The thing about updraft Charcoal C, is that the hopper full of charcoal fuel acts as a preliminary filter. I don’t think I’ve heard anyone report gumming up an engine with one.
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You have to make sure the charcoal is converted entirely of course. It’s second nature to anyone that’s messed with charcoal gasifiers but isn’t always mentioned.
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Tom, l have. The thing is, runing a small engine occasionaly, you burn maybee a few tens, hundred of pounds at most per year. Statistic probability of geting something nasty mixed in with the char is low, and also chances are you take great care to make clean fuel. Driving a full time vehicle every day, burning trugh tens of pounds a week, sooner or later you WILL step on a landmine. Kids throw a bit of sawdust in the charcoal, you get a britle brand that you dont notice… and it only takes one such event to get you a sticky throtle. But it is true that usualy thats about the worse that it gets.
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But if you build the charcoal gasifier to handle that little bit of brands ,sawdust, or just plan old wood and still not make tar because of the design features like a hopper that can remove moisture, with tars gases and collect them this will greatly impove with ever getting a sticky throttle or valves.
Bob
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So it seems if I leave the charcoal sitting in the hopper for extended periods of time, it absorbs moisture. When i flare to test if its ready for an engine, I see a moisture cone. I can hook it up to an engine and the engine will run. I haven’t ran for extended periods of time. I usually fire it up to show people how it works.
What i have been experiencing is the governor butterfly will freeze up to a point where it can’t be loosened up. Do i need to run it longer or run it on gasoline for a period of time on gasoline to prevent this from happening?
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I am not a chemist but I notice an ammonia smell in the charcoal gas when running and I think that has something to do with the butterflies seizing up where the shaft goes through the pot metal or whatever the carb body is made of. I spray a couple of squirts of liquid wrench at shutdown to lube it and work it back and forth to coat the shaft.
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Thanks Don. I’ll try that next time. I did buy an extra carburetor to have a new one on the shelf. Is there something I can soai the seized up carburetor in? Maybe diesel fuel?
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If it’s a rusty kind of seizing I’d try vinegar for a day or two.
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Hey Bill, Try warming the carb a little while spraying, and working the throttle shaft. Heat gun(be careful not too much) or hair dryer.
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I don’t know if this will help, Bill. Interesting anyway.
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Nice video, but not relevant to cleaning crudded up carburetors or throttle bodies.
Working in diffnert dealership shops: Toyota; Chrysler/Dodge/Jeep; Nissan; Saturn; Buick-Oldmobile I had to use only their branded, manufactured products. The best by far was a Chrysler Combustion Cleaner spray (a decarbonizer to be used sprayed down into on hot warmed up engines and left sat for 2 - 2.5 hours.)
P/n 04318001 AD/AE
Look it up internet for many sources including Amazon. ~$11.00 USD
Carburetors and throttle body almost always have rubber neoprene, teflon, viton part in them.
Throttle bodies with sensors and actuators installed. Most effective cleaners will kill these if immersed. Left, gross dripping wet sprayed on “soaking” overnight.
I/we found using this Chrysler spray instead as a cold spray with cotton swabs and plastic tooth brushes worked the best for TB and Idle pintles cleaning.
Yes I have used it on gunked up sticky/stuck woodgased carburetors.
Long-wand SeaFoam spray is a far second effective and works too.
Some really good specialty products out there too. Like From BG.
Just keep in mind the carbons and soots are NOT disappeared. They are loosened and washed/floated moved somewhere. But NOT away. Using cotton tipped swabs and changing out often takes them safe, away!
Carb/T.B. off then you can let it drip clear. Even air nozzle blow clear.
Carb/T.B. engine installed and all your cleaned clear gunk and chemical cleaner goes into the intake, and then into the the engine past the intake valves. Real easy to wash through enough to foul out and have to replace spark plugs.
Real easy to kill TB or intake mounted sensor.
My 1994 Ford pick up 5.0L V-8 has a dual throat vertical shaft T.B. with coolant warming lines to it. The throttle position sensor is at the lowest point on that vertical shaft, mounted.
So I’ve cleaned it once after a woodgasing attempt by removing the TB to hold that sensor UP.
Normal gasoline driving I’ve carefully spray wetted Q-tips and cleaned it in place. it is Ford stickered, Special Coating - DO NOT CLEAN. Yeah, right. Dirty hanging open needs to be cleaned.
Ha! Ha! For piston on rods cleaning I’ve used many times gallon buckets of the commercial carburetor dip cleaner. Cleans and slick then right up after 1-3 days. It stinks terribly. Is extremely caustic and toxic.
It WILL kill all soft plastics and seals.
I would have bet before hand with the video set up on the white vinegar. No way in hell I am putting that down an engine throat!!
S.U.
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Late on line today and just read Bills post , i have had these issues for near on 10 years now , i have left engines for months sitting and found that the butterfly’s on the throttle are seized rock solid ,if that happens the easiest way i found was to take the float bowl off and look at the casting where the pin for the throttle is you will see it protrudes down a little ,so i drill a small hole just smaller than the dia of the pin that holds the butterfly , then using a punch i tap the pin back and forth till there is movement enough to start turning the butterfly to remove the 2 small screws in it to take the butterfly out and then remove the pin fully use some wet and dry paper to smooth the pin from the corrosion and then smear with high temp grease and re install .
Now when i stop the engines i always give it a spray of WD40 when slowing down and about a day or 2 later if i remember go give it another quick squirt so far been good for a few years now .
Dave
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Don, l too notice this but even thugh l am a chemist, l can not explain it. The mechanism of how ammonia can be produced in the athmosphere of a gasifier make no sence to me. Hydrogen and nitrogen do get turned in to ammonia in contact with iron (Haber-Bosch reaction) but at wery high pressures and temperatures.
Whats interesting is cant detect the smell in woodgas. Ok, maybee tar traces mask the smell. But l cant detect the smell in a downdraft charcoal gasifier gas neither! But l can smell it again when l open the hopper.
This all leads me to belive that whatever makes ammonia must only happen in conditions like in an updraft. Meybe the ammonia is produced by gases reacting in the charcoal bits them selves and get released by heat? Who knows. All l know is that the downdraft gets rid of it and thats just one more bennefit of going the extra mile when building.
Anyways, aluminium and zinc both corode in basic enviroments and if there is indeed ammonia in the gas, that wuld make it wery basic. Probably why brass throtle plates become britle too (@JO_Olsson knows about that) zinc gets eaten out of the alloy.
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It seems the Rabbit throttle plates were made of a very cheap alloy. The Mazda and Volvo plates are brass too, but still looks like new. Only the screws holding them rust some (also the pot metal tb’s themselfs get worn internally over time of course).
About the ammonia smell - I find soot and water in coolers and hayfilters to smell like a stable. All downdrafts. My thinking has always been ammonia.
What Don said - I’m no chemist - but by experience I sometimes find the smell of methane close to ammonia. If there’s no ammonia produced in a downdraft - could methane be what makes the hayfilter soot smell?
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JO, I agree about the methane smell, I smell it in my hopper and in my hayfilter sometimes. Next time I smell it I think I will compare it with a bottle of ammonia. I will let someone else smell the ammonia in a bottle and I will smell what’s in my gasififer. Then we can compare notes. Smile and grin.
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I consider the smell a blessing, since CO is normally scentless.
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It’s possible that Nitrogen compounds (Nitrates) are getting converted to small amounts of ammonia.
There is work to do this deliberately with catalysts which include iron, copper and nickel to varying degrees. It wouldn’t surprise me if a little ammonia got into the gas stream given how often those metals would be in use, especially stainless parts. Ammonia is also easily absorbed by water so it would tend to linger in a cooler or hay filter and be smelly there.
Alternatively it could be the nitrates themselves which are more rotten egg than ammonia but maybe a mix of smells including nitrates smells like ammonia? Hard to say for sure.
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The Ammonia smell seems to only happen to me after a run that produced very wet gas , i had a filter that had stood for a while after a run maybe over a week before i decided to clean it out and the smell was so strong i had to walk away and leave it open to let the fresh air take care of it for me .
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I wonder if the ammonia odor is biological. This would seem possible in a hay filter especially. Can any of you describe the smell of methane? I thought is was supposed to be odorless. Is there some other compound produced with the methane than gives the odor? The methane in biogas certainly has plenty of aromatic compounds mixed in. Aromatic in the sense of aroma, not necessarily in the organic chemistry sense.
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Kent, the methane smell was more of a bad fart joke from my part 
Wether the ammonia is made in the gasifier or in the hayfilter’s wet enviroment, I don’t know. But the condensation sure smells like it.
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