yep, the link is on this site. Those large V8’s move gas really fast when accelerating. The gas and air need time and space to mix.
Hi BrentW.
Reasonable thinking there.
I have a 94 SEFI 302 Ford with also a dual snorkel inlet throttle body. But mine goes into a long log mixing section that feeds equal length rams horn individual cylinder runners. So seemed reasonable that air in one side, and woodgas in the other of the common shafted throttles would yeild a 1 to 1 ratio. Did not work. Heres why.
The air is being pulled against virtually NO restriction.
The woodgas side ALWAYS has restriction from the oxidization zone and reduction zone fuel particle beds then the added restiction of all of the external de-ashing and soot separation, cooling and final filtering and piping. So . . . .always wants to pull in more air then fuel gas leaning out the mix ratios.
Also you do want to be able to vary the mix ratio somewhat for different conditions.
You do need separate engine air sucked in from engine sucked in fuel controls. These can be variably manually and/or activly linked and controlled.
Regards
Steve Unruh
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Hi Steve,
I had posted before on the topic of using compressed air to “force feed” the gasifier (not a good idea). After reading your post above and the 0-60 MPH HP measurement thread, I thought would ask again about using a fan or blower to help offset the restriction losses in the gasifier and return a more balanced air flow. Difficult to do, perhaps, but it may be possible to make the gasifier flow better and produce quicker from off idle or low RPMs by offsetting restriction losses using the proper amount of forced air into the gasifier.
Dave,
Go BIG GREEN MACHINE !!!
Hey NY GaryG
I only have very limited experience doing this on a single cylinder 305 cc B&S engine. Works. But then changes your whole dynamic set up for air/fuel at idle control. If set up to normally fuel gas suck then wants to fuel gas floodout with the pushed gas displacing out the air at cranking to start so then needs a variable gas side flow control valve too. Set up for this you would then be dependent on your fuelgas “pusher” system being absolutely dependable for quite a bit of running time for at least all idle and off idle usage. Most blower systems available/used do not have that high of a duty life cycle.
Subjectively on the B&S it did give better off idle power push deolvering the fuel gas. No change in the max RPM measured engine power - if anything the blower then flow inline seemed to limit max gas flow. Another factor to then have to work around.
Could be made to work with lots of development and a certain amount of additional complexity.
Regards
Steve Unruh
I live in Alaska, How does the extreme cold effect wood burners, I am thinking of the condensation freezing causing problems, any info there?
Thank's BJHI ROBERT, A GASIFIER BUILT TO RUN IN ALASKA, NEEDS SOME SPECIAL INSULATING AND I AM NOT THE AUTHORITY ON IT. BUT MY BEST ADVICE IS TALK TO MIKE LAROSA, HE HAS RUN WOODGAS THRU SEVERAL WINTERS, I LIVE IN OHIO AND THE WINTERS HERE ARE COLD BUT NOT TO BE COMPARED TO ALASKA. I THINK DRIVING ON WOODGAS IN ALASKA IS VERY POSSIBLE BUT SPECIAL INSULATION AND INSTALLING A HEATER IN THE CONDENSATION COLLECTION TANKS WOULD BE NESSESARY. MAYBE MORE ? DAVID-O
yes i had forgot to mention i would have valves so the fresh air would be adjusted and restricted, and able to turn all the way open for gasoline use, but i see now this is just as easy to mix in the air box before sending to the 460
Thank’s Dave new here, awesome stuff. Hope to build something this winter in my shop.
Hi Dave,
What did you design for a clean out on your gasser?
Peter
GOOD MORNING PETER, MY GASIFIER WILL SET TOO LOW FOR A AMMO BOX TYPE BOTTOM CLEAN OUT . SO I DID IT LIKE MY PREVIOUS GASIFIER AND WELDED IN A 4 INCH NIPPLE CLOSE TO THE BOTTOM , THAT HAS A CAP ON IT, IT WORKED VERY WELL ON MY OTHER GASIFIER, I CAN REMOVE THE CAP AND JUST CLEAN IT OUT BY HAND, I MAY ADD A 3 OR 4 INCH CLEAN OUT PORT ON THE BOTTOM OF THE GASIFIER ?? SO I CAN WORK THE CHAR AND ASH INTO IT SO IT WILL TOO FALL THRU THE HOLE, I THINK WOODY HAS A SIDE CLEAN OUT ALSO ??
Arvid Olson lives way up north in Ontario and he runs his unit all winter long.
Thanks Dave,
That seems to be fool proof. Maybe bottom mount 2 of these? Is the cap just hand tight?
Peter
HI PETER. I, SCREW THEM ON SNUG, NOT REAL TIGHT. LOOK AT THE PHOTO,S I WELD A LARGE NUT 1 1/4 INCH ON THE CAP SO I DO NOT NEED TO USE A PIPE WRENCH. JUST A RATCHET WRENCH. HAND TIGHT MIGHT LOOSEN UP ? DAVID-O
Hey Dave,
Those screw on caps get stuck with rust after a while. Maybe graphite and grease on the threads will work to keep them loose. I have a door on my clean out that is bolted on and no hinge. Works great with a large slide in pan, like a baking pan or cookie sheet for ash removal. The door is sealed with red silicone high temp caulk and has been opened and closed many times in the past year without leaking. Regular silicone does not work as it breaks down from heat.
The big thing with screw on lids are tiny air leaks through the threads. Teflon tape won’t hold up. You have to make sure the thing is sealed air tight after heat has affected it.
A small scoop or hoe will work for your ash removal. Long handle for getting all the way in there. Leave some ash on the floor to insulate from the down blast. I never completely empty my gasifier.
White edges on char indicate air is getting in. White ash trails on the walls of the ash bin indicate air leak origins.
Shop vacs plug up fast and spew black dust everywhere.
Have fun.
The videos I’ve seen of WWII units still in operation they do grease the threads on the cleanouts, for exactly this reason. Also a good idea to grease the seals on your lids to keep them from sticking.
HI GASSERS, WE ARE PAINTING AND UNDERCOATING THE FLAT BED AND I WANT TO START MOUNTING THE GASIFIER ON THE TRUCK THIS WEEK END, I WILL START POSTING PHOTO,S BY TUESDAY I HOPE. I HAVE BEEN WATCHING WAYNES VIDEO.S . THEY ARE GREAT, THEY HELP ME PLAN OUT MY NEXT STEPS. I WATCHED THE ONE ABOUT THE STRAW FILTER AND I HAVE ALREADY BUILT IT EXCEPT FOR THE BUCKET WITH HOLES IN THE BOTTOM. , I WILL NEED TO BUY NOTHING BUT THE STRAW OR HAY. SINCE I DO NOT LIVE ON A FARM. BUT I DO HAVE A GOOD FRIEND THAT IS A FARMER AND HE WILL SELL ME A BALE. I HAVE PLASTIC BUCKETS, AND COULD USE ONE IN THE BOTTOM OF THE HAY FILTER, BUT IN MY SCRAP I ALREADY HAVE A PIECE OF STAINLESS WITH 3/4 INCH HOLES IN IT. I FOUND IT AT THE SCRAP YARD SEVERAL MONTHS AGO. PHOTO POSTED HERE.
THANKS WOODY, FOR THE TIPS, I WILL USE YOUR ADVICE TO IMPROVE MY GASIFIER.
HI CHRIS. THANKS FOR THE GOOD ADVICE, I WILL USE SOME GREASE ON THE THREADS AND LID SEALS.
Nice Grate!
HI CHRIS SEYMOUR. A STRAW GRATE IT IS. I DID NOT KNOW WHAT TO CALL IT.