hi don
yes but you need a second butterfly or some way to add restriction you could use a blower but then it would fume you a low power I have a 24hp yanmar that’s what i’m building my 8" WK to run
if you have any gasifier just stick the hose up to the intake and experiment with it
however depending on the model the new ones will shut the idle fuel off at about 1400 so you would have to give it a little throttle just to give it idle fuel at high rpm"s i don’t think you could run full rated power for it may knock but i have only run mine full power 2 or 3 times in the 30 years i have owned it sometimes i run full rpm’s but almost never full rack
good luck
Tom
Hi TomM.
Is your 30 year old 24hp Yanmar also a 3T90J like mine perhaps?
Regards
Steve Unruh
hi steve
I think it is a 240D
It’s a twin cylinder it’s not fancy but i would be lost without it
I probably won’t run on wood gas all the time but just wanted to have it in a pinch It doesn’t use much fuel anyway
Tom
What about using a Powerstroke diesel engine to sit stationary and run a sawmill? We have an extra one just sitting around doing nothing right now. We took it out of a Ford Superduty and put in a Cummins instead. De-stroked the Ford. 
Works good, too! If the engine is just sitting under a shed and not in a truck, would that take care of some of the issues? What about using used veg. oil with the wood gas instead of diesel? Running a bandsaw isn’t going to be as bad of a load on the engine as having it in a truck with a full load of something…right?
Hi Clarence,
Diesels are harder. It’s not an issue of the load on the engine, or any additional complexity with the gasifier. The only difference is controlling the engine. You need a source of ignition, either a small stream of diesel as a pilot, or convert it to spark ignition. These are both non-trivial for the beginner.
Also keep in mind the compression ratio. Some newer engines run very high, around 22:1. Above 17:1 the woodgas will detonate, which will throw off the diesel’s timing and make it run very rough, even damaging the engine. The compression can be lowered using thicker headgaskets. Again non-trivial for the beginner. But it can be done.
Veggie oil will not make any difference to the woodgas, however it has its own issues for cold starting. I’d stick with plain diesel for the pilot stream unless you know exactly what you’re doing.
hi clarence Yea if you shoehorned the cummins and got it in there you have a good engine the slang is power JOKE although i did much testing on IH power strokes that is the 7.3 the 6.0s are boat ankers but the 7.3s were very durable but not the engine of a B cummins
I think if i can remember right the P strokes are about 17 to one which is about as high as you can go
As far as complexety it’s pretty simple i’m in the process of digging out the paper work on it as soon as i find it i will post a diesel on pilot injection is really very forgiving on mixture way milder then spark ignited
but you still have to use some diesel
Tom
It seems like a OLDER 5.9 cummings with the mechanical injection and a 17 to 1 compression might be a Good choice?
Would it be a even simpler convertion? Ive read that it takes only a 5% pilot injection to make things ignite But how is the engine power governed/ do you ALWAYS inject the sameamoount of fuel in each revalution and control power with woodgas restictions? Do you have to make the amount of diesel injected bigger and smaller to control RPM?
Hi Rodney
You still need to use a throttle if not when it hits the gov it will stop igniting and when it slows down and relites it will be like turning the key off and on in a gas engine GOOD engine to convert much tuffer and better torque then a power stroke
good luck
Hmmm. Let me expand on this a bit.
Dedicated diesel you do NOT have to control an air to fuel ratio for even steady combustion. Woodgas fuel, like gasoline you do.
Too much air for the amount of woodgas fuel pushed or sucked in and it will not lite off with either a diesel pilot ignition or a spark ignition. Lean miss-fire.
Not enough air for the amount of woodgas pushed or sucked in and again the woodgas fuel will not lite off and in the cylinder combust. Rich miss-fire.
In both cases the unburned woodfuel gas and air will be pumped out the exhaust not yet combusted.
The deisel govenor if still active will rack up more diesel flow to try and maintain power and RPM. If diesel rack is limited engine will lose lots of power/RPM and may even die.
This is one reason why once you are primarily fueling with woodgas you would have to control the air to the actual amount of fuel gas inducted. Or visa-vesa. And the combined system better be good, and able to control now the diesel, woodgas fuel AND the air through all operating conditions.
Those who have done this report a big problem with engine run-a-way speeding up with sudden engine load releases. AND with engine load changes like generator load shedding, or in a manual transmission, having severe back firing out the exhaust.
Sorry. Not going to be easy and straight forward like methane and propane fumigation fuel supplementing a running diesel. These are both respectively ~5X and ~10X as energy dense as woodgas and pure hydrocarbon fuels. Not nitrogen and carbon dioxide diluted like woodgas fuel.
Methane and propane are both PRESSURE supplied to the engine.
Most woodgas producers are built for carbon monoxide safety purposes to be engine sucked contiously.
Diesels do not suck. Why they need to have supplementary vacuum pumps for the power brakes and climate controls in the pickup and van chassis installs.
So to retain the woodgas system suction flow you must convert your diesel to a suction engine.
You do this by controlling the air to create intake manifold vacuum.
2nd reason you will have to actively now control the engine air.
Regards
Steve Unruh
I get it. as deisel fuel sprays into the cylinder It isnt combined with ALL the air there just what it meets in the area of the injection so at some point there is the correct mixture and at others no fuel at all and thus the extra AIR is"Invisable" to the fuel mixture.
Wood gas on the other hand wouldnt be injected in a compact mass it would be more or less mixed thru the whole cylinder…
Id think it would be best to run woodgas a bit lean so that the pilot diesel injection finds a LARGE areas as possable to induce the correct combution ratio.
for instance a small injection into a cylinder filled with wood gas might be the proper amount to burn 25% of the wood gas a larger one might be enough to cause the proper ratio to ignite in 50% of the wood gas. and so on…
It woul seem that tp do this with the diesel pump controlling the process it would require a VERY consistant woodgas to air mixture and would waste a LOT of woodgas?
Hi Lewis
Yes more or less when i worked for the gov in research it took me awhile to get a grasp on it
A phd at MIT finally got it through my head all the years as a mechanic i always thought combustion was combustion boy was i in for a surprise On a SI engine the mixture has to be at a close ratio so when the plug lites it the flame burns on a micro thin layer through the charge On a diesel the cyl is full of air preheated to about 900 to 1050F.Diesel will lite at 760 to 900f or so as it is injected it burns a diesel really needs swirl if not it will smoke bad no matter the boost
When you pilot inject you have a charge of wood gas heated to the 900-1000 or so So it will not burn but whenyou inject a little diesel into it the diesel ignites and then ofcoarse the combustion event takes place
it can be taylored by how much fuel and how deep into the charge it goes the temps i gave are just ball park to many things very this to list here
MIT has a very good book on this if you want to get deeper into it
Without getting bogged down in details once you do this it becomes an SI engine only with a shot of fuel instead of a spark so then you have detonation worrys just like a SI engine Detonation is not fully understood but it happens when the flame front advances across the chamber it squeezes the mixture to the other side if it squeezes it to hard the temp will get high enough for it to lite then you have two or more flame fronts moving towards each other the gas in the middle gets squeezed so hard it more or less becomes plazma and you know what that does to metal
Sorry to string on so much but it’s pretty involved
I will post that MIT book title so if anyone wants to get it It’s a really good read
Good luck
Tom
Hey Lewis
I should have mentioned the o2 temp factor
The pilot fuel really just gets the chamber temps up to lite off for the charge
On our hcci compression ignition engines where we have ample compression temps fuel ratio goes out the window if you have an o2 rich enviroment at or above the ignition temp of the fuel regardless of what fuel it will combine with the o2 or in other words combust we had good test equipment with press tranducers and thermocouples in cylinder to prove this and even the smallest amount of fuel will combust in that enviroment
But as steve i think said you still have to control it or it won’t be useable
somewhere in the premium section i posted a simple diagram of how to do this It does work but it’s not turn key takes a lot of work to tweek it
good luck
Tom
This is what helped me understand how diesels work vs gasoline or woodgas. Bear with me as I know it’s way oversimplified.
ALL fuels have a temperature when self ignition begins. Diesel is relatively low, Gasoline is relatively high. Woodgas even higher. When self ignition happens at the wrong time, it’s called knocking or detonation.
When you compress FUEL to a certain temperature it will self ignite. Compressing air doesn’t have this effect, since it’s not flammable.
A gasoline engine compresses FUEL to a temperature just BELOW the auto ignition point. A spark then begins ignition. Many things can throw off this delicate balance and cause knocking, one being a very lean mixture.
A diesel engine compresses AIR to a temperature far ABOVE the auto ignition point. Fuel is injected at the right time, and instantly self ignites. Lean mixtures are no problem, they cannot cause detonation because the fuel is not present yet. Therefore a diesel does not need throttling, the cylinders can always be filled with air and the only variable is the amount of fuel.
When you add woodgas to a 22:1 diesel, you are compressing woodgas FUEL to a temperature ABOVE the ignition point. It will knock, same as gasoline. The explosion of the gases is no longer under control, and happens too early.
When you add woodgas to a 17:1 diesel or regular gasoline engine, you are compressing woodgas FUEL to a temperature BELOW the auto ignition point. It is ready to be lit, either by burning diesel (which ignites at those temps) or by a spark plug.
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Very well put Chris
I found my mit textbook but i need to find the publacation #
I had forgotten how dizzy it made me trying to read it LOL
After all i’m a red neck it was a real chalange in the PHD enviroment but fun too
Tom
hi tom
i started this discussion and thanks for the comments , but never did see any paper work or diagrams.
Diesel engines run by compression - no spark - the compression stroke at near 20:1 produces 500-750C near instant gas temperature - then diesel is injected - it is going to combust when the diesel is injected !!! Wood gas along with the atmosphereic air with a high compression engine and it will autoignite. How much compression? I do not know today. BUT you will still need diesel for lubrication and basic startup combustion etc Start on diesel then add wood gas. So plan on something like 20% diesel and 80% wood gas during operation. Plumb your wood gas flow regulated (good meter) to your diesel air cleaner body… I believe the best way to monitor the combustion is by Exhaust Gas Temp (EGT) guage - add a known wood gas flow rate and see if the EGT detects the change in temp - watch for autoignition - too much wood gas - the EGT temp drops etc… burning BTUs input means your diesel is doing work. Check your diesel manufacture for EGT limits. There is a limit on how much basic engine compression before the compression stroke produces to much heat and the wood gas will autoignite - what is the optimum or upper limit for diesel compression ratio to use wood gas? My International DT466 manual says this engine is 17.5:1 compression - time will tell - anyone with a portable wood gas system wishing to visit and test - let me know. Maybe others have already experience - What say you?
Here is a video on Youtube with a Perkins 6-357 diesel running on wood gas: http://www.youtube.com/watch?v=ilIENTm5muo&feature=related
Ah good you found this DouglasP.
Welcome abound the good lifeship Woodgas.
If you put Diesel Engine in the Search box on the LH side bar you will also bring up over 15 other topics where this has been touched on.
Woodgas fuel supplementing of diesel comression ignited engines has been done a lot going clear back to German government and industrial and bus/truck big 2-stroke engines back in the late 1930’s.
Pictures of this in the WWII Gasifiers section here.
Most recent documented work has been in India in the 1980’s into the 90’s. Some obscure Chinese research out there too. Before these there was some government sponsored well documented dedicated work in Sweden with a farm tractor and a delivery truck. Some 3-4 year to last year recent down in California at All Power Labs location work also.
You are correct that fuel(S!)/air/speed with variable loads controlS has proven to be the most difficult problem.
When done because of heavy oil fuel shortage abandoned quickly when those fuels became available.
With a diesel fueled cycle you only have to control the fuel quantify and the timing of the fuel injection.
With a spark ignited gasoline/propane/methane/woodgas fueled engine you have to independently control the air, the fuelgas and the timing of the spark.
Woodgas supplementing a diesel compression ignition is not like relatively easy fogging in supplemental pure dense refined 100% HC propane or methane. Woodgas at best only has 40% of the composite fuel gas as combustibles - the rest is inert gases and free soots.
Woodgas as an 80% fuel component you then have to individually now control the air, now TWO different fuel streams and the diesel injection timing.
Because of now compression limitations to 17 to 1 for the woodgas fuel so it will not pre-detonate AND now the engine having to suck against an air throttle restriction (have to now control the air for the woodgas useable A/F ratio AND create a suction to pull the woodgas through the hearth and filter rectrictions) you just lost two of the three reasons diesel CI engines are more efficient than SI engines.
The India developers found that they could elaborately vacuum/mechanically set up systems to control all now FOUR factors. Later they did this electronically. Thier biggest problems reported were damaging engine run-a-way overspeeding (same found at APL) at engine load shed off conditions (large electrical consumer suddenly shutting off and transmission shifting points) along with severe damaging exhaust backfiring.
Later still you can see the lightbulb went off and Cummins-India and the Practash engine companies there just started suppling compression reduced, magneto and ignition distributor diesel based block converted engines for dedicated woodgas (“Bio-mass”) and methane (“Bio-Gas”) useage.
Then back to only three factors to control.
This is how the industrial IC engine company Jenbacher/GE had done it all along.
Oh yes. In the past 4 years I acquired two different specialized diesel engines with the sole purpose to woodgas 80% fuel them on a CI. Then I correspond and read of those who had done it, thier problems encountered and work-a-round solutions. Too complex. Then planned out spark converting them. Still too complex and a shame to waste of two fine diesel engines. Just went back to normal IC spark ignition engines and no longer have to worry about trashing an expensive, hard to replace injector pump and onjector from too low of cooling liquid fuel flow. The problem the Swedes had on their engines after a few hundred hours. And now I can multi fuel on gasoline, propane and methane also.
Regards
Steve Unruh
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I was trying show the little VW running on wood , Maybe this is it.
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Hi Jim
Sorry i must have forgot you
The manual is MIT professional edu.program
date is july 2004
coarse #2.615
If you can’t find it send me your mail address and i’ll ship this one to you
I probably won’t use it any more if i go back to the gov I’ll have to get a refresher coarse
It’s pretty involved it explains the reason some CI engines have more compression then others
small bore/stroke engines loose more heat thru the walls and head so it may or may not really have more heat it’s not a one rule fits all
Anyway your welcome to the manual
Sorry again i forgot to respond
Tom
Hi Jim
Did you ever get the diesel to run on wood gas ?
Thanks patrick