air will rather move down thain gas going back up.
Unfortunsly looking in there is about 3 hours of work, you need to get every pipe and fulel line dissconnected 
Rindert, ha, my problem is actualy reversed. I run great on chargas but have problems with petrol 
JOs words come to mind, woodgas being so much simpler thain petrol
Thirry and Bob, l just cant get this. In theory Hydrogen shuld be more resistant to autoignition thain most other gases??? Thus woodgas can be run in diesel engines with not too much compression just fine??
Here is what l think is happening. We have a engine ignition set for a mix of CO and H2, aka woodgas. Its a slow burning gas so we advance the timing. But if we increase hydrogen content we increase flame speed drasticaly becouse hydrogen has such a fast flame speed, even higher thain petrol. At this point the ignition shuld be retarded, if not, engine knock occurs. I think the timing is the problem mot the compression ignition of hydrogen.
Ok, some update. Pushing the limits Cleaned the filter and ashpit yesterday, topped the hopper this time with a mix of dry eggsize wood chunks and char, 50/50 this time, and went for a drive. Power good, idle good, and this morning not a trace of stickyness on the throtle was detected! This was a mixed drive, some open road some town trafic drive, with 2 30min stops.
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Is it possible you’ve developed an airleak somewhere downstream the AFM? On your “woodgas inlet rubber” maybe?
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But wuldnt the reading always be lean then?
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Yes, you’re right. As long as the leak doesn’t flex.
I think I would start with disconnecting the lambda completly, even if white wires are supposed to be heat only. Just to make sure it doesn’t mess with fuel pressure.
If that’s not the problem, look at any rubber hose or anywhere air could sneak in without passing the AFM.
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It seems to me that your computer and control system are taking too long to adjust. Is this possible?
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Hi all, this was a problem that had me scratching my head on my truck. A rubber coupling fitting that was some times leaking but not all the time. It would vibrate loose at low vaccum causing a lean condition and then seal up and would be fine again. The clamp was tight to turn it, but not tight on the rubber connection to plastic pipe. Replace plastic pipe, rubber coupling, and screw clap connectors. Problems solved on that intermittent leaking causing weak gas. I also rewired the pipe up like Wayne had it wired up. The bailing wire had loosen up from road driving vibrations.
I know this is a little different from what Kristijan’s problem sounds like, but it was so simple to fix and hard to find.
Bob
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And less smelly! Started working on the old Land-Rover to bring it back to life. Had to dismount the carburetor as it was leaking a bit.
Puuh, smell of old petrol for hours… Looking forward to get rid of this!
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Go Til, the smell of a new build on the DOW site. This is going to be a awesome build. I can feel it.
Edit: If you have not started a Land-Rover Gasifier build thread yet, start one up and show us what you are doing on your Land-Rover to get it ready for your gasifier build.
Bob
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what Bob said i second, and what you said about clean burning wood gasified vehicals, i second that too, with my old chevy v8 truck and a WK gasifier i could lay under truck and face the exoust with verry little resistance, though of coarse there is some emmissions. It felt much cleaner than petro fuel.
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This great news Kristijan, as soon as the weather warms up I want to start on a built like yours, the more things you get work out on the build the easyier it will be for anyone to build a gasifier like yours. I have always worried about brands in my cross flow gasifier making tar and taring up a engine, but you are showing all of us it can be done with out any tar production if it is set up correctly in the gasifier and filtering, with the right mix of fuel, and water.
Good Job Kristijan, keep it up showing us all that there are still new discoveries to be found in the world of gasification.
Bob
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Well, there is not much to show yet, but I will do it. That will keep a slight pressure to me to progress
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Tilman; Just start with some pictures of the Land Rover as it is today, include the engine compartment and maybe the under carriage. TomC
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Yes, what Tom said, it is great to see the very beginnings of a gasifier build.
Bob
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