Hi, Thierry!
9.9.2016
I had propopsed a silo-bottom conical funnel made in two parts; the upper part having a slope of 45 degrees to the horizontal plane, and the lower part connected to it, having a slope of 65 degrees to the horizontal plane. OK?
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Hi, Tom
9.9.2016
Pepe has done that repeatedly, successfully!
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Yes Don, That looks very doable. I was thinking Kristijan was talking about square mesh. I like the rod idea of Pepe. It will drain and the wood will probably slide easier on the rods than even a flat plate metal. TomC
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Kristijan,
Your brother is someone you can pass your charcoal-gas knowledge on to, and with the price of liquid fuel remaining high, his motivation is strong! 
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Kristijan!
I’m not very patient 
I understand you’re back home. How did your DOW weekend trip go?
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JO,
lm finaly home yes 
we had a great trip!
A short rewew; l cleaned all the system, packed it full of 4 year old oak chunks and away we went. At the first hopper we drove great. Near gasoline power, good acceleration. Cruised at 60mph no problem. Thain the engine pulled weaker and weaker… and the last half of the drive was in hybrid mode. After a nice family afternoon at my fathers place l emptyed the gasifier only to find the reduction FULL of ash/chardust. I realised my mistake. The fact of woodgas being a slow burning fuel set my mind to drive at low rpm, in the 2100 range. There just wasnt enough gas flow to draw the dust out. The way back l lowered my drive a gear so we drove in a 2600rpm range. What a difference! Only swiched on hybrid at crossroads. Will open it up agen tomorow to see whats up now.
Anyway, we all love pics 
The gasoline on/off and hybrid mode swiches-the only real modification to the car
The gasifier and hot filter
gas hose
Allso a few from the trip:
The refueling stop. The future Seat owner on the left
A few of manny oldtimer motorcycles from the mountain race. This last one kicked ass. Both wheals are driven and the drivers were a bit crazy
in the next second l was faceing an meteor shower from the gravel they torn out of the road.
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Wonderful pictures, Kristijan! Our wait payed off 
Edit: Shorten the reduction just an inch and you can lurk around the village at 1000 rpm.
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Wow!!! Been a long time since I watch side hack racing. Those guys are crazy In the turns the rider sometimes has his head almost on the ground. Exciting but crazy.
Your gasified car is amazing. Your first wood gas build and it works so well for you. You must have been re-incarnated from the 1940’s when woodgas was growing in EU. You seem to have a much better understanding of woodgas than many of us old timers on here have. Congratulations on your first trip TomC
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JO,
You are right. The reduction is most likely to big. The grate is now at allmost 5" from restriction. You are at 4" if l remember right?
Tom l dont know about that reincarnation but l did caught the wood gas feaver some time ago still have a lot to do on the build, and a whole lot to learn!
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Yesterday when l drove to work, the settup dyed completely. Wuldnt eaven run on hybrid. Like there wuld be no gas at all.
Drove home on gasoline and emptyed the gasifier. The char bed was good size (l used beech this time, no oak) but at the reduction there was a lot of soft slag/powder.
I am at close to 5" grate below restriction top now. How far do you guys think l shuld lift the grate for better ash outflow? Or shuld l use bigger fuel? I now use about 1,5" fuel.
But that wasnt all… l then poured some water in to the cooler/filter. It came out on the bottom. One of the coolingplates was cracked and 3 bad seals made of thick leather were the reasons for that. I got a thick rubber now and a new cooling plate to install in today. Hopefully that is all…
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Hi, Kristijan!
14.9.2016
I deplore the cracking!
If you can put up some pictures of the broken spots, some methodes may be found…
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The crack was most likely my fault. When installing the gasifier on the platform l must of have hit the thin aluminium plate on the syde, pokeing a hole in. The bad seals were leather shrinked to point it let air in. Rubber shuld fix that.
The only thing l havent figure out is grate position. Did some reding and calculateing and found out the oxidation part shuld be of good lmbert dimensions for the 1.6l at 2500rpm engine, it holds 1.2l, but the reduction holds about 0.5l all calculated in cone shape. Any thods?
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You already know my suggestion. One inch up and slightly bigger fuel. Egg size or 2".
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Hi, Kristijan!
14.9.2016
1,6 X 2,5 x 3 = 12 l/s … gas consumtion
12 l X 0,07 = 0,84 l … Oxidation volume if fuel size =
~ 1/2 cigarett pack size.
Truncated cone form with 60 degree slope.
Restriction … d = 87,4 mm ~2,0 m/s
Nozzle tip circle … d = 160 mm ~0,6 m/s
Hight … 68 mm
Volume … 840,676 cm3
Common nozzle tip area… 3,6 cm2 ~20 m/s
3,6 cm2 : 7 = 0,5142857cm2 ~d = 0,81cm ; d = 8 mm
All flows = cold & empty!
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Max,
thank you for that detailed calculation!
Looks like oxidation zone is a bit to big. The other things are as you calculated.
l fixed the airleaks and moved the grate just short of an inch up. Hope this will never happen agen
Took a picture of the hopper
It now runs much stronger. high idled about an hour to dry the seals, thain l performed a short drive test. The first looks are promissing, will see what happens tomorow.
And by the way… The red 300c silicone didnt last on the cyclone. A nother leak. Tryed black this time.
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Hi, Kristijan!
15.9.2016
“Looks like oxidation zone is a bit to big.”
Just about 43% too big concidering the fuel size.
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Max,
There isnt much l culd do about that, exept build a new gasifier. Hope it will drive well now.
First observations after a longer drive: the drive is a totaly different thing now. I have to change the air valve a lot more. The system allso runs a bit hotter (most likely becouse cold air no linger mixes with the hot gas in the cooler) but the performance is good. I just hope the ash plugging is gone.
There is something wrong with the idle servo. It cant catch a steady idle eaven on gasoline. As if its too slow. When l stop for a trafficlight l had to stop with a handbrake and let the rpm fall slowly with my gas pedal. If l jjust let it go the engine dies. I think l will install a screw on the throttle body to manualy adrust the idle.
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One more topic l wuld like the opinion of you guys on… l have a small volume sistem. I get the gas from the gasifier to engine in about 3 seconds. This means at an idle l have very rich gas and at takeoff a lean one. Not just a long idle, a few seconds stop and l see the change in gas quality. Same is at acceleration or basicly always when gas demand changes. There is a hole in performance of about 5-15s everytime gas demand changes. This is unacceptible for me.
Althugh l have no dubt a membrane automixer works well for a system that has gas reserve to mix and smoothen those peaks, like Chris and others, l am starting to dubt it is an optimal solution for my build.
Has anyone got experiances with electronic gas mixers?
The way l thod l wuld get things done is by a lambda (o2) sensor on the engine exhaust. As l understand the lambda shows 0.45v on ideal air/ruel mix. So if l culd find a way to connect the air intake valve with a servo motor or an install a electromagnetic valve with a positioner, to hold the lambda on 0.45v, this shuld be a much better solution. I know things might get complicated, but has anyone done it before?
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I recognize this behaviour. I think this is due to a slight over pressure for a couple of seconds until the char comes to rest.
High idle setting, or as you say, let rpm fall slowly. I find it usually helps just to leave the gear in while deaccelerating until the last second until stopping at the redlight.
This I don’t recognize. I can idle below 1000 rpm for several minutes and then suddenly accelerate and I don’t feel much difference in power from driving continiously. I wonder why this difference is? Somehow your charbed seems to cool down faster. Are you still at 3" restriction? That should be small enough. How did your preheat turn out? Do you think a higher idle is enough to keep it going?
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