Here is a post of the last run. It ran about 20 min. I was pretty pleased with it for first time run.
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I was surprised at the amount of moisture in the filter.
Im starting to make some new charcoal and hope to fire it up again this week end.
Joe
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Hey Joe , congrats on your run , if it is a flat head then Your Doing ok as they have lower compression than the more modern Chinese clones of around the same size , i have in the past run engines as small as 50cc but you do need to size the nozzle accordingly so that it keeps up the temp and makes strong gas .
With that wet /damp filter your showing in the photo i would recommend you maybe run some petrol through for 5 mins after shutting of the gasifier that should help dry out the carb and get rid of the fine dust that builds up around the butterfly .
Dave
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joe, what filter medium you use?
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Thanks Dave. I did mist the cylinder with WD40 after the run because i figured it will be awhile till i fire it up again. The gas idea is good. Thanks.
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My filter is according to Gary’s design. It is 4" of open cell foam then a thick piece of wool that is held away from the exit hole with a metal cage type thing. All of this in a 5 gal bucket. Ill try to get some pics posted.
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Hello JoeB
I suggest trying next on your filter reversing the foam and sheep’s? wood felting.
If it is actual sheep wool it will have a higher temperature resistance and be soapy water washable-reusable.
The open cell foam is common (cushions and mattress’s) so just trash it when loaded and replace. It will flows drain out the bottom. So make your outlet pipe up off the bottom. Have a captured condensate drain on the very bottom.
Regards
Steve Unruh
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I like it! Ill work to implement that. Im gonna look for a new bucket with a screw top also to make access easier.
Was wanting to make a new batch of coal but its raining and 50 mph wind gusts here. I think ill wait for a better day 
Kind regards, Joe
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Hi Joe , it is mainly the carb butterfly that needs cleaning not really the cylinder walls the moisture in the cooler area of the carb is what causes the fine soot to help seize the steel or brass butterfly pin to the aluminum/die cast body .
Dave
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Yea, makes sense. I’ll clean it next time at the end of run. For now I’ll spray carb inards with carb cleaner or wd40. Appreciate the tip. All these small details make a big differance.
J
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I fixed the link in the earlier post so you all can view the video. Here it is again.
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Kudos on stabilizing the mixer valve to the frame, your carburetor mounting studs will thank you! Thanks for sharing.
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Yea. It was great advice. thanks. I plan on bracing the exhaust pipe also. In the video you can see it vibrated loose and was bouncing around. J
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HI Joe, yep good steady running there , is it underload ? if so what are you drawing power wise ?
With all good intensions i would recommend placing a air filter onto your mixer valve asap , last thing you need is to kick up some of that dirt and dust around the machine other wise it will interfere with your fun.
Dave
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Nice build Joe! Thanks for sharing your project.
Maybe not relevant, but here are some thoughts on topics raised above:
Weak/poor charcoal:
Updraft designs are fairly insensitive to the weak charcoal issue. Size your course filter to match your run time and you are good to go.
One benefit of using poor charcoal is that it is often the most easily sourced. You can take wood that wouldn’t be useful for anything else and upgrade it to a useful fuel.
Run time:
I can get 8+ hours on very poor charcoal, an unmodified 212cc 3600rpm generator, and a 1kw load, using a 55 gallon drum updraft gasifier.
I’ve targeted long run times for convenience and to minimize other infrastructure (like battery banks).
My goal is “walk away, don’t worry about it for 8+ hours”, kind of reliability, and that is generally what I get.
The mixture changes throughout the run, rich while fresh reactive fuel is available, a middle value for the bulk of the run, and lean as it starts to burn out. Without active controls, you have to target the middle mixture value and accept the beginning and ending losses.
You need engine vibration to make the fuel flow regular and predictable.
You need to be aware of ash and slag and how they affect the gasifier breathing over a long run.
Some other thoughts:
A very hot reaction zone covers a multitude of gasifier sins, but maybe kills your nozzle.
Get to a reliable nozzle (flute, silicone carbide, tungsten carbide, ceramic, liquid cooled, ThriveOG) as soon as you can.
In fact, I’d say start there. The nozzles part 2 thread is very good.
Then you can afford to experiment with variables other than trying to keep your nozzle in one piece.
The chemistry of gasification is very temperature driven. When you cool your reaction zone to preserve your nozzle you get closer and closer to the edge; slow starting, picky on fuel size and quality, fussy mixture control, and confusing to troubleshoot.
A hot gasifier is a happy gasifier.
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Really useful information Chuck. I have never been able to run 8 hours unattended like you and Brian have but also haven’t really tried. As soon as I hear my engine change tone I generally run over and tweek the air valve so have never let it self correct. Everything got in the way of me testing out my Saw mill gasifier last fall with the water cooled slot nozzle. Hopefully before spring.
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Thanks Dave and Chuck. Sounds like good advice. I really want to get back on this project but I’m overwhelmed again with other stuff. I hope to get back to it after the holidays.
Joe
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Chuck, One question, can you elaborate on what you mean by sizing my coarse filter?
J
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Sorry Dave, I forgot to answer you. No real load. I did run a saw a bit during the run, just for fun.
J
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