It sounds a little tricky, but I get that it would be running on the propane, with wood gas there too, and then transitioning to only wood gas. I can’t imagine it not working. Thanks Matt
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It will be interesting to see how you do with Propane. You can basically cut it right off right? Might even easier.
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There is no valve on the propane from the regulator going into the carb, but there is the valve on the propane tank before the regulator which I can use to cut off the propane. I’ll let you know what happens.
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Greg, I have a hard time visualizing verbal descriptions, so here are some photos which show my set-up. I got the idea from photos showing Gary Gilmore’s set-up for his log splitter. The first photo shows the overall setup. The second one is a close up of the carburetor area, and the third shows the change in the setup when ready to start and run the engine—the blower is removed, air mixture valve adjusted, and the engine air filter put in place. I usually wait to screw the air filter on after the engine is running. I may be rushing unnecessarily, but I’m usually pretty quick moving to the setup in the third photo once the flare stays lit, before pulling the rope. I don’t think I mentioned it, but it helps if the air mixture valve is close to the carburetor as well. It doesn’t always start on the first pull, but most of the time it does.
I expect the length of your gas line is a problem. The line going to my Toyota carburetor is 18 feet long, but with the blower sucking the gas right across the top of the carburetor, the engine starts almost instantly. Of course in that case there is an electric starter. It can be exhausting trying to rope start a wood-gas engine. Once you get your procedure/technique down, it’s not so bad.
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10 feet is quite a bit of hose - you could probably get it to go if you had enough patience, but it will probably be easier to reconfigure it. Steve’s setup looks pretty slick, and I will say that it feels awfully good to get an engine to fire on one pull, especially if you are demonstrating it for a wood-gas skeptic! I feel like on my setup it takes me 2 or 3 pulls to clear a 2 foot section of 1" pipe (on a similar displacement engine).
Looking forward to seeing it up and running!
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I generally push the gas to the engine when in flare mode. I do not use a shut off valve going to engine, you simply shut off the intake mixer valve and I have a small drain hole in the engine adaptor. By the time its ready to flare good gas is already at the engine and they fire right up. On my latest build I am moving the draft blower remotely over the mixer on board the engine. So in order to draft the gasifier at start up the connection hose will need to be hooked up and the blower will be powered from the genny’s battery. So now the gas will already be there at the engine when ready to fire up. 
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Steve, can you give us a link to the video you watched? I cant find it.
Rindert
Rindert,
I used to have it bookmarked, but have since deleted it. After some searching, I found it for you. Here it is: https://www.youtube.com/watch?v=gUvWlFtdx9E
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I got a little further today. It spluttered for maybe 15 seconds. The routine in this video happened several times. I found a sweet spot with the air valve - At least I found a spot where it was worst above and below it. But it wasn’t sweet enough. It just spluttered. It was like you wanted to nudge the gas pedal, but there is no gas pedal, just the air adjustment.
I thought old charcoal or ashes might be plugging up the system. After the previous session, I just let it suffocate itself to go out, so there was a lot of charcoal left in it when I started, and I didn’t check what it was like in the reduction tube. Maybe clogged up? I’ll check before the next run.
My charcoal size was 1/8" up to 7/8", but maybe I should try 1/8" up to 1/2" next time?
Maybe this little engine can’t provide enough suction for fast enough air speed, even with the six nozzles reduced to 19/64" diameter.
Maybe the gas would work better if it went into the carb through the port where the propane goes, rather than being mixed with the air first and going in with the air.
I really appreciate your ideas, especially Dave’s suggestion to use my drill instead of pulling the rope!
Steve, I am pushing the gas to the generator (rather than pulling it as you do). So in my case, the engine has to suck the gas through the blower, which maybe is too much resistance, but I didn’t think that would be a big deal. Is it?
Carl, I have considerably reduced the length of the hose, from 11 feet down to about 4 feet. Seems to have helped a lot.
The whole gasifier is quite massive and it takes a long time to get hot. Like last time, it got up to about 600°C at a point just after the reduction tube, but it took about 2 hours. How long after lighting up should you wait to start your engine?
Despite all the problems, it was nice to hear it splutter for the first time - At least there is some hope!
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Hi Greg , first off that was not a splutter that was a running engine ,be it only a matter of seconds it did run on its own ,so you are close as close can be well done !.
Looking at your mixer valve it looks to me as if it is almost closed , i understand what others have said about start with it almost closed and gradualy open it till you hit the sweet spot , but if that is as you say your sweet spot , then before you change or alter a single thing , please get a spray bottle with soapy water in it and with a blower blowing down through your gasifier and through your filter and pipe work all the way down too the carb start spraying the soapy water looking for tiny bubbles along the joints seals and pipework , in my eyes that looked a lot like very weak gas , but i could be wrong .
Dave
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2 hours does seem like a long time. Is it possible you need a bigger blower or suction fan? I also agree with Dave regarding looking for leaks.
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I am having problems with “weak” gas also. My plan for today is to start the gasifier going. Then disconnect the pipe at the carburetor and cap it with a plastic bag and rubber band. Then get a plug that will fit tight in my air intake port. Then run my blower so that it pressurizes the hopper and see where any smoke comes out.
Also, that ball valve you have at your air mixer seems a little large. All you have to do is move it just a “hair” and it make a fairly large change in the mix. A smaller valve allows you to bump the valve a 'hair" and you get less change in the mix. TomC
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I agree with Dave - check everything for air leaks - then test it again. Keep making 1 change as you go, so you can narrow down what it was that wasnt working. I doubt pulling through the blower fan should be a problem, but it might very well be where some air is getting in, depending on what you are using and how its plumbed. If you make the blower into a stand-alone unit you can pull gas all the way to the end of your hose - regardless of how long that is - and then just move the tube over to your carb port. Also makes it easy to swap to different engines from one gasifier.
I would also give some thought to getting a fresh batch of charcoal that has been graded down to what will pass a 1/2" screen. I say fresh, because I had a huge hassle with charcoal that contained too much water that it had soaked up from the air. You will also get a bunch of condensation in your pipes and filter and such - so it should be pretty obvious if that is the problem.
Cleaning out the reactor after each lengthy run is also good practice, because ash or slag building up will inevitably cause you problems.
You are almost there!
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All great advice’s.
Greg blower delivery should not be a problem. IF it was a larger drawing engine then maybe that small blower would cause flow supply restriction.
Piping/joints leakage from the blower to the engine (until the engine is strongly running - sucking) could cause an engine sttaring problem by too much fuel gas loss, and flow delivery loss.
So, yes do need to check that plumbing.
Matt Ryder put up an Argos picture of Gary Gillmore’s charcoal gasifier-system-on-a-handtruck, producing, supplying an generator set to recharge a Tesla car.
Look at his blower. Wanna bet it can out-volumn the one you are using by 3X, 4X?? But at a 4X, 5X; 115 vac higher watts input? Maybe as pictured it actually is a handcranked forge blower? Still be 2X, 3X the now armstrong input power watts you are using now.
The blower Ben supplies was selected for standalone off-grid use from just a single 12 vdc storage battery.
You want faster warming up go the Mike LaRosa/Tom Collins/Dutch John way and use a high speed 115vac vacuum; power supplied by a large 12 vdc battery through a 2000 watt DC-to-AC inverter.
Careful. Ben’s blower could normal auto/small boat sized 12 vdc battery run for as you’ve found run for hours and hours.
Up watts demand from the same sized battery and you will only have battery capacity for minutes; certainly under an hour.
Truly. There are no free lunch in Life. No free energy. And certainly no cheap energy that has not been derived by some form of outside inputted energy-stealing slavery.
Everything is a trade-off; pros and cons; decisions. The mistake is step-point idealizing.
Regards
Steve unruh
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Greg I forgot to mention that because yours is a downdraft gasifier i am sure that the size of the charcoal is not a major issue nor is dampness ,its only we who have updraft suffer from those problems .
Kristijan soaked his charcoal to give his downdraft some extra power if memory is correct .
Dave
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Dave, Yes, I have found lots of leaks. I am in the process of fixing them. I’m sure it will make a difference. It will be a day or two.
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Bill, I’ll try it with the leaks fixed first and move on the a better blower if that fails to get it started.
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Hi Tom, Yes, I’ll keep in mind a smaller valve for more accurate adjustments. I’m finding all sorts of leaks with the pressurization.
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Carl, It seems you disagree with Dave about the size and moisture content of the charcoal. Or are you talking about an updraft gasifier?
I’ll get the leaks done first, then try to form my own opinion about the size and moisture content.
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Steve Unruh, Thanks for the tip about running a stronger blower from an inverter. If I get to that, I’ll be careful it doesn’t drain the battery too fast. The 12 volt blower did seem to run steady for a couple of hours.
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