I don’t know if you ever encountered a pitch pocket in old growth fir but if they were damaged years ago a pitch pocket will form in the area where it was damaged. Sometimes you fall one and literally gallons would pour out like honey.My dad used to sell wood to the railroad for fuel. They would also have drums of this fir pitch at the ready and if they knew a big hill was coming they would dip the 4 ft wood chunks before throwing them in the burner. the edges of the pocket we would split off for kindling,no paper required. Ahh the old days, my dad has long passed on but I used to love his stories. My question is, although it sounds stupid what part is the actual hearth?
David and SU, I think my hearth pics are on another thread, but here’s a couple and a diagram of my internals to put the parts in perspective.
David, I know what you mean. I had so many distractions this year that I never fired up my gasifier until October. aggghh.
Pepe
Thanks again Pepe and steve U and all. I just read your thread about gasification math made easy. Wow. Havent messed with the machine this week but have been drying wood for some tests. The wood was fell last spring and sun dried till about September and then shedded. I am using the back of my hearth of my wood stove for further drying. I am trying uniform 5 to 7 inch rounds cut into 1inch and a quarter slabs first. Then I will go from there hopefully learning something on the way. Got time to drag out the old Kohler motor this morning and get it where I can mess with it. And YES it has an electric start on it thank god. In the last 20 years I have repeatedly threw my back out pulling on pull cords. Don’t bounce back as fast as I used to lol. Will have time this weekend to play a little more.David L
I guess this Is the right place to put this. Wondering if someone might recommend which system would be good place to start for running 18 - 24hp twin cylinder like Onan or Kohler gasoline fired unit, I have one of theses on a portable welder that I am thinking of moving to remote property for building a cabin and maybe even leaving it there for 9kw power supply
Hey Thomas, what speed does your engine run at?
Arvid, Thanks for the response. This unit I have runs at 3600rpm. It is a lincoln portable welder / generator. Being new at this and still reading until my eye’s burn every night, I am wondering if I might have issues controlling the timing on this engine also. It is governor controlled but loads can be heavy at times if using as a welder.
What are your expectations of this welder being gasified… you won’t get anywhere near full power out of it… expect maybe five Kw on wood gas. will that be enough for you?
I believe that would be sufficient.
Here you go Steve U. I made a 10 second video for your post for easier downloading.
I did get it running before but didn’t have it fine tuned with the air mixture. I had a 3/4" valve for the air but changed it out to 1" valve. It runs pretty good but I think there’s more in it. I have a 2" restriction in it now, maybe I could try a 3" restriction? It seem s to run good when driving on a gravel road with the bumps, I believe this is telling me I need a shaker. I acquired a starter from my Ford and the bendex is out.
I was using 1 1/2" Pine blocks that I cut up from 2x4’s we tore out of our office. I think my fuel should be reduced even more because it seems to get hung up above my funnel. I received some 3/4" Oak strips that I may cut to 3/4" long and see how that works.
Steve, I appreciate all your guidance so far. I’ve been working for 7 months to get to this day. I’ve read and reread your posts to gain as much understanding as I could about gasifiers. It has all helped and now I have the opportunity to gain the other 75%.
One thing I did learn from Terry L was to run the blower side of a wet/dry vac into the air inlet to push the air to the tractor. It gets the grate temps high real fast and the tractor is a lot easier to start.
I still want to get vacuum gauges installed and hook up my other thermocouples. The one thermocouple I do have working is at the gas out flange just outside of the main unit. I’m receiving temps right at 300 C. My first run was at 460 C. Then I fixed the air leaks.
Thanks for everything so far
Steve,
Thanks for reply and input.
I do believe some of my luck had to do with using wood chips as fuel. It did produce other problems but gave me the drive to want more. I will reassemble that unit with some revisions. I think it may be useful for a small condensed unit. My curiosity of how long it will last is getting the best of me being made with 14ga steel and the air cooling the firetube from the top where the temperatures are the greatest.
I do have raw fuel but unfortunately it is cut up to fit a wood stove. I have an idea to process it to smaller pieces but this will require more time.
Hey Y’all,
Just wanted to share my first entry into woodgas. Old lawn tractor with 14.5 hp briggs. Runs great but haven’t had a way to load it yet.
Try tall grass, dull blade, up hill. Ha.
Need a little input
I got the lawn mower up and running with the gasifier. I was able to run about a 1/4 mile down the street and the lawn mower just quit running. The grate and exit gas temp were higher than prior to that point. I poked the wood to see if that was it, to no avail. As I was trying to start the engine, it kept backfiring. I actually had flames shooting out the air intake with the backfires. Fortunately I am now able to use gasoline to get home with the new wood gas line to the carb.
Does anyone have an idea of what I ran into here? By the time I got home it was dark so it was hard to assess anything.
Well BillS I’d say you “lost” reduction char bed faster than it could replenish itself.
You then biased from a temperature reducing CO2 to CO “reduction” to a heat making combustion mode.
Your output heat increase. CO2 combustion gas will not engine fuel. You getting combustion/back fire flames.
Unusually this is caused by hopper fuel bridging then creating a material gap; starving char replenishing and allow oxygen then down through the grate - into a lower combustion mode.
Can Also be caused by a grate collapse failure too.
You will need to dump out and inspect.
S.U.
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Hey Bill,
You might want to look down your intake manifold also.
Enough soot will cause the valve to not seat completely causing the ignition to follow back up to where your air mixture is.
T
Thanks Steve and Terry G. I will check those tips out. Terry L also gave some input for me to address. Everyone’s insight is much appreciated.
Thanks steve for the kind words.
Now if we make our own pellets…
We could just as well build that machine couldn’t we.
That would be the obvious choice but sadly this old mower is completely froze up and non functioning. Didn’t want to tar up my good one Ya know.
Hi all,
I think I read somewhere in this small engine forum about the pulsing from single cylinder engines. I have observed on mine that a regular puff puff of gas comes back out the air inlet when running. It runs fine but seems like wasting a lot of my good fuel. I was pondering if something as simple as a check valve would effectively stop this. Any thoughts?
Andrew, if the intake valve is seating properly and the valve timing is right it seems to me that it should not puff back into the system - just interrupt the suction cycles unless your setup is making gas faster than you are using it and it builds pressure?