I’ll have to check it and get back to you Paul Until I get there, what are you thinking Paul? TomC
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just fishing for more data ruling out where the restriction could be I just came back from a burn tube failure internals went crazy.
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Just to clarify Tom you’re measuring grate vacuum ? Not the hopper?
There should be almost no difference between the grate and rails.
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I am with Chris .
Yes if you are measuring the vacuum post grate and the cooling rails they should be almost the same
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Sorry to say, I’m not running a WK. My vacuum reading are one on the cooling rails and one out of the grate area, which a Chris says should be equal but I have always found the rail was about double the grate. ( ? ) I let the ash pit get totally full — with only 4+ inches from the nozzles to the restriction, I am hesitant about pulling all the ash out and upsetting my char bed. I did however empty the ash pit and not much changed. So I took a rod and reached in and cleaned some of the ash/char off the grate and rodded the grate out from the top. It helped the driving, but still pulling more vacuum than I had been . Oh something else, While starting up cold, it blew a little smoke and then went to a very faint smoke and the temperature was very slow building up. I usually get the grate temp up to 900 before I feed it to the engine. I never got over 700 and I was able run on the gas so I went for a ride. That is when the temp kept climbing to 1800. That scared me. Something was wrong on start up but I hope running up to that temp didn’t warp my restrictor. TomC
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Oh hey! Just a thought in getting ready for the trip I cleaned out my hay filter. Of course I have kind of an odd hay filter. Basically it is hay with a 4 inch piece of foam on top before the gas exits on its way to the engine. Besides changing the hay I probably did something dumb. I put the foam in a tub of water and using a garden hoe pumped the foam to wash the soot out. Then I had this HEAVY foam full of water that I couldn’t hand squeeze out by hand. I put it on the garage floor and put a steel plate over it and drove the tire of the truck onto the plate. Long and short of it, I got “most” of the water out and I blew through it with air and set it aside for a day. When I put it in it was almost back to the weigh of new but did have some most feel to it. Did that cause my restriction???TomC
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Second thought I doubt if that would cause a high vacuum in the rails and ash pit. TomC I’m going nuts trying to figure this out
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How did it run? Was it acting weak, like there wasn’t enough gas?
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At times like this I find it helpful to go back to the basics. we know that to have a vacuum in a container we must pull out more air than we let in. So If your vacuum reading is higher You MUST be either sucking harder or not letting as much in.
For sucking harder, Maybe your kirby is running faster than you usually run it, or if drawing with the engine running, your air mixer is closed more than normal or a restriction in that area.
As for letting less in, it would have to be a restriction somewhere on the inlet side. Plumbing, nozzles, char bed.
I suspect that if you punched a hole all the way through the char bed , it would be letting air through and burning you gas post grate accounting for the high temps.
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Yes Chris, it did feel weak.
Andy I am letting it cool down over night and then I will get in and remove and wood so I can see what is happening between the nozzles, restriction, and grate. I have some fears about what could have happened, like when probing the grate before firing it up, maybe I hooked the restrictor and pulled it off center. I don’t know— chapter 2 in the saga tomorrow. In the mean time if something comes to mind let me know
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Sorry, we were already asleep across the pond.
Try Pauls suggestion: Check vacum readings with the lid open before you mess with your charbed. That would rule out any air inlet/nozzle plugging.
You say you have high grate area vacum and a normal 2 to 1 across your cyclone. If air supply to the nozzles is OK we’re then left with the charbed.
You say you suspect your restriction insert is tilting letting gases bypass more easily. Wouldn’t that lower both vacum and temps?
Your high temps on the other hand has to be another problem, like Chis says. Seems to me indication of oxygene present in the grate area. Loose charbed (overpull symptome) caused possibly by wood moisture issues, as Wayne pointed out, or an ash pit air leak.
My newbie 2c
JO
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Hi, Tom!
Emptying the cyclone? Pressure measuring before to after the cyclone?
If you don’t keep your ashpit reasonably empty, you will overfill your cyclone real fast!
Then, it sounds that you do not have open cell foam. Open cell foam is easily rid of collected water…
Max
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Thank you for you help everyone. J. O. and Paul it probably is to late for and open lid test. Last night I was in there digging down in the charbed trying to see anything I could. I had run my wood down to almost the nozzles. Max, you are absolutely correct about getting a lot of soot out of the cyclone when the ash pit is full. Recently I changed the soot collector on the cyclone to a glass jar, and am amazed at how fast it was filling up.
As soon as I get back from the doctors I am going to dawn my old cloths and get into the reactor. Sitting in the house is definitely not going to solve the problem. Thank all again. TomC
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Hi, Tom!
16.05.2016
Hopefully the doctors don’t restrict your activity!
I meant, that the cyclone could be filled all the way up to the outlet, not only the collecting jar or bucket!
That would give a real pressure drop! And as you have talked about a pressure drop between the ashpit and your cooler, this would fit in!
A cyclone after an ashpit is always at risk to be jammed by soot, ash and charbits! It takes dayly checking to avoid that.
Max
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A Wobig “family” made personalized coffee cup is a rare and valuable thing.
Still got mine.
Thanks
S.U.
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Hi Tom,
Hope your Dr appt went well and we see you at Argos. My dad had a saying- “Getting old aint for sissys”. So true!
Regarding your gasifier problem: While I know little about gasifiers, I’ll throw in my 2 cents worth. If I was a betting man I’d bet your problem is something simple. (Yeah, that helps a lot!). You’ve mentioned the high vacuum readings which point to a restriction somewhere. The high gas temps might appear to be a separate problem but maybe not. I think Tom Ws analysis is close. While you don’t have time to tear the whole gasifier apart I think you can narrow the problem down. Can you drill some vacuum ports into the hopper and several points along the air inlet portion of your inlet air heat exchanger? This would show you exactly where the restriction is and you could troubleshoot from there. I would also do a quick check on your vacuum gauges by swapping the lines to them to make sure they are reading correctly.
Hope this helps. Keep us posted. We’re all learning from this.
Kevin from Suamico.
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Tom,
One thing you mentioned to me last Saturday was that your inlet air temps were lower than normal. I don’t recall you mentioning that on the forum, but correct me if I’m wrong. That fact might be helpful to others also.
Kevin from Suamico.
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Hi, Tom!
18.05.2016
Cyclone once more…
The inlet to the cyclone seems to be high and flattened as the side-photo reveales…
This gives the possibility to plug the inlet, even if not much is collected in the bottom jar!
As the flattening does not pass as big bits of char as the rising tube, it can start collecting other bits, as soon as one bit is stuck in that passage!
Max
Thanks Max I stripped the gasifier down to the cyclone yesterday and kind of sorry to say, Every thing looked clear.
Two days ago, I cleaned out the char and inspected everything. A few items came up but nothing dramatic. I sifted the char/ash and dumped it back into the gasifier. Tried to get it running and it was not making any smoke from the Kirby dispite having a hopper full of brown smoke ( I had added wood by this time) It flared The engine fire up so I took off down the road. In a very short time I hear a big kaboom and the engine die. The top of my hay filter blew off and the foam was sticking out half way… OK!!! We see the problem, the foam is p;urged. Found the lid and put it back on without the foam. No better. I pulled all the hay out and the vacuum was still high and the grate was back up to 1500 degrees F.
The fact that I didn’t get “smoke” out of the Kirby really bothered me. Yesterday I took the cyclone off and inspected it and flushed the cooling rails, and took the hay filter apart ( not there is much to it with no hay in it.) Was putting it back together when I ran out of gas yesterday.
Thanks for the help TomC
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Get it to Argos by hook or by crook… we’ll get you running right! 
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