Drive On Wood!

Gee Chris Saenz I am flattered and a-l-m-o-s-t speechless you would do this.
Thanks for keeping this out front in the general read section. Could you please work "Small Engine" into the title too please.

DavidB. yes I think Waynes "Keith System" can be down sized to gasoline/propane rated +/- 20 horsepower spark ignition engine ranges. Same system size probably able to go up to an actual 40 horsepower on woodgas capable putting it into 3 and 4 cyclinder 1800 ROM engine range. Call this a Small system. Smaller than this is really a Micro as in Dutch John's; rhe smallest choke plate Victory Hottwatt; the smallest restriction GEK configurations. Fuels sizing becomes a PITA with the really small 3-12 hp engines. As I recall the rated CFM on a ~5hp gasoline engine is only ~15-32 cubic feet flow per minute Not much draw foe any gasifier. Just look at the tiny carb and exhaust holes, and tiny small valves when you go this small. The three builders I quoted recommend and/or do use more and more internal/external insulations and then SS or ceramic guts to withstand this then held inside heat. Waynes as carbon steel needs to shed out some core heat.

Pet project of mine has been to take a standard rural/urban riding lawn mower, 100 amp car/PU alternator and see with the mower deck pulleys and parts just how effective of a "Nail/Stone Soup" woodgas home charging system I could cob up.
Rule of thumb using automative type DC alternators at only 40-60% efficiency is you need ~1 shaft horsepower for every 12vdc 20 amps charging. Yes, really, only ~280 usable electric watts. So yeah need to start with at least a 15 hp rated gasoline engine with woodgas AND Engine Speed Derating. Derating engine speed helps much with the scream-a-matic air cooled sound, engine life and woodgas fueled needed ignition timing advance change.
Ha! Ha! I will be able verify and qualify a Keith System able to do this by summers end. I want greenhouse heat and Lights this upcoming winter. Woodstove heating only gives me the one not the other.
Yeah, yeah MicroCoGen fellows I know be better system efficiency to go with 24 - 32 - even 48 VDC system. But since the inefficiency IS waste heat from the alt unit, pulley drive and light bulbs then as a greenhouse heater/illuminator it is all good. Sic: 1000 watts electrical out = 1000 watts heat out off an auto charging units. Why you have to spin the DC alt head at least 4000 RPM so it will self fan cool itself. Engine fan and alt fan are your air circulating sources. Use these DRY heats along with rising engine DRY exhaust heats to pre-dry my always +20% fuel wood and this moisture then humidify the greenhouse.

Hey Gary "I think" woodgased this engine would have enough power to operate a small Kieth/A.Juso style shear chunker. I do not "think" it will do it through through a belt driven Hydro trans-differential. Not geared low enough. Hydro trans "may" just just fluid coupling stall out (slip) or the unit drive belt(s) slip on this kind of load. Only way to know is to try it. Study Wayne's and the Finn A. Juso's (sp) videos. Build the chunker shear head and try it on full power gasoline engine power first.
If this is a Briggs, Tecumseh, or Kohler with the ignition points under the flywheel for some of these there are electronic ignition conversion kits available. Try an Internet search for this. On disassembly look also just how you could ~15 degree advance the timing from stock.

Regards
Steve Unruh

Sure. Sure. GaryG. These little Nissan DOHC I-4's when running well tick over nice and smooth like fine watch.
"Small" for a woodgasifier fueled engine is really defined by the low continuous low horsepower needs. Read DJ's Microgasifiers PDF and you will see he was fooled designing for his "Tiny" (DJ3) lawnmower application when the gas flow wants were NOT following the engine horsepower rating but the actual est. 1 horsepower his rare English power reel bladed mower needed. Less horsepower to fuel -> less woodgas needed -> less woodgas needed -> less heat generated -> less heat generated -> less heat available to drive the fuel drying/pyrolisis/oxidization/reduction conversions. Smaller the gasifier system the prortionally smaller the weight and fuel "bit" (chunk) size causing gravity fuel flowing down problems. Smaller the gasifier size as he said the smaller the hot internal space volumn mass to the outer radiating surface area. Example: same cool climate; BIG cow - short fur. Smaller the animal, the thicker the fir needed to cope with the cold. So every factor on small gasifier systems is driving you into a Humpty Dumpty, Ring Around the Rosie, we all fall down system collapse into a cool tar soot mess.

GaryG this direct cam over the valve engine is defiantly a valve will hit the piston engine with any problem. It will not just bend the valve stems, but with no where to bend aside safely will break the valve heads off imbedding them into the piston crown and often even scoring the cylinder walls in. So be sure you work through ALL of your system/operator possible tar issues on your Gosellin/Dobson/Keith hybrid design on your nice safe garden tractor engine first.
BTW second mowing of the year I went out and really stall loaded that rider of mine with the hydro trans in my pictures. Yep the single small upper pictured trans drive belt would just spring arm tensioner scream and then the belt slip. PITA to change this belt on mine.

Welcome DaveB.
THE most important woodgasifier lesson is to go somewhere and see, hear, feel and even taste one successfully fueling an IC engine under loaded power. You betcha'. Go there and get it really in your blood. You will figure out the tasting part from opening up and peeking into hoppers and whiffing the erie weird yellow hopper smoke. If you just must finger dip some hopper condensate ONLY just tiny bit to the tongue man. Takes days for that to go away. Hey! Don't all curious inquisitive little kids do that? Thats woodgassing. Makes you feel young again when the world was simple and directy understood.
Maybe woodgasing IS the fountain of youth, eh?!

Regards
SteveU.

Hi WilliamS
My avatar picture is actually of the valley I live in. Hills and trees to the right hand usually take the hits. Yep most always make a couple of trees zippered bark and cooked. Then fire wood for sure before the bugs get them. Sending through a picture from my front porch showing the rock out cropping and 110 year ago wildfire burnt old growth stumps now exposed from a current logging operation. This time it was the different tele-communications antennas and dishes on the top of the mountain behind me from this picture taken vantage point.

I've been doing some current Kohler and Briggs and Stratton reading on my menagerie.
I was wrong. None have built into the factory magneto coils electronic spark advance. Some models do have available an cutsie named added on electronic timing control module. ALL of the single cylinders above ~?? hp have some type of cranking speed internal automatic exhaust valve compression release. You are then not able to do a meaningful compression tests. Don't get caught! Do catch a give-a-way unit with "bad compression". Ha-haw! Now I know why a particular 8.5 hp Briggs gen-set is sometimes a devil to crank over. And most of the late 90's and 2000's single cylinder ~10 hp and above do have some type of inside the crankcase active counter/anti-viberation balancing system. Some OK. Some scatter'em lower ends. Thanks to the Internet chat groups I passed on a four year old $200. Craftsman with a 20 hp no run engine "just needs a carburetor". Naw, bad/worn cam system from metal contamination wear particles out of the weird oscillating crankshaft mounted balancer system. And instead picked up a 10 year old Scotts with a four ways bad mower deck but a rock solid 17.5 hp, tight steering and good Hydrostatic transmission just like mine.
Sure pays to read. Glad I got Internet back up the day before this estate sale.

Regards
Steve Unruh

Hi ErnstG
No problem is/was not with the pressure waves back into the gasifer/producer. In the hearth charcoal area pulsation is actually beneficial for clearing the char of surface ash.
System pulsation does screw a bit with effective cyclone separation. This is easily worked around with a settling chamber separation system instead.

Yeah. I thought it would be easy on a single cylinder four stoke to tune in some intake manifold induction length ram charging. Worked OK on the air side. Terrible on the gaseous fuel side when sucking through the restrictive char/fuel bed of the gasifier. Reverse pressure waves would stack back pulsation's of fuel gas to the gasifier bed restriction point and the reflected pressure waves of fuel would never co-ordinate with the delivered air pressure waves for good consistent air/fuel ratios..
I did work on this all of the winter of 2010-11 with different tuning lengths and air and fuelgas side pulse dampening reverse flow edges and restrictive balancing air filters.
Bottom line was unit had always worked just fine through the original restrictive gasoline carburetor venturi restriction with stupid simple mixing in the original air cleaner housing. Just choked back to 1500-2000 watts out of a potential 5500 watt electric output rated unit.
Eliminate the venturi restriction with wide open like fuel injection tubing and I could manually tune and hold 3200 watts load continuous. All of this was without engine compression, valve or ignition timing modifications and at a demanded 3600 RPM +/- a 150 RPM for 60 hertz fequency control to be able to operate consumer electronic devices.
Problem was with electrical load changes all of my affordable KISS mechanical pressure balance actuators for multiple cylinder control ideas would NOT work without a steady intake vacuum. Sure, sure. Could have been high speed electronically controlled. But $2-300. of electronics (retail) on a $600-800. Sears/COSTCO/Harbor Freight gen-set in addition to the same (retail) in intake manifolding, valves and actuators did not make sense.

For the same few hundred in electronics for off the shelf DC to AC inverter(s), then simply engine over-sizing, and now spinning "I do not care about RPM" high output DC automotive alternators put "Replace with known good part" user KISS back into the system package.

Active woodgas fuel producing makes things not straight forward as compared to gasoline, LPG and CNG techniques on small engines.

Regards
Steve Unruh

Good reply TomM.
I come up with a similar answer based, as yours, on real working systems. Don't freak at my much higher base rated engine horsepower needed based on real obseved wood gas converted engines. A min 30% to as high as 50% penalty in loss of engine shaft power:
17.5 kWe/28 hp Generac V-Twin system; 6500 int/5500 continuous kWel/9 hp Briggs system; 1st generation Victory 5000 watt (el) sets.

ArvidO for a full 5000 watts electrical continuous able to use you would need SIX of those 75 amp nominal 12vdc auto alternators as shown on the "Czech 3.5 hp system" thread here being driven by a gasoline rated ~18 horsepower engine once it was being then woodgas fueled.
Helped a friend evolve to this for 5000 watt electrical woodgas fueled systems. He used TWO specially made 200 amp X 12.5 volt late model Ford internal fan pattern alternators for his nominal 5000 watts system output. He uses a three cylinder Methane rated ~18 horsepower engine. I pointed out an approximate 5-10% conversion loss in the DC to AC inverter and cabling to flow this high of amperage. Engine had its own 40 amp X 12.5 vdc charging alternator so another 500 watts there could be counted as generated too.
I am now staying at home now for the last year and he has moved on to I think 32? or 48? vdc alternators for their ~20 and 30% higher conversion efficiency and to get the amps down to make cabling more reasonable. Amps should now be down to only ~136 and ~96 respectively. Ha! Ha! Higher rarer, Special alternator and inverter costs now though. The Less amps, the less heating and longer potential service life.
Standard 12 vdc alternator are no higher than ~50% shaft to electrical output conversion efficient.
Means at a 5000 watt system electrical load most common auto alternators WILL be kicking out and needing to shed 5000 watts of waste heat. 'Nother ~500 watts of waste heat coming off the inverter at this load (why they are so heavily finned and in larger sizes have their own cooling fans).

Past multiples of ~500-875 Watts made in any way and for the higher conversion efficiencies it gets really dollar expensive.
If you want to study up on all of this in plain English read here:
www.microcogen.info
Especially the Automotive alternators; Project systems; Propane, Methane and Producer Gas Engine, and Fuels boards. Good written articles now in the White Papers section too.
Me, DavidB, Gary Graham and a few others here are active members there learning from others actually living it and doing self/home power generating all over the world in many forms.

I always say now with woodgas fueling NO heats are a waste if it can be use them to effectively dry, and pre-heat condition fuel wood to an ideal reactor hearth delivered 10% moisture or less. Using this philosophy allows using cheaper more available engines and charging components simply oversized and ganging them up and harvest the waste heats for fuel conditioning wet picked up woods in my 9-10 month a year rainforest climate. Out fir trees do grow here year round converting solar to usable fuel even in the clouds and rain.

Regards
Steve Unruh

Hi BrianH.
On different DIY home power forums I've heard this talked about a bunch. They look at the water cooling as an easy way to get pumped heat for CHP (combined heat and power systems). Also the water jacket and ability to as you said down the RPM would really lower the noise. But so far I've just heard talk with no actual documented doing.
The reason is costS. Even an outboard with a freeze damaged lower case has such a high salvage\/parts value you could sell it and go out and buy a new dedicated industrial engine. AND then parts cost maintain it for less than 1/2 the costs of marine. This summer I bought a whole ~500 hour 18 hp Kohler engine for just $300. with a riding lawn mower with useable parts wrapped around it. Can't touch anything 4-stroke marine around here for less than 5 to 10X of that.
Do you have an unused 4-strke outboard available?
Ha! Ha! My wife has this 15 foot fiberglass 1964 family heirloom boat she chides me to get back running. 4-stroke lake requirements too many place here now.

Regards
Steve Unruh

Hi All
Bruce French "woody" now has his woodgas converted Dual Overhead Cam Ford Ranger engine down and out now for the pistons bending the valves:
http://driveonwood.com/forum/631
Some nice busted parts engine pictures there.
He says on trear down this was NOT (this time) a woodgas/tar problem but a reoccurnace of a timing chaim problem he first spoke of here:
http://driveonwood.com/forum/204
Seen too many of these failuers in my Auto carreer. Always expensive. Why I say just don't use any DOHC engine for woodgasing.

Regards
Steve Unruh

Hey BruceF
I did not mean to highlight, put you on the spot. Just wanted the Wonderer Why'ers to see the good valve/piston pictures Sean posted up.
I have that street racer DOHC Mitsubishi Turbo Coupe that snapped the balancer shaft drive belt, sewing machinelike feeding the broken end up under the T-belt causing it to jump timing on both cams breaking off the heads of every single valve burned into my memory and pocket book. I think I told you directly about that one didn't I?
Regards from a friend who's been there.
Steve Unruh

HI Folks time to update this topic a little.
Hippy, skippy down and look at the posted up picture first for reference. Loaded full page resolution if you can get it to expand out to full page.
This is almost my "Whole Motley Crew" of yard and garden four-strokes engines.

All of these could; have; and been: woodgasified powered by me or someone else I trust in the last few years.
What have been the results? Well . . . just OK, Good, Very Good, to Not-So-Good, to very, very Bad.
The Bad first. The little Honda tiller left hand midground. ONLY a 49cc engine overhead cam engine. A real lightweight gasoline fuel sipping engine. As poor Brain Hughs will tell you now tiny engines will not suck a gasifer hard enough to make good fuel gas. This tiller is aluminum cylinder bore worn-out dead now. Honda put the tiny air filter down in the raised up dust behind a soft plastic "easy service, tool-less" snap-on cover. One unseen bump in the 3rd year on a wooden garden stake broke off one of the plastic snap fingers allowing dusty gritty air pull in and by the time I was done between the rows tilling in dusty August this engine Hot was running more on sucked up crankcase oil than gasoline. I had to stall load it out to kill it to get it to stop. It then didn't need an ignition spark or even gasoline then, igniting on hot glowing oil carbon deposites and heat vaporized engine oil. Removing the remaining engine oil once cooled, it was like liquid silver from the abraded away aluninum piston and cylinder wall. I saw this too on a bent shaft Techumseh engine I intentionally ran to destruction on un-ash filtered charcoal gas to see how quick/how long.

The Not-So-Good. Right hand black mower with the Honda 149cc 5.5 Hp engine on it. (My wife's personal house yard push mower) Again too small of an engine to suck a gasifier hot enough. WHY even risk a chain driven overhead cam disassemble tarring clean up problem when there this all of those easy disassemble 5, 5.25, 6.5 and 7.5 hp engines surounding it?? Note the blue plastic tape now holding the "Easy Service" now broken off Honda plastic snap on air claner cover from under yard bush and picnic table oops rubs and bumps.

The just OK engines. Left to right in the front row a 5 hp, and far right a 5.25 "flat head" "valve in block" "easy to work on! Oh really? Ever done a vlave grind and clearance set?!!) Briggs and Stratton engines. The two tipped up mower decks behind had flat head Tehcumseh engines on them "sacrificed" to my early charcoal days fuelgas experiementing.
While I haven't been doing any personal woodgas fueled engine running this winter I have been winter visting set-up locals who have been woodgas fueling these styles of engines weekly. 50%. That's about the best power you will ever get woodgasing/charcoal gassing these flathead engines. Low compression ratios. Difficult ignition timing improvement possibilities. Very restrictive in and out of the same side of the cylinder gasses flow capabilty with the in-the block valves and the torturous gasses flow pathways. Still . . . those using these are pretty much happy with Free to $20. USD used engines. The same in a car or light truck alternator getting 800 to 1000 watts with picked up woodfuel in just about any lashed up of a wood fueled gasifier. No charcoal gasing done here PNW wet-side due to wet wood fuels, and not want to smoke signal to others. Ah . . . folks doing this pertty much what to live in seclusion out in the woods and not be noticable. Engine/alternator system are wooden beam/plank base mounted. Unbolt, tip off the ran out units, redrill and re-mount for different "volunteer" units. Wooden base gets to "holey", then cut it up as gasifer fuel and chainsaw out a new one. 'Gitter done works just fine for many. Everything does not have to be such a big over-thought-out manic deal. Not folk you will ever hear posting up about thier systems. Most Internet at the Library for anonymity.

The Good engines to woodgas fuel:
Front row the black overhead valved 6.5 hp B&S in the yellow and green high wheeled self-puller (my personalcurrent grass mower - wife bought it for $30 as a gift to 'ol me).
Mid-center the 7.5 hp over head valve horizontal shaft B&S in the garden tiller. Bought new.
Left hand corner in the 3rd shop bay is the 10.5 hp overhead valved B&S on the log splitter. Bought new.
Back center you can just make out the aluminum overhead valve cover on one of two idenical 17.5 hp overhead valved Kohler engines in one of the two older now rider lawn mowers. Both bought new, now with 1500 hours each plus.
These overhead valve engine are genrally larger in cc displacement for thier base horsepower rating have higher compressions ratios needing No, or less ignition timing improvements, and have very open generous intake and exhaust flow paths with thier now "cross flow" cylinder heads.
Expect at least 60% power equivalencies on an unmodified engine. Good fuel gasses mix composite woodgas blend I and other now have hundreds of hours of loaded running at 70% power equivalencies now with NO internal engine modifications. DO have to get rid of the orignal gasoline carbuator venturi flow restictions to do this. Do some additional compression ratio bumping up and give a bit ignition timng advance improvement and 80% power equivalency would be possible.
I'd personally save to 90% power equivalency goals for water cooled engines. Even good composite woodgas fuel just not as heat efficently shaft power converted as spec gasoline/propane/diesel in piston IC engines. That heat/pressure not shaft power converted to mechanical comes out as hotter oil and hotter cylinder walls and cyclinder heads needing heat rejected cooling off. Waterccoling better for this.

None of this is blue sky speculation. These Are, or have been my working grass mowing loaded machines.
Ha! Ha! Good example of real in the world efficienies closed cycle efficiencies here.
Same one liter of gasoline in the Honda push goes for ~about two hours mowing time. One liter in the B&S overhead valve self-puller mower about 1 1/2 hour mowing time. The earlier flat headed engined push decks in the back, the front row flat headed push, and the front row flat headed two wheeled string mower in the front are only good for one hour of loaded mowing time. Which is most efficient?
The self powered puller OHV B&S. I can do 50% more area on one craft, operator coolant, carbohydrate beer than on the others. And they all end up being two beer machines a full fuel tank to operate. The rider mower is the worst by far! 1 1/2 US gallons (5.68 liters) a loaded operating hour and a sore, sore back and I cannot walk without apelike knuckle dragging for hours then. Does save on the craft beers electrolight replace ment fluid cost though. Push/walk-behind mowing I cramp up badly later on just straight water coolant.

Regards
Steve Unruh