Featured Project - Herb Hartman's 1991 Cadillac DeVille

Sorry for the rust Herb. I think setting around is hard on things and people. I guess that’s why SS is so good. Hope you get it going soon.

Yeah thanks Carl, I know you know about rust, my barrels didn’t have any holes in them though like yours did, mine was just where I used super thin metal and where it gets the hottest. If I remenber right your hopper went first! What’s your opinion on what made it do that, that’s different then what I experienced!
How is yours doing now after the rebuild and how are your thermocouples hanging in there?

Hi Herb, If corrosion is a problem, be it rust or acid, I see 3 answers. 1)Thicker material will last longer, thin ANYWHERE is problematic. I think the vibration of a “rumbling muffler” plus moisture (rust), contributed to the failure there. 2) Find, fix/remove the source, haven’t had much luck there, or 3) Go to SS. I’m still not sure why my wood hoppers are being eaten alive. Evidently more (concentrated) acid then most folks. My percentage of oak is way down now, but the hopper is still getting thin. The next one will be SS. Two sides of the lower gutter are already SS.

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Got the Caddy back together, put the char back in it, lite it and put about 10 gal of fuel in it. I let the fans pull air thru it for a while and lite the flair, took right off! Dicided to take it for a ride, started on gas and changed over to wood soon after that as usual. Took it outside of town a ways, turned around and went thru town and out the other way and on the way back in bout the time I was thinking this thing is running great it blow every pop-off on it! I switched over to gas and drove it home. This morning I checked things out and discovered it was out of fuel, it was bout 4ins. below nozzles!
Will that cause them to blow? Of course it’s still pulling in air and if there’s not enough wood I guess the air with the gas that’s in coolers and filters could explode! Suppose that’s what happened? Couldnt believe it was out of wood already although I know they will use more wood then normal first run!

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Glad you got her back together Herb. I can’t help you with your question. I have not started the other 75%:but I would guess that was the cause, lots of air space with no wood in the hopper and the mixture is right

Hi Herb,
That is an elegant looking caddy, showroom quality. That rear view shows an interesting configuration. I used line D imbert dimensions to build my stand alone unit. Two of your statements struck me as items I have just experienced. I’m starting to time my burns and taking temps in 4 locations and trying to find out when to add fuel. I have gauges for preheat temp, burner shell exit gas temp, cyclone exit gas temp and cooler exit gas temp. I don’t have a temperature gauge in my hopper. My first run burned down to the restriction! Hmmm? Too late! I know a new load of wood cools the hopper initially, so the temp then rises as the burn progresses and at 400 degrees you refill. Where about in the hopper have you placed your temp gauge? I think this might help answer my refill question (monitor the hopper temp). I was looking for something to indicate feeding time.
Is the stainless steel area insulated? If so, what did you use and how thick.
Thanks for the post, Herb, DOW.
Pepe

Good morning brother Herb.

Sorry to hear about the pop-off :disappointed:

It seems that when building a new charbed or after a charbed has been disturbed the gasifier will use 3-4 times the amount of wood .

I am not sure the low char could have caused the pop but we know you were making gas :grinning:

Should have gotten some high temp reading at the cooling rails and hopper .

Thanks for reply Jim, Pepe and Wayne!
Pepe, down to the restriction, I thought mine was low on fuel!
My temp gage is about half way up hopper, it’s always been pretty dependable, when it gets to bout 400 it’s pretty well out of fuel, I just wasn’t watching it close enough, somewhere between being thrilled that it was running again and figuring I still had plenty fuel I didn’t think about checking gages, that big BANG woke me up real good, seems like the car blew up off the hiway about 2 feet, everything shook, I looked to make sure there wasn’t anyone behind and checked for flying debreh on the road, switched over to gas and went home! It was good gas alright Wayne!
As far as insulation behind the SS Pepe the only place I have insulation is in the bottom barrel, at least i used to have until this last Bang! hehehe
Herb H

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So THAT is the “Big Ban Theory”. You run out of wood. People have been talking about the Big Bang Theory and now we know how the world was formed. Herb’s gasifier in another time.TomC

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glad to hear your on the road again herb . I do get a backfire at the intake If my hopper is low and I think I can make it to where I gots to go.

Thanks, Herb, I was thinking that would be a good start. I’ll install it and burn some more wood and shut down at 400 degrees and see where the fuel level is.
Pepe

Glad you’re going again Herb. Problems are a headache though. A clean out is always an unknown for me. Sometimes it’s like I never toughed it, and other times it’s like demon possessed! I’m sure you’ll get it, because “she” is your creation. Good luck.

Dang if it didn’t do it again, this time I had just lite it, got a nice burntube of red hot char, put in enough fuel to bring it up above nozzles, shut puller fans off and just let it brun up thru the hopper to gain some char and then I was going to put fresh fuel in it and go for a hide! After the flame started coming up thru the hopper real good she let go! BANG! It bent all my spring loaded doors again not to mention scaring the HELL out of me!
I’ve got it backed into my now AC shop and going to go over it with a fine tooth comb! I figure it must be pulling in some air someplace or it wouldn’t have that potent mixture, I probably forgot to put a plug in somewhere or something else stupid, stay turned , still learning! Herb H

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You said you shut off the puller blowers. Then you let it burn. With the puller blowers shut off the smoke ( gases) go up into the hopper. If the lid is down, you are just about guaranteed a sneeze. The gases mix with the air that was let in while the lid was open. When the “right” blend of gas and air is reached and you have the fire, it ignites. Mine will give a sneeze even when I keep my puller blowers running, if I open the lid and don’t fill it clear to the top with wood to take up the air space.TomC

Yeah Tom that’s right, that has also been my experience but I was still in fill mode with the lid wide open when it blow! I’ve never had that happen before!! It has to be pulling in air/oxygen somewhere for it to do that!

Good day Herb,and good luck finding the puff problems.if your inlet air was open,might that draw in extra air while fans are in normal vac.I wounder if the inlet air was shut and reg draw fans were on with lid on shut it would remove the air better, just a thought for testing,turn the radio on .

Hi herb,i dident know if you had heard chris,talking about putting extra sensors for the hopper temps,so a light comes on or a beeper sounds too remind us.Glad your back in the game,and feeling good.

Mr. Herb
I’ve had a very loose char bed and had it go off under the grate shortly after lighting up. Chris had it happen at Argos too.

Had a very successful run this morning, I think your right Marvin between a loose char bed and doing my gaskets a little different that didn’t work out so good I got a good ride this morning! Great to have the Caddy back!

Hey Marvin, I often think about the night you picked me up at the motel in Nashville and took me for a ride in your truck, thanks for doing that!

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For your sake, I hope it was just a loose char bed. Unfortunately, I just put my truck back together after some major work, and took it for a ride. It wasn’t working very well. I had to add wood on the ride and when I did it sneezed back into the bag I had just dumped the wood from. After, it cooled down I gave it a good inspection and “thought” I might have a bad gasket. So I tore it apart again. I’m going to be upset that I didn’t read this post before I jumped on taking things apart.TomC