Author Topic: Theory/Principles?  (Read 4838 times)

deepstate

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Theory/Principles?
« on: June 26, 2018, 04:50:40 AM »
Hi,

What kind of diesel engine is the Lister? Is it like a 2 cycle Detroit Diesel without an injection pump? Why are people talking about spark plugs? Is there an introduction to the theory behind these machines? What  makes them run for so long and why are they special?

Also, is it confirmed there are no drawings online? I am unable to find any technical drawings or diagrams.  I can pause youtube videos and make out some of the parts, but I don't know what they do.  Maybe drawings and diagrams were online at one point, but no longer available? I've tried several hours on google.  If you have a link, I am interested.

Thanks

deepstate

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Re: Theory/Principles?
« Reply #1 on: June 26, 2018, 06:11:01 AM »
no, I am a small farmer and I just started growing hemp. I would like to run a generator on hemp oil for 4-8 hours a day to run electric pumps from a pond and irrigation system.  But I want to be able to see how difficult it would be to rebuilt it.  I found a rusted core, but the guy who has it probably won't part with it.  He might let me borrow it, if I am unable to find drawings, I will do that and see if I can trace it into FreeCAD. 


mike90045

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Re: Theory/Principles?
« Reply #2 on: June 26, 2018, 08:01:32 AM »
The 6hp, 1 cyl  (6/1) is a 4 stroke, with mechanical injection.  Most heads inject into a pre-combust chamber, most have a option of a slug that can screw into the chamber to increase the compression ratio for easier cold starting.

Restoring, it's mostly parts - where are you and what can you get ?

mikenash

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Re: Theory/Principles?
« Reply #3 on: June 26, 2018, 08:35:25 AM »

deepstate

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Re: Theory/Principles?
« Reply #4 on: June 26, 2018, 08:45:07 AM »
thanks, I was hoping to see a diagram.  Is a mechanical injector the same as a mechanical pump? Does the fuel get pressurized in the injector itself, is that what makes it so special, verse outside of the injector in an injector pump? (a separate device that then connects to the injector on say a old tractor)

Is the mechanical injector superior to a pump + injector?

I guess what I am trying to get at is why these machines last so long vs something like a Fordson Major SIMMs inline pump or something with a rotary pump, like John Deere/Furgenson 35/Case 188D with the stynadyne/roosa master rotary design

Obviously the less parts, the less things can break down

What I don't want is some weird one off injector that I have to send to a lab halfway around the world to get some .00035 part made, and wait 3 months for it to come back

A diagram or drawing would really help me

ajaffa1

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Re: Theory/Principles?
« Reply #5 on: June 26, 2018, 09:38:06 AM »
Hi Deepstate and welcome. Lister engines come in all shapes and sizes, they also designed and built engines to run on petrol, kero and diesel. The single/twin cylinder Cs engines are remarkable because of their simplicity, longevity and ability to be converted to run on pretty much any fuel you have at hand, including vegetable oil.

The Injector pump is mechanical driven directly off the cam shaft, the fuel is then piped to an injector in the cylinder head where it is sprayed into the cylinder and mixed with air. The compression in the cylinder is sufficient to cause the fuel air mixture to explode.

The beauty of these old diesel engines is their simplicity, reliability and ease of servicing. Basically any reasonably competent mechanic can service one of these with little more than a bag of spanners. Thanks to enthusiasts and India making clones, parts are readily available

If you wish to learn more have a look on the WOK at the top of the home page. 38ac has dismantled and rebuilt a fair few and has posted a lot of photographs and useful information.

Have fun,

Bob

mikenash

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Re: Theory/Principles?
« Reply #6 on: June 26, 2018, 09:49:38 AM »
Just google "Indian Listeroid diesel engines" and spend a couple hours looking at all the advertising stuff from the many Indian makers of these modern "copies" of the original Listers

Then go to:

https://www.oldtimerengines.com.au/lister-engine-parts/lister-cs/

and :

http://www.centralmainediesel.com/order/lister-parts.asp

and you will see what the component parts of these very simple engines are, and that every part you could ever need is available, cheap, off-the-shelf, and of good-enough quality

A quick description:

What you are looking at is a Lister CS (cold start) single-cylinder, water-cooled, indirect-injection diesel.  It has a cam-driven, piston-operated, mechanical injector pump and conventional injector unit.  There are no electrics or electronics.  Although the design is very sophisticated it is also very simple and unbelievably robust.  They are designed to be able to be properly maintained by the "village blacksmith".  Lubrication is by splash and simple, no-pressure oil-pump.  Cooling is by thermosiphon

Since they are of very very heavy and very good quality cast-iron construction, and since they run at 600 RPM, they are very long-lived

People like me and others here like them because they were genuinely made to be endlessly re-buildable, but are quite capable of giving many thousands of hours of reliable service between rebuilds

There are no detail drawings extant that I am aware of

But if you are willing to help yourself by looking at the sites I have suggested and doing some reading, you will easily gain a good understanding of what they are and what they do

38ac

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Re: Theory/Principles?
« Reply #7 on: June 26, 2018, 01:05:06 PM »
Hi and welcome.  I have little to add to what has been said. Lister built both diesel and spark ignition engines. There are seperate forums here for that but subject matter is pretty much intermingled.  If you look in the WOK section I wrote up a ramble on how to build up a clone, most of which would apply to a Lister CS. Plenty of pictures to help you sort out what's inside.  Anyone with basic mechanical abilities a d a handfull of tools can rebuild one with the help available on this site.
Collector and horder of about anything diesel

ajaffa1

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Re: Theory/Principles?
« Reply #8 on: June 26, 2018, 01:18:15 PM »
Hi and welcome.  I have little to add to what has been said. Lister built both diesel and spark ignition engines. There are seperate forums here for that but subject matter is pretty much intermingled.  If you look in the WOK section I wrote up a ramble on how to build up a clone, most of which would apply to a Lister CS. Plenty of pictures to help you sort out what's inside.  Anyone with basic mechanical abilities a d a handfull of tools can rebuild one with the help available on this site.

Hi 38ac, if that`s a ramble I can`t wait to see what you have to offer when you put your mind to it! :laugh:

I ramble, Glort rants, what a great forum.

Bob

AdeV

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Re: Theory/Principles?
« Reply #9 on: June 27, 2018, 08:17:23 PM »
Is a mechanical injector the same as a mechanical pump?

No. A mechanical injector requires a very high pressure pulse of fuel, the extreme high pressure overcomes the spring in the injector allowing it to open a tiny fraction. That tiny opening causes the fuel to spray out in a highly atomized (little tiny tiny droplets) mist, which is the best way to mix it thoroughly with the air in the cylinder that then allows the explosion (actually a controlled, but very very fast, burn), which is how the magic happens.

A mechanical injector pump is just the means of producing those extreme pressure pulses. They rely on the fact that liquids are, to all intents and purposes, incompressible (not incomprehensible...) a bit like a hydraulic system - only many thousands of PSI. The Lister's mechanical fuel pump is an extremely simple cam-driven affair; a cam on the camshaft pushes a tappet up which squishes the liquid in the fuel line. Since the fuel can't compress, it's forced out of the injector (see above).

Is the mechanical injector superior to a pump + injector?

The mechanical injector requires a mechanical pump to work. The injector on its own does nothing...

More recently, you may have heard of "common rail" diesel engines - very popular in cars. These have a single pressurised fuel line going to all of the injectors; it's at a lower pressure than a mechanical injector pump will deliver, but still many hundreds of PSI. The injectors are then controlled electronically. This has the advantage of only requiring a relatively simple pressure pump (which can be electrically driven), one fuel line, and the injection timing can be changed "on the fly" by the engine's ECU. As Lister CS engines pre-date computerisation by some years, they use the old-style mechanical injection system. Timing it can be a bit of a chore...

I guess what I am trying to get at is why these machines last so long vs something like a Fordson Major SIMMs inline pump or something with a rotary pump, like John Deere/Furgenson 35/Case 188D with the stynadyne/roosa master rotary design

Simplicity, primarily. There's only one cylinder to power, so there's no internal drivetrain, and virtually no moving parts. Plus, coming from a time when longevity and reliability were design goals rather than dirty words (and "built in obsolescence" hadn't been invented yet), they were literally massively over-engineered for the job at hand. Also, most Lister CS engines aren't out in all weathers being bounced around in fields etc... they have a cushy life in their sheds, only subject to their own vibrations.

Obviously the less parts, the less things can break down

Yep, that too.

What I don't want is some weird one off injector that I have to send to a lab halfway around the world to get some .00035 part made, and wait 3 months for it to come back

Injectors suitable for Lister CS engines (original & clones alike) are widely available and not that expensive. Eventually, years & years from now, they'll no longer be manufactured brand new, and years & years after that (when new-old-stocks are depleted), any decent machine shop will be able to repair/re-manufacture one-offs; either that or you'll just duplicate one in your Star Trek replicator...

A diagram or drawing would really help me

What do you need a diagram of? The entire fuel system? A whole Lister CS including fuel system? An injector?

Anyway, I hope the above helps. If anyone spots any errors or omissions, let me know and I'll fix 'em.
Cheers!
Ade.
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1x Lister CS Start-o-Matic (complete, runs)
0x Lister JP4 :( - Sold to go in a canal boat.

dkmc

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Re: Theory/Principles?
« Reply #10 on: June 28, 2018, 02:31:15 AM »

Interesting thread....
Not to nitpick, but just to clarify, Common Rail systems operate above 20,000 PSI, and some up to 35000 + PSI. Way above any old style mechanical system, and seems mind boggling that it can be so reliable.



More recently, you may have heard of "common rail" diesel engines - very popular in cars. These have a single pressurised fuel line going to all of the injectors; it's at a lower pressure than a mechanical injector pump will deliver, but still many hundreds of PSI.

Anyway, I hope the above helps. If anyone spots any errors or omissions, let me know and I'll fix 'em.

Machinist, fabricator, designer, fixer

guest23837

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Re: Theory/Principles?
« Reply #11 on: June 28, 2018, 08:16:12 AM »
I dont think you'd need technical drawings to repair and maintain a Lister engine. All manuals give dimensions, clearances and acceptable wear levels more data than you could shake a stick at.

AdeV

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Re: Theory/Principles?
« Reply #12 on: June 28, 2018, 07:01:11 PM »

Not to nitpick, but just to clarify, Common Rail systems operate above 20,000 PSI, and some up to 35000 + PSI. Way above any old style mechanical system, and seems mind boggling that it can be so reliable.


Well, I didn't know that! Although I suppose it makes sense, really, the injector still needs to atomize the fuel, and high pressure is still the best way to do that.

I do know that if you get problems with fuel rails in older Ford Mondeos (becoming a common issue now), it's cheaper to scrap the car and buy another one than it is to fix it...
Cheers!
Ade.
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1x Lister CS Start-o-Matic (complete, runs)
0x Lister JP4 :( - Sold to go in a canal boat.

BruceM

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Re: Theory/Principles?
« Reply #13 on: June 28, 2018, 08:02:15 PM »
Very interesting.
I confirmed the high pressures- 30K Psi is common, but am still surprised.  We used hydraulic systems in those ranges for flight simulator motion bases and safety was a big deal- a leak can cut off a finger or limb in a flash.

1100-1500 psi seems totally adequate, but there must be some method to their 30k psi madness. Part of it is likely and accommodation for the piezo actuators; very small movement/aperture so high pressures used. Piezo actuators have fast response compared to magnetic coils and slugs, useful for finely variable injection timing. I also recall reading about the use of multiple injections per power stroke for better fuel efficiency.




dkmc

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Re: Theory/Principles?
« Reply #14 on: June 28, 2018, 08:20:11 PM »

I think what I read was the super high (relative term) pressures were to atomize the liquid into smaller micro drops which helps it light off more evenly, thus giving better fuel economy and efficiency.
Never have yet seen one of the modern pumps, but they must be truly rugged units to withstand those operating conditions for 200-300,000 miles.
Luckily, no such nonsense on an old dirt simple Listeroid.
Machinist, fabricator, designer, fixer