I have used a router speed control (SCR circuit, I bet) (light dimmer basically) with some luck with AC universal motors and a little less luck with small blower motors.
I like the anvil! Usually the horn is all beat up and by the taper it must be an older forged anvil as opposed to a modern cast steel one. Does it have a good ring? Have you built a gasifier yet? Just curious why you are working on the blower first. The air mattress blower you got at Goodwill is fine. Forget about the 130 watt fan as it is too big. It does not take much air to start up a charcoal gasifier. If you haven’t started your chargasifier yet I can give you a few simple step by step instructions that will have you making chargas quickly with little expenditure.
Gary in PA
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Hey Gary, I built the blower mostly just because i had that gearbox laying around and i wanted to do something fun with it. I have not gotten any actual building done as of yet, and the powers that be have delayed the open burning season here and so i have not wanted to try and make any charcoal yet this year. I have been making char with a retort to use in the bbq, but I need to work on a good way to grind and sort it. I will post some pictures once I get something done.
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Well I have finally managed to get a little bit of progress on my project, in a somewhat round-a-bout way. I got a free lawnmower engine from my brother who has a fleet of lawnmowers that he fixes up and sells. It needed a new recoil start assembly, had no carb, and had a bolt cracked off in one of the mounting holes - but the price was right. I cleaned it up, and built a plate to bolt on a tube where the carb would go - and brazed on some threaded 3/4 iron pipe to that. It now has a T, with a gate valve on one side that leads to an air filter, and a ball valve on the other to go to my gasifier. I forgot to bring a camera, but I will snap a picture tomorrow and upload of the current setup. I sprayed ether in the ball valve, closed it- left the air valve open and got it to fire right up, so the engine seems like it should be good to go.
I am curious however on 3 points: First this engine has a breather tube, which would normally connect to the back side of the air filter housing. I did a little reading about what they do, and I still dont quite get it. It sucks air into the engine during the exhaust stroke or something? Should I connect it with a short section of hose to my filtered air inlet?
Secondly, there is an engine governor. I am guessing from what I have seen so far that I can just disregard this, right? The control of the engine when running on woodgas will be limited to what I can accomplish by adjusting the air and wood-gas valves?
Lastly, the lawnmower has a flywheel brake, that also shorts the spark plug to shut down the engine. I am curious what the shut-down procedure is for a woodgas engine, and if I can dispense with this piece entirely. It would seem to me that starving the engine of fuel is going to shut it down pretty fast. Is there any reason not to just shut off the fuel valve when i want to kill the engine?
Anyway, thanks as always for any input!
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It sounds like you have a good start. The breather tube is just to suck blowby gasses from the crankcase, instead of venting them to the air. You can just ignore it. For experimental purposes, you can get along without the governor. Later, you may want to make a butterfly valve to replace the ball valve and connect the governor to it it you want to do real work with the engine. It shouldn’t hurt anything to just starve the engine when you want to shut it off.
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Thanks for the input Andy, I have given some thought to trying to make a butterfly valve, but was not sure how challenging it would be to fabricate. Is it fairly straight-forward? The plan is to make the engine run an alternator to charge my batteries, so i assume it will be a pretty constant load on the engine - but do you think a governor would still be good to have? I think I might get a little section of 3/8 hose and a barb fitting to drill into the PVC just downstream from the air filter so that the breather tube is not sucking any dust or dirt or bugs into the crankcase.
Here is a picture of the engine. Its a B&S 190cc. I bought a pre-cut mounting plate that has universal grooves for both the engine and a 10SI type alternator. I need to fabricate a tubular frame to keep it from resting on the shaft.
My plan is to make a compact little generator, and an approximately equally sized gasifier to sit next to it. With only a single 1" hose to connect the two, it should make it really easy to keep it in storage and set it up quickly when i need it. I am revisiting the simple fire thread, then I will probably be back with some more questions.
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Looks good! If you plan to use exhaust to control the reaction temperature, you will have another hose (metal flex) heading back to the gasifier and another gate valve. Interesting mounting plate. Does it come with suggestions for engine pulley size to create optimum engine power at required alternator RPM?
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I found it at here: Vertical Shaft Belt Drive Generator Mounting Bracket Its sort of an eclectic website, but they have some cool stuff. It comes with no info about target RPMs. I suppose it depends a little bit on the specs of the alternator. I am going to start with a 1:1 ratio, and I am planning on maybe putting a tach on my engine, and an amp meter on my alternator. Once I see what I get, i can maybe try and change up the the gearing to squeeze a little more performance out of it.
Speaking of exhaust, have people found it to be an integral part of running on charcoal? Will the temps simply get too hot without it? I would be curious to hear what people who are running small engines have done successfully.
Making a butterfly that small might be a bit of a challenge, but can be done. Now if it was me, I would install that ball valve directly to the engine and the end where it presently is would be wide open to the wood gas hose. As you have it, you will need to adjust both valves together to change engine speed. It seems most youtube small engine players do it that way, but it’s not ideal. The way I have described, once you adjust the ratio of gas to air with the gate valve, it will stay the same. The ball valve will then serve as your throttle and only it will move to adjust speed.
Edit: the rest of your question. The breather hose would have a slight pressure if anything, so dust wouldn’t be an issue. Bugs on the other hand could plug it up. Running a generator you will definitely want the governor.
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Interesting to see you are advancing with this OrCarl.
Keep an eye out for a free/yard sale cheap overhead vlave version of this B&S engine. You will pick up a bit’o power with less fuel-in useage. These have a stamped steel rocker arm cove on the end of the cylinder head. IF you were raw-wood gasifing these overhead valve types are easier to oopsi!, de-tar, de-stick clean up
Same plate mounting pattern.
Lawn mower engines use the attached blade mass as a flywheel to carry through the four strokes smoothly. Same engine on say a rotor-tiller/snow-blower will have a heavy-mass flywheel to do the same. Yours will be engine smoothed out with the alternator/pulley masses. Expect hand hurting cranking over jarring until you add this smoothing carry trough rotating mass.
Normal horizontally mounted auto alternators can be ran vertically.
The double ended ball bearing units will live longer turned sideways.
All mid-80’s Chrysler/Dodge/Plymouth/Jeep’s use a NipponDenso dual internal fan, double ball bearing alternator. External regulator units; so you can then add your own battery bank optimal three-stage marine/off-grid Better regulator. This is were to spend the money to maximize life on those batteries.
You will probably find running the engine at 2600-3000 rpm to be the best for power, and controllable.
Actual want to spin an auto alternator at ~4000rpm, or more (up to 8000 rpm) for best cooling and loads change power. Look at old riding lawn mower decks for larger diameter pulley for the engine shaft.
Carry-on to generating man
tree-farmer Steve unruh
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I’m not positive about how the 10SI alternator works, but it’s a “single wire” design, isn’t it? (I have one on my old Ford 4000 backhoe). If so, the field current and the battery’s voltage will determine the charge rate. I say this to point out that load on the engine will NOT be constant. As the battery charges, I think its voltage will rise and the current will drop.
Regarding the 1:1 alternator speed ratio:
I think I read someplace that car alternator sorta max out at about 10,000 ALTERNATOR rpms.
And that they usually drive the alternator at about 3 times the engine speed. So, if you go with 1:1, and assuming your engine is designed to run at 3600 rpms, then your alternator is only going at about 1/3 of its max speed. Not saying that’s a show stopper, though, since I don’t know how the unit’s internal voltage regulator deals with higher speeds.
But I do agree that you WILL need a governor. 10SI’s come in about 4 different current outputs, right? Which size did you get?
George Adams, who hangs out in the yahoo woodgas group has a nice simple throttle plate design for engines of this size. I thought he had published it somewhere, but couldn’t find it on his www.hayriv.com website just now. You might try to contact him there.
Pete Stanaitis
PeteS the Delco 10SI as originally designed have three wires. Each important for best overall control and battery life.
Obviously the bigger positive output wire. The OVERLOOKED case to mountings grounding side of the charge circuit to allow it to actually BE A CIRCUIT to work. Pretty painting and corrosion’s have undercharge many batteries!
Out the side of the unit the #2 terminal is supposed to be a large low resistance voltage sensing wire as close back to the battery positive terminal as possible. SO, the alternator will be driven up to whatever output voltage it is capable of to insure that the battery receives adequate charging voltage. Compensates for circuit aging building up resistances.
The out the side #1 terminal is more than just to run a charge indicator light. It is on-key powered to insure that the alternator/voltage regulator system get kick-started to charging at the lowest possible RPM.
Sure. Loop #2 to the output terminal. Then sooner or later bitch about undercharge battery.
Sure. Ignore #1. Leave it bare-disconnected. Most of the time the residual magnetism in the rotor metal claw pole will once the RPM’s spike high enough trickle charge to full start up past the resistance of the internal diode trio. Most of the time. Been many one-wires, ran and ran, at idle warming up, not charging at all without an engine RPM flare to kick it to charging start-up. Boats. School buses. Construction equipment. System charging starting up is properly in literature’s called “cut-in”.
Learn the terminals. Learn the circuits why’s, wherefore’s, to be in positive control.
Being clueless is just lazy-thinking. Lazy kills battery banks. Wastes fuels. Creates frustrations. Failures. Give-up’s.
tree-farmer Steve unruh
I have replaced aluminum mower flywheel with industrial cast iron style.
I have used the one wire alternator regulator but learned to appreciate the standard 3 wire version or build your own external regulator. I like the 22SI, looks more industrial and still produced. I should order a few more of them.
Hi Carl , on this engine you have got , do not bother fixing the recoil starter , just use a socket on a short extension on your cordless or electric drill makes starting so much easier than pulling away and trying to get the air mixture right all at the same time while huffing and puffing and catching your breath , oh thats me … sorry
Have you decided on your nozzle design yet ,are you going in the side of your drum/reactor horizontally or will you be fixing a vertical nozzle into the side or bottom ?
dave
That is smart - I wish I had thought of that. I will have to reconfigure stuff a little bit, and it will maybe stick up sort of high, but I see the advantage.
I did notice that the pull-cord jerked back on me when I was just playing around with it to see if it would fire on ether. The shaft seems like it is going to be much longer than needed to line a belt up with the alternator, so I might look for a large diameter pulley to stick on the end to give it a little more mass. Thanks for the info on RPMs as well, the alternator I ordered still hasnt come, but I am hoping it will come with some sort of spec sheet.
I got a 24 volt version that is rated for 50 amps. It is a single wire alternator. I am planning on running the output through a shunt so I can monitor the voltage/amps/kwh it is generating with a little multimeter. My battery bank is pretty small, so I am limited to about 30 amps of charging current. I have been trying to get my diversion loads all figured out - which in theory should allow me to apply 30 amps of charging current indefinitely without ever cooking the batteries - in practice, I am running into problems with the charge controller flipping out when it tries to go into absorb.
I have not really decided on the nozzle design, and I still need to track down a good reactor vessel. Part of me thinks this is a great excuse to buy that $600 slip-roller I had been thinking about getting… I had given some thought to the idea of a horizontal threaded pipe, a 90" elbow, and then either a cap (or maybe a plug would be even better) that has a 1/2 hole drilled in it. I could then just replace the caps as they wear out. I feel like a horizontal port would make lighting easier, but the general consensus seems to be that vertical jets are less destructive on the nozzles?
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Hi oregoncarl, yeah the engine start will kick-back, without any rotating mass like a blade or a heavy flywheel, soft aluminum flywheel key will often become sheared during engine testing when you have no rotating mass, the vibration of the engine while testing will be excessively intense…rotating mass fixes that. However once you get the alternator/pulleys/belt bolted up to the engine crank the alternator itself will give you a good amount of rotating mass, quite probably enough that the kick-back & vibration will not be as noticeable. The belt tension with the alternator must be adjusted fairly tight, any slippage in the driveline rotating mass will be seen as starter kickback/excessive vibration/broken flywheel keys…
If it is true the crankshaft is too long in your application, you can permanently alter the thing by cutting-off the excess length, but if you go in that direction, I would make sure to redrill the hole[blade bolt hole] much deeper to the depth of about 4.5" before you cut-off the excess length, in this way the [blade bolt hole] hole will remain after you whack off the excess length…as you might need that straight bolt hole to help hold the pulley on there. At best that engine model is a 5 HP on gasoline, as it is only a 12 cu. in. displacement, so additional rotating weight could be a very helpful thing as far as torque & engine smooth running goes. Maybe you can hang some extra rotating mass on that 3 5/32" shaft, if it becomes practical.
As for the PCV Positive Crankcase Ventilation, that valve is generally used to keep a ‘partial vacuum’ within the engine crankcase. That partial vacuum inside the crankcase is important, because it helps keep the engine from consuming excessive oil, and it helps keep the crankshaft oil seals from leaking, that PCV valve keeps the vacuum inside the engine, and pulses of air pressure come out the discharge pipe. So then where to plumb the PCV to? You could plumb it into your homemade fuel/air intake manifold, or you could vent it to the atmosphere [not the best air emissions result], but think about plumbing it toward your wood or charcoal hopper of the gasifier itself. Plumbing directly to the gasifier fuel supply hopper should reduce the PCV pulsating effect upon your system, & keep the emissions of it, incinerated.
As for the ‘Blade Brake Compliance stopping device’, on the front of your engine, yes that can be safely removed, by simply removing it, but ONLY because your changing the application, you are no longer intending to mow grass with a blade, your intending a generator, of which the BBC laws do not require such a stopping device [as far as I know]. The device can remain tho, as a practical ON/OFF switch, the heavy spring may have to be replace to a lighter duty spring, where you can actually work the thing easily. I would recommend you have an working ignition switch of some kind…to solely rely upon fuel shut-off is OK for a diesel engine, but not so much on a spark ignited engine. If you don’t like the BBC device on there, a simple ON/OFF toggle switch will give you the ability to control the ignition.
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My 2 cents question on this picture, or with other words, what am i doing different ?
I used to see throttle control between engine and T junction, hence doing my thing that way… now i see some different setup and i am wondering, was i doing wrong ? 
Good morning all.
I once was experimenting with a lawn mower motor pulling an alternator . To avoid the above mention kick back I attached a small car distburter to the lawn mower shaft.
With the dist I also used a 12 volt battery and the coil. The dist was attached to the shaft of the lawn mower motor just below the belt pulley with a short peace of flexible rubber hose and hose clamps.
I ran an insulated wire from one of the pegs of the dist and had a quick release to the spark plug. The time was set very retarded . I could crank the motor very easy with no kick back and after the motor was warm and running good I could switch the plug wires back to the original for running woodgas .
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So, if this is a “one wire” alternator, shouldn’t its internal regulator automatically reduce current as the batteries charge up?
I don’t understand why you would want to waste your precious woodgas by using “diversion loads” Besides, I don’t think you are going to have all that much engine power to spare anyway.
On another subject:
I saw your picture of your intake system with the iron pipe and the brass valves. All the weight will be hard on your intake adapter, due to engine vibration I think.
Since you are going to change your valving anyway, you might consider going with lightweight PVC valves.
Regarding the slip roll:
I see your point about getting one.
But, why not take your plan to a fab shop and have them roll that part for you?
I assume you’d want one that is will handle at least 36 inches of 16 ga mild steel. I don’t see any out there for much less than about $1000, so maybe you SHOULD get that $600 one.
Pete Stanaitis
I agree on re-plumbing to lessen the stress on the intake adaptor. If you decide to re-plumb, consider using gate valves instead of ball valves. Gate valves are easier to adjust for accurate air/fuel ratio and ball valves (especially PVC ones) are hard to turn creating more stress. Yes, you can get PVC gate valves. You can also remove seals from PVC ball valves to make them turn more freely.
Back to the EGR question. To prevent ashes from glazing your nozzles and to limit catastrophic oxidation of metal nozzle parts it is helpful to recirculate some exhaust gas to take the reaction from white hot down to bright orange. 900-1000C (1650-1800F) is about right. There is a long and interesting discussion on nozzle design here: Nozzles for Charcoal gasifier's - #320