Philip I didn’t know the reasons to move to Australia, but I am glad his family is safe now. Was his Chevy truck from his time in SA or does he still have it in Australia?
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Excellant report Phil vS.
Really shows us just how versatile and capable Patrick is.
A sad, sad commentary on the social aspects of base human natures though.
When the Believers of anything rise, and try to pre-dominate . . . time to move away.
He had, had a brother killed previously he had said.
My Wife and I are moving away from on both sides three generations of families local living for reasons too. 22 years now of less and less personal freedoms for us. More and more over-controlling you-must-now-do’s from them.
Steve Unruh
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Hi Cody, it was from South Africa. He told me that he’d driven it the 150 miles or so to Durban, and back again. He also had the same kind of 4.1 liter chev engine initially on a generator, but struggled to get any stability out of it. Specifically, his workforce understood that if they switched a couple of big motors on and off in quick succession Patrick would have to start the operation from scratch and they could have fun lounging around and watching him. 70 people getting paid to do nothing.
I do not think he still had the Chevy when I was there, his whole mission was to get himself off the very unstable and unreliable national grid. R 90 000 per month in electricity costs no more…
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Hi Steve. I commented to Koen about how much I enjoy this forum. Specifically, yourself being clear about what it means to be a scofflaw. Suits me well, that.
And Wayne telling me repeatedly in his videos “it don’t have to be pretty”. Helps me feel much better about my stuff…
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Once you are into diesel engines your already at very high compression ratios and very small returns trying to get more efficiency out of higher.
An increase from 5.5:1 to 7:1 on a low compression engine is a huge deal.
You will see fuel burn drop.
17:1 to 18:1 will just put more stress on bearings and internal components.
The fuel saving might not be enough to even justify the cost of modifications and it may well shorten the life of the engine.
Ill go even further and say the engineers at Lister probably designed into that engine the lowest compression ratio practical for easy starting and clean operation.
Trying to improve on something like in a non emission engine already is real hard to do.
But flip that argument on its head again.
DW. Onan set the compression on the CK engine at around 5.5 :1.
This was done because 80 octane gasoline was common and cheaper than higher octane gasoline. ( a cost effective compromise )
But they also made high compression heads for the CCK-B and tractor applications.
This is where you would probably want higher octane gasoline and the small increase in load was not as serious on the bearings as compared to the performance improvement.
So a high speed variable load engine or stationary engine running natural gas would get the high compression head.
Any more than that will not help you much even it your only at 7:1
Case in point this…
I made a higher compression head for an LK 205 and tried to get more out of it than the original low compression or high compression heads could offer.
I gained nothing.
The lesson was the engineers had a pretty good idea what the design was best for ( and this is especially true of a stationary application )
Overhead valve engines like clones ( lots of people are interested in them around here ) are cheap.
And they have a less than optimal compression ration too, and like the older CK engine they were designed to burn low octane (87 ) gasoline
You can pump those numbers up to 10.5:1 very cheaply and easily with bolt on clone parts.
You can go higher with more parts, and more money but is it cost effective?
DO you really want to start looking at a Billet rod with a better bearing to compensate for the increased wear? ( and does this pay for itself in higher efficiency ? )
Or is it cheaper to keep things simple.
To get the kinds of performance increase in the HR you would get from the LK going 5.5:1 to 7:1, and the clone going from 8:1 to 10.5:1 you might need to go to 20:1 on the HR.
Then the law of diminishing returns comes into play.
Did you get any real improvement at all?
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Thanks Wallace, simple is better. What I was wondering is, if the CR of my Lister is not to high. But we will see. The best is finish this project and finally move on to woodgas.
Installed a mufler last weekend but the engine itself is still very loud. Eventually it will be packed in a room. No detonation heard then.
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If you are trying to draw a mixture through a carburettor that is correctly mixed for ignition then there is always the possibility it will ignite in an unpredictable way when drawn into a diesel engine.
The reason diesel works at all depends on two factors number one the fuel is never delivered to cylinder with air like gasoline engine and two that it is delivered at the right time and it auto ignites . ( there are other systems that do mix and alter these two points and they are not good efficient engines by modern standards )
Two factors that work in wood gasses favour for a diesel are high octane ratings and the need to burn at 1:1 ratios.
If you draw in woodgas at a rate less than 1:1 its unlikely to ignite at all under heat and pressure.
Its also likely to burn cleaner with less soot and less emissions if the right minute can be found.
At low loads your going to waste gas, it will be to lean to burn properly and there is not enough diesel inject to force the issue.
At high loads however you might safely manage to displace 50% of the diesel fuel injected ( some will say more, but you have to do things to achieve this like alter timing).
SO.
if you can tune your lister to draw close to a 1:1 ratio of woodgas at be you will not have enough oxygen left to run pilot fuel.
If you run run 1 < 1 parts woodgas to air you will have enough left over oxygen to run pilot ignition and still burn all and use all the oxygen to burn fuel.
This is tricky stuff…
You need a way to introduce un-throttled air with a variable amount of woodgas at the higher ends of the engine load to ensure you burn all your fuel.
I have no idea how to do that without a computer.
Or you could just wing it.
Lock your injection rack at some point from opening further and using a gas mixing carb to deliver a lean but fixed mixture to the engine.
And you want to do this while never going rich or " Anaerobic " in diesel jargon…
Good luck with that.
Not that its impossible, that’s not what I am saying, its just going to be tricky.
You can still displace a significant amount of diesel fuel if you are not able to keep the systems lean and perfectly mixed at variable rations to load.
Its juts not going to be as efficient as it could and you are not going to be able to get full power from the engine ( without a turbo that is )
You going to have to run a lot of tests
Find out what works best
Also all air cooled engines are louder than the liquid cooled because of their construction.
You hear more mechanical noises from them, thats just life.
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Joep, as far as I have experience with diesel engines, I think your Lister with direct injection cr has somewhere around 1:16, that’s the ratio most manufacturers used at the time. Of course, this ratio is adequate, but otherwise the capture of air and gas is somewhat suppressed, which reduces this ratio, but as for the mixing ratio in a diesel engine, it is slightly different than in a gasoline engine, and otherwise much easier. The air is somewhat muffled and the gas valve opens all the way, i.e. full power and a ratio of 1:1, but when the load decreases, the gas valve only closes, and this activity should be performed by the rev regulator in parallel with the diesel fuel regulation. In my tractor, this is done by the vacuum membrane and the EGR valve flap, which I have already posted, does not work perfectly, but quite well.
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Thanks Tone, I still think diesel is the underdog. Very easy to set up ( in my head). It is for a grid tied generator, steady load.
Thanks.
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Oh ya once you are on the bus and can adjust your fuel mix under steady load your laughing.
But to do this on the fly with two variables changing mixture and load, man your busy fidling with adjustments.
This video shows some adjustments on a JD tractor with a Turbo charger.
NOT the same as the HR by any stretch but the Aneroid valve is interesting.
It limits fuel if there is not enough boost to burn it all.
This is kind of like the problem on the woodgas/diesel engine.
If a mechanical contrivance could be made to allow a an injection pump to back off on the fuel as the amount of wood gas increases in response to pressure drop across a gasifier it might make an improvement in fuel efficiency and economy ( also no black smoke )
Sounds like another Arduino problem and some more PID stuff
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Wallace, to understand the ignition of fuel in a diesel engine, let me say the following, diesel fuel ignites in contact with hot air, which is heated due to high compression, this temperature is approximately 400°C, well, at the moment when a small amount of diesel fuel ignites, this temperature increases considerably (at points it is very high), which ensures reliable ignition of all combustible molecules in the combustion chamber, even if there is a large excess of air. With an excessive amount of gas, of course, black smoke appears, as with the use of all other fuels, but ignition will occur, because with a rich ratio, we still get some oxygen into the cylinder, and the temperature during compression remains the same, and ignition is guaranteed. try it out. Joep, if the load is constant, you just throttle the air and open the throttle and it’s…
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What will happen when the engine sucks in too much woodgas? How will you prevent a runaway when you produce too much gas? The fuelpump should close the diesel apply, but the gas will combust and rev up the engine I guess?
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Koen, if the cr is 1:16 or less, wood gas will not ignite without a spark plug or low octane fuel (diesel fuel), so the moment the diesel pump regulator closes the supply of diesel fuel, the ignition is interrupted and the engine loses power, despite a strong mixture of gas and air, but it is still good to have a lever installed that closes the gas supply in parallel with the diesel fuel.
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Yes I understand Tone.
I guess what I need to do is draw some curves to explain myself.
Its not the first time I post something here that does not read easily for people to follow
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Okay that makes sense, I will figure out what engines are 1:16 or less. Modern engines go 1:20 sometimes I think.
A controlled valve for the gas mixing would be a good solution in this case. What about the gasifier, do you install a kind of pressure relief valve in case the valve to the intake is closed? And how to controll the amount of gas you produce for the engine? For a stationairy engine with a constant load it should be easier, but what if your tractor is idling for about half an hour or more?
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Koen, when the tractor is working with a small load, I usually throttle the air intake, so the engine sucks in more gas and keeps the gasifier warm, the mixture is so rich and the ignition of this mixture gives a strong thrust in the engine, so the diesel fuel regulator also shuts off the diesel fuel supply at intervals, so the entire amount of gas is not burned in the engine and part of this gas is lost through the exhaust, … well, Koen, to make a wood gasifier that would work stably both with low gas consumption and with high gas consumption is a great art, that’s why everyone here we try and test various design solutions, but when using it, each of us determines the limits of the minimum and maximum amount of gas produced for our gasifier.
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I can imagine it is much more complicated to adjust an engine with a variable load. No experience yet, but a stationairy engine like a generator set looks more stable to me, even if the electrical load varies.
Another question; will it be a good idea to use a marine engine so you could use a waterbuffer to cool down both the woodgas and the engine? Using a radiator causes heat losses that I could use to heat the workshop and house. I want to build a new barn with a woodchip boiler and buffer tanks to avoid excessive gas bills… But if a gasified generator can produce electricity and heat up the buffers it could be a good replacement.
Fortunately the energy contract for coming year is not variable, good news with the nord stream issues… So for this winter I won’t have big issues.
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Koen , water cooled marine engine with exhaust cooling , water cooled gas , …ideal case
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Now you are starting to understand the problem
That zone from 25 to 50 percent is the best area for Diesel substitution of wood gas
Bellow 25 a significant amount of wood gas would be too lean and without enough pilot injection.
Above the 50 you need to reduce gas and increase fuel to keep the injector top cool and get the area power you need for heavy loads
But in the middle where you do most of your work most of the time you can displace a significant amount of diesel fuel
Fat line is power demand
Skinny line is fuel demand
Clear zone is Diesel fuel consumption
Cross hatch area is best use most efficient area of wood gas combustion
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Cell phone just awful to use for this sorry fellows