Excellent effort all around Ray. GA.

Discuss Brakes issues

Discuss Wheels & Tires issues.

'This ones for you Garth! ' (< 8)

A Foldable Electric Bicycle for Your Urban Commuting Needs

The YikeBike mini-farthing zips along at 12 mph on a little electric motor

Discuss Engine & Motor issues.

All,

another crazy idea... I must be getting notorious by now.

part of the reason I've not been available less the last couple of days.. and not doing what I'm supposed to... is I couldnt get this idea out of my head... so I'm about to post this to the "Modular Vehicles" thread.. but thought you might want to see the larger versions.

It is incomplete.. but represents 2 days of modelling for what you see. the valving mechanisms will be next. then intake, exhaust, fan, shroud, etc. etc. etc. etc...

basically, it is a modular engine. 2" pistons.. so the first part that is modular is the number of pistons. If you want to have a 3 cyl, just blank off the other positions. (no conn rod, piston, cyl, etc.)

the next modular part is the fact that you can stack units together.. creating 6, 12, 18 cylinder engines.. hopefully you can see what I'm talking about.

obviously there are a few details missing and solutions required.. but I think its all fairly standard stuff.. just the 'modular' part is unique and subsequent layouts... I'm still pondering intake and exhaust modularity.. but I'm hoping some of you all will take an interest and give me more ideas. (sketches on whiteboard ?)

hope you like this one... but if not.. oh well, there is more where it came from.. a deep well of craziness..

Chris

Less parts - continious motion (no reciprocating losses) - more HP - more compact - no valve HP drain - twice the power per swept volume.

Single "cylinder" 1 40A

It is of note that

In auto racing, the displacement of a Wankel engine is usually doubled for classing purposes.

I.e. a 1.3 l is "judged equal to" a 2.6 l conventional piston engine.

Thank you Kyzine,

All.. Kyzine has also pointed out to me that these radial engines have odd numbers of cylinders so that the cylinders can fire in an 'every second cylinder' style, and keep the cycle running in an endless loop.

and here is his links. (sent to me in email)

http://en.wikipedia.org/wiki/Radial_engine

http://en.wikipedia.org/wiki/Radial_engine#Multi-row_radials

http://en.wikipedia.org/wiki/Warner_Scarab

My only defense of my design, in light of all that you have shared, is that I feel mine meets my requirements for modularity in the hands of the 'backyard mechanic'...or local mechanic. The aircraft engines, while multiple sections, weren't modular.

Chris

Thank you Chris, as I said there was a reason for 'odd' and I'd forgotten it - nicely researched and reminded.

Don't give me "defense of" your design - what's interesting is that you "independently invented it" - somewhat above the level of the original dude.

Well done!

But as you may gather from the above, I think the Mazda version of the Wankel kills petrol piston engines.

I'm sure I will get a lot of negative on this, but having worked on both sorts, raced both sorts, I don't quite know why they aren't everywhere.

'I don't quite know why they aren't everywhere.'

I do.

I thought the reason for less than universal appeal [of rotaries], was the relativly high fuel consumption?

My understanding is the rate of consumption is due to the less than ideal combustion chamber shape.

I suppose you could round off the corners of the rotor, but then you get into a situation similar to honda's oval piston GP bike engine of the 80's. the machining gets complex & the seals [rings] then become less than ideal.

what is the lifespan for a modern version of a rotary?

the air quality regulators get all snippy when the consumption of lubricant increases too much

Well yeah the fuel consumption is high - cause the HP is high - that mass flow thing.

To a certain extent there is a lot of bad press but they never quite get to HP comparison or better still torque characteristics.

Also the "performance" buyer and marketing is addicted to way bigger engines than needed and it's quite hard not to let them out - lead foot wise.

For instance the 4 cyl 1300 Mazda sedan go's ok on about 60 hp. The 13b option in the same package is around 160 hp. Kinda disproportionate

They're hoon magnets, an hoons fit chrome bits, flog the shite and not do service.

But it meant a good supply of "wrecked engines" - 2 hours and a set of seals later, you could take racing.

I actually worked it all out once, that if took the 4.2L 6 out of the 4WD and put in a 13B it would weigh 2-300 kg less, have more torque, pull harder and use 2/3rds the fuel.

But going LPG was cheaper (then they upped the tax - an.......AHoles)

So in my humble opinion the Knobs got it wrong - marketing wise - by going 'performance cars only' and NSU never got the ignition sorted in their sedan attempts.

And here we are - bad press - but not bad product. Well the engine part - that the cars handle like crap didn't help.

yeah my brother [your dopplinganger] had one, he rigged an alternate [advance] ignition box for one set of plugs so it would start in the cold chicago winters

They wouldn't let em run in the same classes [racing] over here, dooming any chance of acceptance

would a compression [diesel] version be possible?

or what would the maximum [effective] compression be?

John Deere Co tried to get the bugs out of their diesel version, Oh, early eighties, but ran out of money trying. I was then in touch with the guys who were doing it

I had a fair bit riding on it. Oh Well. You lose some......

Stu.

Wankels inherently poor fuel efficiency and high pollutant output.

Hi Garth,

It is a significant problem, specifically with the Wankel anyway. GM was doing a 2 year R&D program on it under license from Wankel about the time of the first 'gas shortage' hit. It has a very large surface to volume ratio and these excessive relatively cool surfaces of the metal that make up the combustion chamber on which the gas tends to condense onto and thus doesn't burn. It also has 'numerous 'corners'' that are out of the bulk of the flow and thus are rendered quite 'stagnant.' These factors both decrease its fuel efficiency and increases pollutants. As it is not a 'pure rotary' motion it has traditionally been limited to ~ 9,000 revs/minute due to mechanical limitations. The shape that the rotor moves in and the accuracy that it is required to have is a machining nightmare, especially in 'local/field' rebuilds.

When Mazda first brought Wankels to north America, for the first couple of years they go about 40,000 miles on them at most before the seals gave out. Lots of them gave out closer to 30,000 miles. After a couple of years the Japanese finally fully resolved the seals problem and they had Wankels with 250,000 miles on them that were still running well and still had decent compression.. Thus the first couple of years they were constantly doing engine rebuilds. After they had got the seals down pat, in one year there were only two Wankel engines in all of Canada that had problems with the compression prematurely. They failed because of faulty seals and the mechanics at the Mazda dealerships pulled the engine and changed them and the customers never even knew about it

RE:

'odd numbers of cylinders so that the cylinders can fire in an 'every second cylinder' style, and keep the cycle running in an endless loop.'

What does this mean Chris? Can you expand on it a bit and explain it ?

my comparison is the bolt pattern for tightening wheel nuts, the way I was taught. You tighten the bolts in a 1,3,5,2,4 pattern, so the torque is applied diametrically instead of circumferentially. (which causes uneven warping of brake rotors etc.)

so as I understand it, the odd number firing pattern makes for a smoother pattern.. but I am learning as I go... It's new to me too.

Chris

Hi Chris,

I certainly understand about the wheel tightening and head torquing sequence.

I would of thought that with all of the pistons on one crank throw that they would all have to fire sequentially as the crank rotated and they reached TDC (Top Dead Center) one after the other: IF it was a 2 stroke. I haven't figured it out exactly but being a 4 stroke there are options available to chose and alternate the Power & Intake / Exhaust and Compression Strokes. That could be arranged differently. I'm wondering about the advantages of this? Perhaps increased torque? The firing pattern always makes a difference to the smoothness and vibrations, including the primary, secondary etc. I have a hunch that this may also be a significant factor in this.

If it was completely sequential, one can imagine the torque 'running around and following the firing order. With the resultant vibration tendencies with it. Likely the most significant factor and the primary reason for doing it would be that in a four stroke if they all fired strictly sequentially on the same single turn of the crankshaft, there would be one series of sequential power strokes followed by 3 non-power strokes which WOULD be very weird and cause very weird and erratic, wild vibrations, not to mention the unevenness of the power pulses. Likewise such a completely sequential firing order with the 'one revs of power, 3 revs of non power,1, 3 etc would require a significantly larger flywheel to equalize and smooth out very noticeable intermittent and irregular 3 non/1 power strokes. It would sure have a very weird sounding exhaust and vibrate like crazy.

Still I'd like to check into it further if you have some info references, links etc on this I'd appreciate them.

Nice piece of conceptual work on the 'stacking' radial configuration.

By the links you supplied, one can definitely see that they certainly got into it and milked it for all it was worth. I can't help but smile and chuckle about them taking it all the way up to 112 or 118 cylinder model or whatever it was. Imagine rebuilding it and having it all assembled and ending up with a seal in one of the middle sections leaking if one couldn't get to it except by dissembling all the ones from the end inwards again to get at it. That's when I would want to go get the design engineer and bring him down to it and point out the leak in the middle and hand him the wrench and say : "Here, you designed it, you fix it!' Me thinks it might make him give pause to it being 'too much of a good thing' the next time around.

Hi Doug,

Kyzine provided the Wiki link which contains the information about firing order.

as for why? I have no further insight.

Here is a video that analyzes engine balance, which is of some pertinence.

Here is a super informative animation of the mazda rotary Wankel engine

Here and here are other videos for radial engine animation, but can't find firing demos.

there are dozens of animations of engines on youtube. (search for "engine animation") and some innovative stuff too. I like this one for sleeve valves.

Also, I received an email from Stueywright about my design.

Chris,

Got a few moments now so: 1. The fins are too big. You'll lose too much heat to the atmosphere. Water cool it. Cooling system is easier managed. Engine temps are now critical. 2. Rotate each bank 15deg if you want to stay with air cooling. Subsequent banks mask each other. Run hot. 3. Beef up the crank to crank joint. Spline? Accuracy? Lots of torque going through this joint(as the actress said to the Bishop). 4 Is it a 'built-up crank? How do you get the big end onto the crank throw? First class drawing. Good effort. Why do you want to produce a piston engine? Radial? Have you seen those darlin' little Capstone Microturbines? They're putting them into plug-in hybrids. Be back soon. Work! Cheers. Stu Stu, I really just want people to start thinking 'modular' for cars, and everything about them, including engines. I did look up the microturbines per your suggestion..very interesting. ] Also from Transcendian: Personally I like aircooled engines. The suggestion as to the offset of the cylinders reminds me of the Rolls Royce Merlin, which I think utilized that arrangement for the banked cylinders. Don't think it really necessary for one bank. For the Jugs on something like a R2800 Pratt and Whitney I'm pretty sure cooling is part a function of the type of metal for the fins, and I'm pretty sure it is also the reason fins at the top of the Jug are bigger at the top, than at the bottom. Been awhile since I messed with these sorts of engines. Trans, I think that there is more heat at the top of the cylinder because of the combustion being there, and therefore more cooling fins required. But definitely different metals conduct heat at different rates. Chris

Hi Chris,

I think I more or less worked through the question and figured out the crux of it as I went, but I'm still interestd in reading and learning more about it.

Thanks to one and all.

The microTurbines sounded neat and I went there, but didn't have much time so didn't find any specifics, diagrams, photos of the actual turbines. I know that they can have tremendous power in a very small package due to their VERY high speeds. I remember seeing one that they guy was holding the turbine including the shafts in the palm of his hand. The program said that it was up around 1,500 ~ 2,000 HP because it ran at 250,000 revs/minute. You would most definitely want to have that little sucker balanced VERY well and pay close attention to the bearings, which were most likely 'air bearings'.

Saw a neat low tech one of a family living in the high foot hills/ low mountains in Asia. They had a very low tech but effective cooking/heat and light source with almost no moving parts and VERY cheap: They had a huge relatively thick and flexible, tough round plastic cover. They had dug a pit very close to the back of their hut for all of their live stock and their own waste matter. ('night soil') They kept the plastic cover over it and sealed by very low tech methods. There was a small, clear plastic tubing about ¼" ~ 3/8" ID that came out of the cover that they ran into their house that hooked up to a single burner with a basic, simple inline stop cock valve ~ 2' from the burner. When they wanted to use it, someone went outside and put a decent sized rock on top of the plastic cover supplying a little bit of pressure. NeatO! Now THAT is 'cookin' with gas!

HI Chris,

A good and clear example of flexibility and modularity and of the possibilities of utilizing one platform for numerous applications and configurations.

My engine design shares some of these traits as well.

Nice work. You're pretty handy and competent the variety of CAD apps that you utilize.

Looking at the links: a 112 cylinder 'stack' of radial configuration. WOW!

Radial designs are cool. a Harley is basically 2 cylinders of a radial, due to the shared crankpin design

here's a 3 cylinder version.

a basic problem with a radial is it's not very compact,

the downward facing cylinders [full radials] prone to oil control problems

Rpm's are limited by pushrod operated valves.

an overhead cam set up is possible, but part count & complexity multiply quickly.

Harley's are great gas powered paint shakers

Here's an alternate opposed piston design I find interesting. I had come to this design [conceptually] independantly before I had internet access, Andy Germany [royal navy] wasn't around to point out this design

there was a 4 stroke version made by a john britten, unfortunately this article seems to focus on his more conventional design.

the engine I'm thinking of had an overhead piston running at 1/2 speed in place of valves, kyzine help me out here once poppet valves are removed from the equation max rpm's & power output can go way up

A half speed piston??? .... are you thinking of the Knight sleeve valve? That got re-birthed at some point... shall seek.

Umm, old Napier - this'll get Ky all excited - go Navy!

Actually I think the Boxer is a fair adaptation of the dynamic balanced principals therein.

Don't see much on the net on this stuff - thought Subaru would be in my face - but no - more looking needed on just about everything.

There was a piston mounted facing down. the crankshaft for this runs at 1/2 the speed of the "main" crankshaft. The upper piston serving the purpose of the valves covering up the ports, having a much shorter stroke than the "main".

I think there was a rotary or sleeve valve on the intake to keep everything [gasses] moving in the right direction.

I remember the talk at the time was he couldn't get approval from the sactioning bodies & thus the v1000

I'm getting nothing but vague maybes - but I'll have an ask around the petrol heads. Prob is there's apparently 2 or 3 million patents for infernal combustion engines - confess I've not read em all.

Another thought is the turbine generator used in commercial aircraft and do electric drive.

Another wild arse idea was to use a radio controlled airplane/helicopter turbine to run a generator for a golf cart sized hybrid. cuts way down on the size for the battery pack & would make a really cool sound

I saw this John Deere 4 banger rigged with 2 turbos in series at a tractor pull. The howl was indescribable. worked great until it the rpm dropped & he stopped almost dead in his tracks

Yeah!

I am a fan of OP.

A hard core of designers now re-opening this design. With modern materials and fuel management, it could be a ripper. Uniflow OP, way to go!!!

Stu

... and it can be modularized!

chris

That's quite the design alright. There are a wide range of them. One group of researchers that were examining these types of designs got to the point that it became apparent that it was more efficient utilizing the piston engine purely as a hot, fast gas producer that was then harnessed with a turbine that became the motive force. Eventually they got rid of all cranks and conrods all together. They had two double ended pistons whose combustion chamber was in the center of one long cylinder with no crank or conrods. The outer ends of the cylinder were sealed and when the engine fired it would compress the gas sealed into the outer ends which would then would be forced to and would 'bounce back' to fire again from the stored energy of the compressed gas forcing the pistons together again. Again, they built this specifically to be a 'power source' for a turbine which was more efficient overall than just sticking to the piston engines alone.

Dougie,

Any of these free piston jiggers ever made? Put into service?

Stu

Hi Stu et al,

They built one as R&D following developments on these types of engines, Including the 'UniFlow': Intake at one end, exhaust at the other end of the Cylinder, which I think everyone will readily see the advantages of.

I don't know if it was ever produced comercially, I came across this along with a lot of other variants years ago when I was doing research on my engine.

I rather doubt it though. A lot easier, simpler, cheaper and more efficient ways to come up with hot gas producer to power a turbine: Fan ==> External Combustion ==> Turbine. No other way to get power out of such a configuration with no crankshaft that I can readily see.

Likewise I think that most here will know about the advantages of External combustion over Internal combustion: A LOT easier to tune it for both maximum efficency a substantually reduced polutants.

It is interesting that John Britten's motorbike in your link is "Frameless" with all components being bolted to the engine.

and the Deltic is fascinating... "I'm getting sleeepy... very sleeepy"...

thanks,

Chris

I had read that article. The number of new parts was very low, as I recall.

Just to add another motor. Diesel, Valve less, and Modular

This motor caught me eye about a year ago. I emailed about 6 months ago to see if I could buy one. The response was it is not in production for public yet. I think their target market is for military (vertical take off drones and portable suitcase generators)

http://www.ecomotors.com/

That must be the one with the half-speed piston for valving. very pretty!

Chris

For thought.

Is it harder to make a diesel motor small because of a higher compression ratio needed (10/1)? Larger flywheel verses more pistons and larger crank counter balance?

The motor with a lot of pistons seem to need less flywheel but have a lot of fiction area.

The radial motor needs less crank counter balance but uses a lot of circumference area (space).

I'm looking for the smallest diesel generator (clean burning) that is available now. Can anybody point me in the right direction?

Most Diesels are a 16:1 compression ratio minimum.

How big of an engine are you looking for?

I hired a guy with a large garden tractor with a roto-tiller on it to completely dig up and shred my lawn to rebuild it. It seems to me it was a 4 cylinder. What was quite amazing about it was that this Japanese engine sounded like an Otto cycle engine without any of the distinctive 'diesel knock' and had absolutely no diesel smell in the exhaust! This was a while ago before we had the 'cleaner diesels' with less sulfur in the fuel as they have had in Europe for quite some time now. Ours still has significantly more than in Europe. I worked in close proximity to it for a few hours and didn't even realize it was a diesel until I was helping him get it all loaded up and back into the trailer and we started talking about it. He said that when his old diesel packed it in he had heard about these and checked into it before he purchased. As he said, with the old one, if he moved his hand through the exhaust stream in the early part of the day it still stunk of diesel when he was home eating supper. His clothes had always stunk of diesel as he did as well.

The difference was really quite profound and amazing.

About ¼ ~ 1/3 of new personal vehicle sales in Europe are now diesels, with good reason. Especially now with the cleaner fuel and advanced technology in them. Significantly higher efficiency, much lower wear rate, especially on the bottom end due to the slower spike in the pressure rise once the fuel has ignited combined with the inherent increased lubricating qualities of the fuel due to the 'heavier' oilier content in diesel fuel that also contributes to the higher power density of the actual fuel itself than the 'lighter and hotter' (a reference to the 'vapor point:' it evaporates faster and more readily at lower temperatures), dryer gasoline that washes the lubricating oil off of surfaces rather than helping to lubricate them as diesel fuel does. They tend to have a flatter torque line that is closer to the power output than most Otto engines do and produce it a lower RPMs which is also a factor in their wear rate and longevity.

Large diesels in commercial tractor trailers and large, long haul buses get 10 million miles out of one block with rebuilds. I've never heard of any Otto engine getting anywhere near that regardless of what rebuilds were done to it. I may be wrong about the mileage on the diesel: it seems to me that they get 10,000,000 miles between rebuilds and get a 100,000,000 miles out of a block. Regardless it is significantly higher than any Otto engine.

more of a slow pitch over the plate

to start some discussion about diesels

Doug, Ten million miles is achieved in IC, spark ignited, engines if they are fuelled by LPG (propane). My experience doesn't run long enough in the other gaseous fuels to say, but I'd think, it would offer the same endurance.

The total lack of particulate and bore washing.

Stu.

Hi Stu et al,

Yep, propane does have its advantages to be sure. As you say it burns significantly cleaner.

They have to modify the valves to prevent them from rotating but I've never found out just exactly why as the rotation helps prevent uneven wear and burning through a spot on the vavles, especially the exhaust valve, that then gets enlarged and leaks as is if some took a cutting torch to it.

I know a guy here that is a bus driver so always has split shifts. They live on an acreage about an hours drive out of the city so he puts on a lot of milage. He has converted all of the vehicles he has used for comuting back and forth to work to propane. The improved efficiency/ lowered fuel costs and decreased maintenance and repair costs end up being enough that it ends up being cost effective in spite of the ~ $1,500 coversion expenses. But when it gets really cold he is up the creak as the propane won't evaporate into its gaseous state.

I know that quite a few cabbies convert to propane as well.

Given how clean they burn and as you say doesn't have the tendency to wash the lubricant off of things like the 'hot/clean' (vapour pressure) gasoline does, it doesn't surprise me that they get significanly longer life out of an Otto engine. I have no idea on the stats on them. I can't see most Otto engines in personal vehicles getting a million miles on it let alone 10 million.

Most fork lifts in machine shops and warehouses use propane as well. Some gaseious and some liquid, because the exhaust isn't anywhere near as noxious as Otto engines using gasoline which is very relevant as they operate most of the time within the shop and for a good protion of the year here as there is no way that they can leave the doors open all of the time.

It depends on the type of service it is used for as well: Highway driving is a LOT easier on a vehicle including the engine than 'stop and go' city driving.

I've rebuilt diesels with ~ 1/4 million miles on them and the bottom end on them looks like an Otto engine with about 10,000 miles on them! Basically almost brand new and just broken in.

As to getting 10 or 100 million miles out of a diesel, I doubt if most personal vehicles with diesels get that sort of longevity out of them. But the big commereical ones in large vehicle do. This is reflected in the difference in there original costs and also that the big rigs are revenue producers so it cost effective. Though the inital/ongoing cash outlay must be quite daunting for an individual trucker, especially ones just starting out.

How many of us can afford to or would spend a million bucks to buy a vehilce because it will last a million miles? How much would it cost to keep it running that long? Plus a lot of people get suckered into the pull of a 'new car'. Personally wtih my skills set most of the vehicles I have bought I've got them for almost nothing and kept them running and used them for decades.

With pollution being such an important issue now, many governments have come to the valid conclusion that one of the fastest ways to reduce auto pollution is to get the old ones off of the road and into newer ones which produce far less polution. In north America 100 personal vehicles of ~ 2005 vintage produce the same amount of pollution as ONE from about 1995!

Hence the 'beater rebates' which in Califonia has been up to $4,000.

Of course if they increase the efficeny by 25%, that is 25% fuel being utilized that causes the pollution the first place. In the US the federal government has brought in compulsary 'fleet' fuel/millage efficienies, which have been marginally effective. Mostly they have just paid the surcharge and passed the cost along to customers which given the prevelance and the populatrity of large, heavy oversized SUVs it's obvious that no one minded it, up until gas took a huge jump in price. Historically one of the most efffective methods has been to make fuel signifcantly more expensive and then people start buying more economical ones which we have seen happen in the last several years in north America. If gas was still less than 20 cents a US gallon (4 liters) like it was when I was a child, we would still all be driving venicles that get less than 10 MPG. I can still remember the 'outrage' when gasoline went to 17 cents an imperial gallon (~ 5 liters)!

Do we really need a vehicle of 2 Tonnes/Tons to haul around usually just one person and a couple of bags of groceries that only weigh ~ 200 pounds ~ 100 Kilos?

The overall improvements in fule milage has been dismall. I don't remember the exact figures, but it is something like only a 2 MPG increase in the last 20 yearrs, which is just pathetic and perhaps even criminal, compared to what is possbile.

The sterling cycle engine which is external combustion, but was way ahead of it's time as the materials and the technology wasn't anywhere near being fiesible when Sterling concieved of it and 'invented' it. As I'v said, the have put quite a number of them into satelites because of there efficency, though obviously the have to provide oxygen for it, unlike nuclear power as teh heat source. Obviously they last a long time as well, which is quite amazing given the internal pressures of the gas utilized in them that they need to have to be effective and efficient: ~ 150 times that of normal atmospheric on our planet.

But they probably have a budget of 10 million bucks for the engine that is warranted given the application, lenght of maintenance free service and duration of operation required of them.

Most personal vehicles engines life expectancy is 2,000 ~ 4,000 hours.

They have to modify the valves to prevent them from rotating

Must be specific to where you are. We've never done it here. 40yrs.

I can't see most Otto engines in personal vehicles getting a million miles on it

We keep our cabs in service longer here, it seems. Many have well exceeded this figure. Eventually let down by the bodywork getting creaky.

Interesting to note that quite a few cities have banned diesels from operating within, due to the particulate emissions. Singapore is one to start your research at. the Diesels are converted to gaseous fuel operation. LNG, CNG.

I've rebuilt diesels with ~ 1/4 million miles on them and the bottom end on them

Us too. Have you ever wondered the 'real' reason for this?

Do we really need a vehicle of 2 Tonnes/Tons to haul around usually just one person and a couple of bags of groceries that only weigh ~ 200 pounds ~ 100 Kilos?

Us too. Have you ever wondered the 'real' reason for this?

Frankly, for my 60yrs involvement in cars, I've never figured this.

I can only thank the happy coincidence that we we're a British colony. 'Yank Tanks' were treated with disdain and despised by most. I did, one time, have a '62 Pontiac Laurentian and then a '62 Chev. BelAir. Thought they were the greatest waste of resource ever. And, NO BRAKES!!! Pissy little drums. Didn't have 'em for long.

Folks had a 'hot air' (sterling cycle) engine to drive the dairy machinery from mid '40's' to late 70's. I still see that it would be relevant today, aven tho' it was a big old girl. All cast iron, Huge flywheel. Spirit blowtorch or wood fire heated. A construction the size of a Mini, and 4 HP.And SILENT. No maintenace to speak of, and reliable as the sun.

Stu.

Yep Stuey - it's the bulk/weight per HP that's against Sterling's, in the vehicle context. But terrific for low grade heat conversion. Have you seen the Sterling powered fan? 15 and in post #16 Jost Hot Air Fan

As for the 'sweeping generalizations' emanating from ∞ hat, there are diesels and diesels. Also petrol engines that poorly convert to LPG. Some fully stressed - some lightly stressed. Some good for 50 hrs - some for 50,000 hrs. Pointless benchmarks that would put a marine diesel in an FI

Jost Hot Air Fan.

You got me. Not seen one of those before. Neat machine. I'd have the heat source outside the room-longer shaft -- we need cooling here. This would be rather more effective as a heater. No?

I'm not a pusher for sterling. Just able to recognise that it has it's applications.

Stationary dairy pump prime mover doesn't indicate 'small and intricate'.

Being a qualified Engine Designer, I know enough to not poo-hoo others efforts. But I do know that the Physics rule book hasn't been re-written.

Most people working on 'new design engines' refuse to acknowledge that physics rule book, or in fact know anything about the actual physics/mechanics/ metallurgy or what they're trying to do.

Amazes me.

I've been asked hundreds of times to 'look at' a new design, and upon a constructive crit., have seen the projects continue 'till the Inventor is broke.

Re the latest fashion: OPOC.

You have some experience in engines. And a good deal of common sense.

The claim is for wildly increased horsepower and fuel economy. Figures quoted. Mostly BS. They're quoting the theoretical figures. Practise is always something different. The unit on show is basically a four cylinder engine. What's the critical component here? Pistons In a highly stressed four cylinder Diesel it can be expected that the pressures will peak 3300psi. Given the area and the lever Torque can be calculated. But, run one near these pressures and piston failure is imminent. Even with the world's best Mahle pistons. Then someone comes along and wants me to believe that they can get 40% more????? We're all still throwing billions of $'s at trying to regulate the combustion so as not to have this happen. There is so much compounding in this realm, no-one has all the answers.

This post IS designed to encourage the reader to further independant research, as are all of mine. I'm not here to lecture.

Hopefully to point out that there is a commonsense simplicity which is ruefully omitted in this realm.

Stu

I was just pointing out some things I've bumped into

at the end of endless summer there eh?

what about natural gas as delivered for home heating & cooking? It would be nice to have the full strength shiest as it comes out of the ground. That would require a whole new infrastructure, which is about as likely as things going all sunshine & roses in Haiti

anything cheaper [for automotive use] than what amounts to scuba tanks & expensive compressors?

what about natural gas as delivered for home heating & cooking? It would be nice to have the full strength shiest as it comes out of the ground

The mixture and pressure that it usually comes out of the ground at isn't realistic for consumer use. Tends to be a lot of nasty things like 'sour gas' (hydrogen sulfide) that is very deadly mixed in with it. Lots of other types of hydrocarbons as well that aren't necessary for heating purposes and are useful for other things, not to mention the reduces pollutants from cracking it down.

As to the pressure: for one thing it needs to be regulated so that it IS at a consistent, safe pressure. Otherwise in most cases it would be overkill, probably literally in quiet a few instances. Several decades ago a natural gas main pressure regulator for an entire US subdivision failed and went from a few ounces per square inch to ~ 100 psi into peoples household gas appliances, water heaters, furnaces etc. This was in the days before spark ignition on most gas appliances so almost all of them had pilot lights: which immediately became 25' ~ 50' flame throwers, not to mention the main burners that were active or the gas valves that got blown up or right past by the pressure. The whole subdivision went up in a very short period of time like it had been saturated with incendiary bombs all at once.

Here virtually all permanent buildings within any decent sized settlement have natural gas piped into them. A LOT cheaper than electricity, which in the city I live in is primarily produced from burning coal )< 8(

What are the energy sources that are used for cooking, heating water, space heating and cooling etc where you live Garth? Stu?

SNAFU comes to mind.

Everyone else uses fail-safe first and second stage regulators.

2" of water is the standard appliance pressure, by the way.

For the other "Don't Knows"; gas scrubbing 101.

Kyzine:

2" of water is the standard appliance pressure, by the way.

So the pertinent fact here is that the normal operating pressure for natural gas appliances is 2" of water as opposed to a couple of ounces and thus the whole subdivision wouldn't have been incinerated because of this minor difference when it went to ~ 100 psi ?

<Um- Kyzine - no "L" - an improvement >

Ok Doug;

What you got here is "as reported";

Facts that conflict;

Single stage (house) regulators cope with ~200 psi - they are the same 'safety factor' as LPG welding cutting regs. Same stuff - same rules.

What has happened is; No 'fuses'. No head relief on sub networks = shonky breakdown from the HP main, which typically is 900 to 2000 psi. Maybe 3600 from a hp store.

The 'limitation' here is reporters get it wrong - because they don't understand - well, anything.

To figure out why it went wrong - you have to know enough to see what they got wrong

So to short cut that; It's not the Gas that's "Super Dangerous" - it's the technically inept idiot that didn't understand it.

Not doubting it happened - or can happen (with the same idiot) but it comes under "Blind Stupidity" not "LPG is inexplicably dangerous"

It is totally "explicable" for/to those with basic knowledge.

Some people should not have sharp things is not an argument about sharp things, it's an argument about people.

So to be "On Topic", the tenuous link is people drive cars.

But somehow you have felt this is "On" so I leave so.

I should have formulated a more detailed observation.

During the scrubbing process various inert gases are added to make a safer product for harriet homemaker. These additives reduce the btu's per liter at all pressures...

a higher potentcy methane based fuel, that didn't have to be processed as much, for use as a motor fuel, is what I'm advocating.

In the US propane forklifts can only be used sparingly, in closed quarters, due to safety concerns over the fumes. While a properly tuned propane powered forklift, doesn't emit too many nasties, there are still a certain percentage of unburned fuel & CO. Electrics are the preferred choice...

Hi Garth,

Thanks for the further info. I never liked the fume from the propane either. Being a machine shop and thus the considerable weight that the forklifts are often moving almost constantly in a busy shop rules out electrics. I've never come across an electric that was anywhere near big enough to handle machine shop applications anyway

FYI: there was MANY a time I wished I was working in a Balsa wood factory and not steel (< 8)

But the propane fume are far more preferable than gas or diesel. I worked in one shop that had a diesel for inside the shop and it was horrible. I didn't stay there long just for that reason,

Regards,

Doug

I was using a electric forklift similar to this in 1980 in a factory that made large commercial washing machines

http://www.hyster.com/Europe/en-GB/Products/ElectricForkliftTrucks/4WheelElectric40-55TCushionTyre.htmx

Hi Garth,

Nice. Definitely some serious capacity in those.

I don't work in nor own a machine shop, but tis a good thing that they are around and available.

Makes me wonder why more shops don't use them. Probably convenience: most shops only have one forklift and can't afford to have the battery die in the middle of the day. They always have at least one full fuel cylinder around that make it considerably faster to 'charge up the fuel' for them.

Regards,

Doug

Most people working on 'new design engines' refuse to acknowledge that physics rule book, or in fact know anything about the actual physics/mechanics/ metallurgy or what they're trying to do.

Came across a guy selling interlocking 'aluminum roofing 'shingles'' in a kiosk in a mall once. I asked him about the effects of contraction & expansion due to temperature variations on them, which is significant here. His response "There is NO expansion and contraction of them." I asked him is they had successfully rewritten the laws of (Quantum) physics.

Its definitely a field that is well picked over to be sure. Hard to come up with anything that is 'really new' including the OPOC. I didn't have much time to go over it, but looks like a 2 stroke with good packaging. The horizontally opposed pistons is a nice configuration and makes for a fairly compact package, except in the dimension of the cylinders. The modularity is a nice touch and could be a significant benefit in some applications. I didn't see any ports in the cylinder walls though. From there 'exploded view' parts illustrations, I was wondering if they were using a very large HD reed valve at the top of the cylinder, which seems highly unlikely and unworkable.

....continue 'till the Inventor is broke

Seen it a number of times myself, sad but true. Saw one rotary working prototype in a guys home garage that reminded me a bit of your friend's. This guy was quite sure and adamant that they WOULD have to rewrite the laws of physics because of it! I haven't seen nor heard anythign more about it includign rewriting the phsyics books because of it.

Responce to:

"I didn't see any ports in the cylinder walls though. From there 'exploded view' parts illustrations, I was wondering if they were using a very large HD reed valve at the top of the cylinder, which seems highly unlikely and unworkable."

This exploded view leaves use to do a lot of guess work about the manifolds. The OPOC site last year posted an explanation about the port location was very important. If I remember correctly, the red piston port open slightly before the blue piston port. (Red exhaust, Blue intake) There is some exhaust elements remaining in cylinder for secondary burning. The manifolds are common to both cylinders and are only open to one side at a time. The piston location it self is the valve (closed when pistons block port). The electric turbo helps a lot.

The older OPOC site had links to test run demos and component views of palm held proto-type.

I'll check-in again in a week.

I looked at the MicroMotors web site I believe it is that uses the same basic OPOC configuration. But there being 4 conrods and pistons in a 2 cylinder (2 stroke?) I didn't spend a lot of time there. They have short pistons at the top of the cylinder over and over the normal piston and crank throw that is used to open and close some ports in the top of the cylinders as well. It would appear that it is is a uniflow in this configuration.

Somewhat considerable increase in complexity but the advantages would be tangible.

Re MicroMotors:

This exploded view leaves use to do a lot of guess work about the manifolds. The OPOC site last year posted an explanation about the port location was very important. If I remember correctly, the red piston port open slightly before the blue piston port. (Red exhaust, Blue intake) There is some exhaust elements remaining in cylinder for secondary burning. The manifolds are common to both cylinders and are only open to one side at a time. The piston location it self is the valve (closed when pistons block port). The electric turbo helps a lot.

This is all standard, traditional technology.

Do they have any significant variations or mechanisms or just that they have done a very nice design and construction and maximizing the engines output by only operating it within a very narrow rev / power/torque bandwidth that ported 2 strokes are VERY sensitive to.

This is also a VERY good example of the benefits of IC engines as applied to Hybrid Autos:

Like most industrial applications, these engines very likely only run at one very narrow speed and power/torque range.

Thus there considerable advantages in hybrids operating in this same mode that is very beneficial in spite of the significant additional expensive complexity.

Now that you've hyjacked the thread what are you going to do with it?

You have some agenda

what is it?

we get it you can talk over everyone

deride every suggestion made by anyone until it sounds like unworkable shiest

so what's you plan?

oh wait you can't talk about your plan, it's revolutionary, proprietary, blah, blah, blah

But you can't tell us it's your life's work, patents not complete, funding in process...

sounds like all the HHO guys, that invade from time to time.

Jost's were mostly used in days of Raj, by folks summering in the mountains. It's a toss up if it's the first 'fan heater' or not, its not much of a flame (think big hurricane lamp) but still 'open plan' ventilation is an idea. "Shafting in" - good idea - might have to dig him up and ask "What were you thinking Mr Jost?"

On OPOC: I think the 'main advantage' is the increased speed of compression - CI is very dependent 'cranking speed' to get squish fast enough to have the air hot enough to ignite the fuel. I'm sure if you've had a few lazy batteries, you know pretty instantly if the thing will reach the magic speed, first touch of the button.

So extrapolating on 'starting' at lower crank revs, you get a slower, higher & better spread torque.

But, I think it looses in extra bits (+ 2 long con-rods, extra piston friction - verses valve train?)

Next is porting losses and 'fixed' valve timing. Means you can't have cam advance at higher rpm, can't alter valve overlap, whole range of cant's now entering engine management.

Next is; limited and dubious injector pattern - so flame front - so 'clean' and 'power'.

So in theory at some point, combustion is 'perfect' .......in practice - it's 'for ships'.

But given the piston size required you'd want the bores vertical.

And here is a link to read and enjoy - then click on the engine pic at the bottom - then it's pics at its bottom.

The World's largest Container Ship launched

Kyz

The main objective of Britten's version of the opposed piston concept, was to raise the max rpm's

Rpm's are the enemy of spring return poppet valves, float & bent valves being the result.

like a ducati with it's positive actuation more Rmp=more HP/liter

the britten prototype was a shared crank pin V-twin to utilize the larger capacity allowed under the rules.

the overhead crank was geardriven, I believe.

Part count about the same as a traditional arrangement

weight of the entire powerplant very similar.

I agree, the OPOC thing introduced itself on the premise of piston critical speed - so rpm - but I think lost its way. Never going to be an issue/advantage with less volatile fuel - baring a super under square design. But that's their embodiment - not the "whole principal and all others in class".

I.e. I'm sure someone can do a better approach than the VW start point. I did find it fascinating.

I remain unconvinced with all that stuff waving about, that very high rpm is 'better' than the over-square, light as buggery approach in F1 and for that matter 2 stokes.

Piston velocity is after all a function of crank throw.

Right click, properties

Stu.....

'I'm not a pusher for sterling. Just able to recognise that it has it's applications'

Thinking about them using Sterlings for satellites, seems likely that they utilized some sort of radiation heat source for them. Doesn't seem that they could or would be able to carry enough of both fuel and oxygen to last very long otherwise.

This goes back quite aways: before either solar cells or the space shuttle, so not a lot of options.

Regards,

Doug

Name calling dismissive put downs, and a VERY sweeping, all encompassing generalization to boot! Very mature Lyzine. Says a lot more about you than it does me. So by all means: please continue.

Don't know of any Ottos on public roads converted to LPG, just gaseous. They out last there petrol powered counterparts significantly with lower operating costs as well.

Some forklifts use liquid, other gaseous. Which ever it is, definitely preferable to gasoline or diesel in an enclosed space where one is working 40+ hours a week.

True - sounds like you have now conveniently forgotten you "drew first blood" with "Lyzine" and obviously choose to persist.

Now; to assist you toward ceasing writing, as if what you "Don't Know", is some sort of authoritative benchmark;

Go find out how automotive [universally] liquid feed LPG systems work.

Then; you can look up 'direct injection of LPG' current developments in both SI and CI.

That you cannot see the OPOC ports, or understand the aspiration, is probably due to lack of 2-stroke, knowledge/experience. Go learn it.

A further tip on dropping terms you don't understand: "Otto cycle" means 4 stroke cycle - it does not predicate "spark ignition" (except among the hopelessly uninformed with zero "Otto cycle" CI experience)

Now this is not an attack on you - just an attempt to drag you out of total ignorance and save you the embarrassment of looking more of a fool with every new more verbose and increasingly braggart diatribe you post "in defense" of your latest blunder.

Don't know of any Ottos on public roads converted to LPG, just gaseous.

Doug,

LPG, universally and worldwide, means Liquified Petroleum Gas, and is propane.

Various climes dictate that, specific to it's intended use, that a modicum of butane may be added. To both the mixes is added Ethyl Mercaptan, the odour, as neither of these gases are naturally odorous. Two types of cylinder is offered. For domestic use, 'gas' withdrawal, and for automotive use, always 'liquid' withdrawal.

In an earlier post you mentioned the problem of non-withdrawal in cold weather. Simply warm the cylinder a little. Where the ambient temp is likely to get below 5degC for significant periods, the gas will contain NO butane. You could carry liquid butane around in an open bucket on a 'cold' day. Won't boil off.

All forklifts, indeed all spark IC powered equipment which works indoors for any period of it's usage is legislated to be fuelled by LPG. Depending on the ventilation of the work area diesel is sometimes allowed. The combustion byproducts of IC + LPG are CO2 and water vapour, and of course heat. That's it.

Stu

OH! I forgot to mention, the internal pressure in a typical LPG cylinder, filled with liquid, is 150psi.

Stu

Stu:

In an earlier post you mentioned the problem of non-withdrawal in cold weather. Simply warm the cylinder a little. Where the ambient temp is likely to get below 5degC

Here it stays below -5C for 4 or 5 months Stu.

Thus 'warming up the cylinder' is in no way practical. every time one needs it. Even if one does so to get it started, it's going to drop down below ambient temperature both from environment and get even further cooled by evaporation (in the case of gaseous applications)

Even without Butane in it Stu, it gets cold enough here that the propane sans butane could likewise 'be carried around in a bucket'.

I know that when it gets really cold, down as far as -50 C and even more on occasions, he has to use a different vehicle than the LPG one as it won't start or run.

Regards,

Doug

Wow!

That's cold!

Well, if I was presented with that problem I'd fashion a 'proximity' heat exchanger to warm the tank from exhaust emissions/ or pipe proximity. I can think of about ten ways to do it of the top of my head. Start on gas(petrol) and warm the tank for a while and switch to LPG. Need to have an exhaust diverter valve to direct the heat away from the tank in the warmer months. You're handy. I'm sure you can do it. Stu.

Well, if I was presented with that problem I'd fashion a 'proximity' heat exchanger to warm the tank from exhaust emissions/ or pipe proximity. I can think of about ten ways to do it of the top of my head. Start on gas(petrol) and warm the tank for a while and switch to LPG. Need to have an exhaust diverter valve to direct the heat away from the tank in the warmer months. You're handy. I'm sure you can do it. Stu.

Thanks for the suggestions but currently I don't even own a vehicle.

I don't see most of them being practical or feasible though. Even with the considerable heat from the exhaust, given the size of the propane tanks, Steels thermal density. The rate at which the heat can and would be carried away due to the speed of the vehicle (wind chill?) Some mount the propane tank at the front of the box in the truck, other's underneath. They both have there draw backs as for trying to coble up and utilize the waste heat in the.

Most couldn't or wouldn't go to such efforts to facilitate these.

The cabies are happy to stay home when it's that cold, and my friend uses is other vehicles. Global warming &/or normal variations in weather patterns have made our winters quiet a bit milder and generally shorter. It's not very often that we get it that cold for very long anymore. Which suits me just fine!

When I was a kid, there were times when we went 40 days with it below -40. The local newspaper printed a 'certificate' saying that 'I survived 40 days of 40 below weather' Not a good time to be a homeless person. I can't imagine it here even with our milder winters now.

Regards,

Doug

Well! There you go!

I would do something about the problem, not just complain.

Just because you don't see how it can be practical, won't stop me from doing it.

The thing's a piece of machinery. Do you want it working for you, or against you?

I guess that's where we differ. I'd change it asap. (There's no such thing a s drawback. Just a temporary impediment.)

And it would have 'style'.

Cheers,

Stu

Hi Stu,

Not complaining, just the realities of our winter climate and the limitations of and difficulties in utilizing LPG when it's really cold.

If I had a vehicle that I wanted to convert to LPG, then it perhaps it would be different story. But as I don't.....

The acquaintance that put on lots miles commuting, and finds LPG for his truck and the odd occasion when he has to take his petrol vehicle still figures that overall he comes out way ahead with primarily utilizing LPG and is quite satisfied with the arrangement he has.

Lost of things are possible if one is determined.

As you noted, how many engine inventors have been blinded to the limitations of there design but have carried on trying to overcome problems that are inherent in the design that make it either impossible, or unrealistic for an individual to have the considerable resources that might be required to overcome them. Even if they are successful, if they just have a different configuration of an IC engine with it's inherent problems, and as you say is at least 30 years out of date, if not 50.

It would be best if we had the level of technology that F1 has in our personal vehicles. How many of us have millions to own and operate one?

Like you said, the laws of physics aren't going to change for our convenience.

Like yourself, I have done numerous things that i have either created a work around for a problem, overcome &/or fixed problems with a manufacturers designs that were problematic. I've spent most of my life repairing, fixing things, improving on them and creating solutions to problems when none were available.

LPG isn't a problem for me in real cold weather and I have no interest, nor the resources to create a solution for this problem. As you say, like gasoline here they modify the blend to suit the seasonal variations to make them the best they can and suitable for the temperatures.

Regards,

Doug

It would be best if we had the level of technology that F1 has in our personal vehicles.

We Do!

If you really look into them, modern engines have all of the sneaky bits.

No they don't perform like an F1, nor would we want them to. Gulping fuel usage, inconvenience, high maintenance, not to mention noisy.

But if you study really carefully you'll see the stuff. Mass reduction, combustion controll, emissions reduction, performance. It's all very sneaky stuff.

cheers,

Stu

As I said, I have no idea on preventing the valves from rotating, seems counter intuitive to me. How would one achieve it?

Judging by your picture I'd say it is much warmer there now than it is here. Where you living now Stu if you don't mind me asking ?

I wonder how the newer, 'clean' diesels & fuel stack up?

I've rebuilt diesels with ~ 1/4 million miles on them and the bottom end on them

I've got some ideas, but you're the engine designer. Please enlighten me.

Don't see to many Sterlings in use to be sure.

Judging by your picture I'd say it is much warmer there now than it is here. Where you living now Stu if you don't mind me asking ?

I live just where it says on my signature. Au = Australia. Woodridge is about a third of the way from Brisbane to the Gold Coast. Yes, it is warm. Right now @1931hrs it is 30degC. There is a breeze. We don't have the refrigerated air turned on.

Stu.

Hi Stuey,

I've rebuilt diesels with ~ 1/4 million miles on them and the bottom end on them that look like a petrol engine with 10,000 miles on them. In other words, the bottom end is really only just 'broken' in at 250,000 miles which is really quite phenomenal.

Us too. Have you ever wondered the 'real' reason for this?

As far as I know the primary reason for it is that Diesels pressure rise when the fuel ignites is not as sudden a pressure increase in the cylinder that the petrol engine has.

With a significantly 'heavier' oily content, I would think that that all other things being equal, that the petrol would burn faster than the diesel, which would also result in the Diesel burning longer so would have a more effective and longer drawn out burning thus the entire 'pressure curve being 'gentler' and longer drawn out burning period overall' than gas which should also add to giving it more torque.

I would think that another factor would be that Diesels don't generally rev as high as petrol engines do

All of these added subtle differences together would make it easier on the Diesels and not cause as much wear on the bottom end

The overall improvements in fule milage has been dismall. I don't remember the exact figures, but it is something like only a 2 MPG increase in the last 20 yearrs, which is just pathetic and perhaps even criminal, compared to what is possbile.

It's much worse than that, at least in the US. The fleet average fuel economy peaked in 1985 (at about 25 mpg), and has gone downhill ever since (to just over 20 mpg). Engine fuel efficiency (i.e., BSFC) however, has improved significantly since 1985, and power-per-liter of displacement has made stunning gains. But in 1982, the 68 hp Ford Escort was the best seller in the US. Today, the Ford F150 pickup is the best seller (and zillions of even heavier truck-based SUVs have sold incredibly well) and most of these are used as passenger vehicles, and most carry only (on average) 1.1 people.

All along, there have been very-efficient-to-highly vehicles available. People in the US do not buy them in large numbers for the same reason that new houses are much larger than older homes -- we give only lip service to saving energy or resources, and are happy to spend money as if it grows on trees. If we cared about such things, the original Honda Insight (which virtually every household should have had at least one of, for commuting and around town) would have sold like hotcakes. They are spectacular for their absence on American roads. Seeing one is like seeing a Whooping Crane.

McDonald's says "You deserve a break today." I say bunk. Americans already have have a sense of entitlement, and hardly need further encouragment: if each of us can afford (by old bank standards) to buy 2 or 3 huge cars, a huge house, a place at the beach, and a huge boat, we should, we say. Just before the current depression, buyer behavior showed that we could care less about environmental issues and we were happy to elect a president whose policies favored buying huge vehicles and favored tax cuts for the rich to encourage even more conspicuous consumption, despite the fact that our energy consumption, per capita, is already double that of any other developed country (except yours.)

Thanks for the detail "Most Diesels are a 16:1 compression ratio minimum". I'm trying to understand diesel better. My guess was based on Gasoline needs higher octane at around 10:1 compression ratio to reduce pre ignition. Higher octane reduces the ability to pre ignite. Does diesel have a high octane rating? Does the diesel generate higher torque because of the high compression ratio?

I'm contemplating building a electric/fuel hybrid.

I would like to use diesel fuel because the tank is not regulated for vapor containment like Gasoline tanks (makes for flexible tank planning). Also diesel does not turn to varnish over time like gasoline (My goal is to leave the fuel in the tank as long as possible).

I'm not sure what size of diesel motor I need, so here are my criteria.

1) Available now.

2) Motor weight light as possible because of minimal use. (Motor not to be used except for cross country or hill climbing) Primary Vehicle use is local transportation.

3) Diesel motor to become primary power for vehicle at speeds 45-70 Mile per Hour.

4) Motor to run open throttle efficiency with spill over power to generate electricity.

5) Vehicle weight to be about 2000 pounds gross.

Is it possible or is there any reason to use diesel with lower compression ratios and igniting with spark? I like that diesel has more power energy per weight of fuel, self lubricates, and burns cooler. Does a clean burning diesel motor put exhaust higher up into the atmosphere similar to gasoline with longer term effects?

More question about diesel fuel. What can I do with it?

I see the benefits of large diesel motors but I would like a small diesel motor less than 100 lbs in weight. Is their a limit on how small of a motor can use fuel injection?

Is the air/fuel ratio of diesel motors about the same air/fuel ratio of gasoline motors? Are injectors about the same size?

To broaden my options, will diesel fuel work in a gasoline engine?

http://en.wikipedia.org/wiki/Diesel_engine

here's a company that makes a small diesel

http://www.hdtusa.com/

100 pounds is pretty light for a diesel

here's a generator pretty close to what you're talking about

I used one [75kw] for a year, I pull started it even a few times

when you talk about diesel fuel the rating is cetane