My gasifier keeps firing back into the hopper

Hi all im new here and apologise if this had been covered, i sesrched forum and couldnd find an answer.

My issue is that my gasifier keeps burning back into the hopper and blowing off the hopper top. What and i doing wrong.

Any help is appreciated.

I built the same style as Flash001 that i found on you tube

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Sounds like an air leak without knowing much else. The only reason it would backfire is oxygen mixing with the gas.

Take your blower and push air into the whole system and spray soapy water on all your welds and threaded points. I’ve found with threaded spots it’s good to put on some lithium grease(if it doesn’t get hot) or graphite grease(if it gets hot) on the threads. Helps seal it up and make it easier to remove for maintenance.

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So air leak into the hopper? I thought maybe my nozzle wasnt deep enough.

Seems like as soon as it gets hot enough the smoke starts going back into hopper and once i reach temp to crack n make gas it fires back up into the hopper tube.

I was gonna try and add an inch and put the nozzle further down towrd shaker grate, or would tjat be a lot of work for nothing?

It

The air nozzle is like 1.5" down past that lip

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Also this thing sealed up tight as anythi g i rtv the hell out of everything and the welds too😂

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I noticed smoke building up in hopper too😬

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Smoke building up in the hopper is normal, that’s the wood pyrolizing.

For air leaks what I mean is all the other gas routing. Air could be meeting anywhere in the system.

Are you running it with the lid like Flash uses or without a lid?

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Had a lid on it till it blew off​:grimacing::joy:

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I noticed with my little single nozzle gasifier, if I used a suction blower and tried to light a flare, the flame would light pretty quick and then go back into the tube and poof the lid.

You might have pinholes in your hopper. I’d still check with soapy water. Anywhere you suspect a leak first.

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Im not routing it more than througj the first cyclone filter chamber and then igniting just for test

Forgive the crudness of my work everything used was free so had to oiece together somehow

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Is it cause my lid wasnt sealed well enough perhaps?

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That could be the case. Does it have a gasket of any kind?

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The first time i had it together it was sealed well, but then the gasifier burped and blew it off

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It could also be the barrel lid having a bad gasket. You can make one with fiberglass stove rope and red RTV. Put the rope in a plastic bag and squirt two of the toothpaste sized tubes of red RTV and massage it into the rope, then lay a bead of RTV in the channel of the lid and put the rope in the channel. Also put some saran cling wrap on the rim of the barrel. Clamp it down while it’s drying to make it form the shape.

Rope size don’t go bigger than 5/8" diameter fiberglass rope.

When it’s dried take the cling wrap off.

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So its not happening when i lght a flare off the tube, i o ly got that to happen a few times but, its happening before i get to that point at times, in the fire tube and teaveli g back up into the hopper

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Do you have an ash cleanout like Flash had?

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This ia how i made the gasket with rtv and fire rope👍 ty for sharing that it makes me feel cinfident its not the lid

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I do, it also is sealed up with rtv

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I’d still do a bubble test. It has to be an air leak somewhere. Put the lid back on over the fire tube area with some spring pressure, and blow air through the air entrance that goes to the nozzle. Or blow in reverse at the cyclone since you said you’re trying to light from there.

With the blower in reverse you’ll get a little leaking at the lid, but if it’s really leaking you’ll know. What most guys do when they go to refill the gasifier or start it up they’ll get it lit and then run it in reverse to push all the oxygen out.

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Hmmm. You pictures only show one 12vdc bilge type blower?
Those are very low sucking capability.
Stack up three and try again. This is what Canadian Dean Lasko is doing.
Then you’ll keep up a draw through your upper end. Should help keep you from having the hopper Poof’s.
IF you are having too much air leakage you will then be burning up your charcoal with non-combustible gas output.
S.U.

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Welcome to the site, I’m new here also and just built an imbert type gasifier, looking at your pics I see your nozzle does a 90 and heads outside barrel, and in you next pic it shows a pipe going to red tank and to blower, so is this a updraft type and your nozzle intake is on other side of barrel we can’t see? Or is your nozzle hooked to the pipe we see? I’ll have to check out the flash videos.

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