General Motors Svedlunds Gasifier

Pontus · April 10, 2018, 3:37pm

Hehe, in Sweden we have a saying, swearing in church… when you do or say something highly inappropriate. I believe I might have done just that with my last post.

I’ll fix some photos for you the next time I’m out by the farm. Might take a while but you’ll get them sooner or later.
I have a 1964 IMZ(Ural) M62 with a drive line from a later KMZ(Dnepr) motorcycle. 650cubic centimeter engine, boxer lay out. With the original sidecar it weights around 350 kg without passengers, spare wheel and so on. The hauler sidecar is lighter, it only weights around 90 kg.
This bike I have now probably won’t be running on charcoal in the future. I intend to get another one, and use that as a experimental frame, ethanol, wood gas and so on.
Tilman, funny that you mention those vehicles. This bike is just like those two. Different models, but much the same! Have a some pictures of the Ukranian KMZ you mentioned.

These are not my picture, I hope that’s alright, they serve as inspiration. All of these bikes are based on the same platform. My hopper is roughly the same size as these ones.
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Pontus

taitgarry00 · April 11, 2018, 5:06am

Are those all restored historical machines, or has there been some reinvention too?

Great examples. There’s no historical equivalent in North America.

I’m not a big motorbike fan, but I would gladly ride any of those.

Til · April 11, 2018, 6:28am

Hi Pontus,

I had exactly the bikes you show bikes in mind
So your a Ural-rider? How do you like it? I ask because I often thought about buying one years ago, but instead I bought a MZ TS250, built 1975. Also with sidecar. Nice little bike, but with a 250 ccm two-stroke engine not the perfect base for powering it with charcoal.

I know also 2 youtube videos of the Dnepr. I just post the link in case you don’t know them already.

Regarding cutting the original gasifier: Sure I would hesitate to modify something historic. But the main thing is that I just assume that the Svedlund gasifier is bigger and heavier than necessary. The hopper is not the main issue, but the hearth zone could be too big for a comparable small motorcycle engine. That would lead to lower quality gas.
I guess all the pictures above show wood-gasifiers. With charcoal, you can build more compact and smaller.

Anyway, looking forward to see your bike!

@taitgarry00, the history of the the Russian Ural and Ukrainian Dnepr is much related to the BMW-motorcycles. In a nutshell,they started to copy them for military purpose just before or during the WW II. Before the Nazis attacked Russia, there was a cooperation between both countries. After the war, they just kept on building them with relatively few modifications, so they looked very classical and still do today.
The motorcycles in the photos are all modified later, not during war time. There are many woodgas vehicles in eastern Europe and Russia, but due to the language barrier I nearly know nothing about them. Just stumble on youtube-videos from time to time, but can’t understand anything…

Regards,
Til

Pontus · April 11, 2018, 10:33am

Truth to be told, I’ve ridden my bike once. I felt there was huge hole in my experience pool that needed mending, I had no clue on how to wrench, so as a response to this I bought this bike, sight unseen, 940 km away. It needed a lot of attention and that was exactly what I was looking for. After a month I had it running, took it for the one ride, and then disassembled everything. Now I’m slowly rebuilding it onto a “new” road legal frame.

To sum up these bikes constructions. They are simple, they are robust in some aspects, weak in others. With after market parts even those weak spots can be smoothed out and you can get quite a reliable machine. If you are unlucky you can get a horrible example, some of the machines that came out of the factories in the desperation of the 90’s is crude to say the least… but hey, we are not doing it because it’s easy.

Except for the IMZ and KMZ there is also Chang Jiang(CJ). When the Soviets went on with newer models they sold the old equipment needed to produce the first model, M72, to the peoples republic of China. They’ve basically produced the same bike since then, with a couple of upgraded models as well. With other words, these bikes have been in production since around 1941, the amount of spare parts and after market stuff is immense!

As I said I’ve only ridden my bike once, but last summer I made my way through the Baltic States by jumping between my friends sidecars. Had a great time, riding slow, riding good.

Cool! I love the square shape of the MZ cylinder cooling, I’ve been wanting to get some kind of MZ as well! Tell me about it, did they often come with sidecars?

But back to the hopper stuff!
Tillman, the lower quality gas that comes from the to large heart zone. Is the problem that the hearth doesn’t reach a high enough working temperature which results in a higher amount of impurities?
But yea, it sounds like it might be a good idea to make something a bit more compact. Maybe I should just patch this one up and use it as a test platform to get a better understanding for the basics of the process.

By the way, engines designed for unleaded fuel. Will I have to use a lead substitute while running on wood gas? I guess that would be the case but what do I know.

Sorry for the bike rambling folks.

Til · April 12, 2018, 6:22am

Hi Pontus,

the MZ are quite often equipped with sidecars, because you could order them with that readily in the shop till the end of the production early in the 90ties. In the GDR where they were built, they were a daily-driver not something to show of. So they are easy to maintain and repair, low cost to ride but no fancy design and relatively weak and slow. Still a high number running and available and lots of affordable spare parts. Used mine as a daily driver instead of a car the whole year round without any problems after I overhauled engine and gears, which is not more difficult than a moped. Just a bit larger. Weak point is the little 6V dynamo and ignition, but nowadays a larger 12V version and a pointless magneto ignition are available. With that you always have a strong spark and no start difficulties, even if your battery is low.
You love them or you hate them. I guess similar to IMZ, KMZ or CJ

Sorry, enough off-topic now.

Well, depends if you go for wood-gas or charcoal-gas.
With wood, your hearth has to be exactly the right size for the engine, otherwise it won’t work at all. Too large hearth might get flammable gas, but lots of tar will gum up the engine soon. The right hearth dimensions provide enough heat to crack or decompose the tar.
Too small hearth runs too hot and will deliver weak gas.

You have a Svedlund gasifier. This is for charcoal, as far is I know. A picture of your gasifier inside will show it. You can also compare it to the description of the Svendlund gasifier in this book http://www.driveonwood.com/library/gengas/
page 102.
Charcoal has no or only traces of tar in it, so hearth size and temp are not so critical. In the case of inferior charcoal it should however be hot enough to decompose tar traces, that means not too large. More critical is the air velocity at the air nozzle. Koen advocates 25 m/s at full throttle. If it’s much slower, the temp will stay too low with the result of low quality gas.
As I said, here the dimensions are not so critical. Often charcoals gasifiers were built in three sizes: Small cars (lets say 1-2.5 litre displacement, medium for 2.5 - 4 litres and for larger cars more than that).

So I guess yours is made for a car sized engine. It might work on the bike, but not ideal. Try it, but if you really want to run the bike with it maybe build a smaller (and lighter) version is the best idea.

Lead substitute: Well, there was nothing like this during the war. An engine will run without this. Maybe the valve play has to be checked a bit more often to be sure. In a german Classic car magazine they made a long term tests with two cars of the 60ties, one running with and one without over several thousands km. They didn’t noticed anything which was above normal wear in the engine without the lead substitute.
Your bike has the ohv engine with aluminium head, right? So it should have steel valve seats anyway and lead substitute is not really necessary.

Regards,
Til

Pontus · December 2, 2018, 2:26pm

Alright, long time no see. I’ve not given up, I’m just taking the long way around. Say hello to my “new” engine:

I bought this soviet MT801 for two reasons. I felt the need to learn the basics of a simple engine’s internals, and I wanted a “clean” engine to run gasifier testing with. If something where to break down or misbehave I wanted to be sure it wasn’t because of wear from the engine’s previous life. I’ve taking everything apart to check the condition of things and to get a better understanding for how stuff works. I’m trying to allow myself to take the time I need to get a good feel for it all, I think that’s the hardest part so far, it’s easy to rush things.

Today the engine is completely dismantled and I’m just about to start putting things in place again after some repairs and improvements where it was needed. Not much to say about the engine otherwise. It’s the first OHV-engine of the KMZ factory, introduced in 1967, made for 6 volt DC generators, producing 32 horse power… in theory. Two fun things, it has manual ignition advance and a centrifugal oil cleaner. The later is installed directly on the crankshaft which results in the fact that nobody ever cleans them out. You can imagine the amount of crud I’ve been scooping out of this machine, not a pretty sight. Most of the time spent on this engine so far have been spent on cleaning… lots and lots of cleaning.

I don’t know anything about her history. I contacted a dealer I’ve visited before in Estonia and told him “Hi, I want to learn engine renovations, give me the worst klonker you have, as long as it turns over whatever you send me will be ok”. He sent me this, and it did turn over, about three centimeters until the piston hit the wall of rust that had formed on one of the cylinder walls. And as you can see on the last picture, there is a hole in the cylinder head. Might have bumped a rock or something, who knows?

But that’s about it. We’re still on the move, we would probably lose in a race against a turtle, but still moving non the less. Take care folks.

pepe2000 · December 2, 2018, 10:11pm

Hi Pontus,
Wow, kinda reminds me of my 1969 VW Karmin Ghia days. It was running on 3 cylinders. I took my engine totally apart (my first ever engine rebuild). Ran so sweet when I was done.
I put another 100,000 miles on it, sold it to a friend who put another 75,000 or so on it and sold it
to another lucky guy. One of the toughest cars and engine I’ve ever owned. Solid!
Looks like your cylinder top has the hole, they should be replaceable (so to speak as they are replaceable
in the VWs). Keep us updated.
Good luck.
Pepe

madflower69 · December 3, 2018, 2:29am

I didn’t find much about the gasifier. But apparently GM was sued for patent infringement in 1943 by the gasifier mfg. company. Apparently gm was using a model t carburator and it was essentially a duplicate design. I can only assume this was for a US truck. I think there might have been one in the Walton’s TV show.

I also ran into the Coal turbine cars of the 80s which are begging for charcoal.

In free piston lingo they had a component called a gasifier.
https://macsmotorcitygarage.com/video-gms-xp-500-free-piston-car/

madflower69 · December 5, 2018, 4:59am

For those still waiting for the Firebird III, and want to make a test model. This might be a good start, some serious bonus points if you get it to run on char/wood gas.

taitgarry00 · December 5, 2018, 9:44am

I’d say serious bonus points if you can get it to run at all… There’s an obsessive level of work in that little project. A pulse jet looks like a weekend romp in comparison.

madflower69 · December 5, 2018, 4:59pm

I think you should try. I can probably get the 3d printed parts and possibly a 6mm rod from an old printer and send them to you. But I don’t have a drill press, one of those fancy dancy stepped drill bits, nor any metric tap/ Besides this project really needs some of those fancy dancy Robinson screws which are unobtainium in the US. They used phillips, what were they thinking?

taitgarry00 · December 5, 2018, 6:18pm

I hear you, the Robertson screws would give a person an edge.

I have been amazed by those mini jet engines, some designs used wood laminate for the compressor fan.

Any way you look at it it’s just a beastly amount of work. With a lathe it would be far simpler, balance will be critical at 25,000 rpm.

I’d rather burn propane in a pulse jet. I like the hydroform approach, but any method seems to give a maximum "bang for your buck "…

Edit - come to think of it, the hydroforming technique could be a good fab option for various wood gasifier components…

madflower69 · December 5, 2018, 7:06pm

They 3d printed a lot of the parts and the forms for the blades, so it isn’t nearly as much work.
A lathe would make it a lot easier.

I don’t know if it would be or not. Did you see all those leaks at about 1:16 in the video? It is almost as holy as my welding.

taitgarry00 · December 5, 2018, 8:23pm

The beauty of the hydroforming is it doesn’t need to hold perfectly, just momentarily. And you will know where every pinhole is, no doubt. Grind, dry, repair.

madflower69 · December 5, 2018, 11:22pm

That is a great point for most people! However, my holes are actually pen holes, more akin to the big fat sharpie pen size. I don’t even need glasses to see them.