Accidents involving Listeroids?

[sid]

injection does start before tdc. but to make it a diesel you have  the compression for ignition..it would be hard to get that much compression before tdc..the crank can still push back with a lot force but it is not like a kick back on  a gas engine// sid

[Halfnuts]

Kickback is characteristic of spark ignition engines for the following reason: 
When starting a gas engine, you have an explosive mixture in the cylinder at near the optimum ratio of fuel and oxygen for combustion.  A spark ignites that mixture at a substantial crank angle BTDC, so ignition is very rapid and you can get some spectacular kickbacks.  Ask any Harley rider or antique car buff.

By contrast, when starting a diesel the ignition is pretty sluggish on the first fire.  Probably a good portion of the fuel charge sprayed before the piston is all the way up, doesn't burn right away because the pressure and therefore the temperature in the cylinder are low.  What fuel is still blowing around in the swirl chamber or cylinder headspace lights relatively slowly.  You can see that when you start your engine on cold mornings when you haven't had your Wheaties and it's tough to get good cranking speed.  If the flywheel just barely makes it just past TDC after the injector "pings" the first one or two puffs are pretty weak.  Then the engine begins to accelerate strongly. 

Does that make sense?

Halfnuts

[hotater]

Understand it?  SHO do!

My mini-Petter thumped me pretty good not long ago, but it was a 'shift of the hip' not a mule kick.

I've always let the injector ping three GOOD times before flipping the lifter.   That starts it rich but it works well for me.

[Halfnuts]

Hi Jack,

Then there's the mass of the flywheel to consider.  A high speed diesel like your MP won't have as heavy a flywheel as a thumper will, so funny things might happen during starting and maybe some sort of kickback is possible, but I've never heard of it before.  I suppose if the ignition were advanced a bit too far that might be more likely, so maybe I should have said "properly timed" diesels don't kick back.  But then, an improperly timed diesel won't run well anyway, so that's an anomaly anyway. 

I've had my engine bounce off compression several times when I wasn't really paying attention, but it was the bounce was never powered by ignition.  It gets your attention, though, doesn't it?

Halfnuts

[Julian]

a diesel properly timed will not kick back.

Some of the early lamp start hot bulb semi-diesels are started by bouncing the flywheel against compression in the wrong direction - the intention is for it to fire, not make it over TDC, and kickback and run in the correct direction.

Also,I've got a Field Marshall tractor in my collection, here's an example:

http://www.tractordata.co.uk/field_marshall/pages/field_marshall_3_1950/

It's a two stroke single cylinder, (40BHP/750RPM) starting is with glowing papers and either a handle or cartridge. The decompressor automatically drops to give 1/2 compression for one revolution during starting - it's physically imposible to swing over full compression because it's just too big. If you get it wrong it will run very hapily backwards, you get a lot of reverse gears and one forward gear! You've got to stop it quick because the lubrication pump runs backwards and won't deliver oil. The starting handle is about 3 times bigger than a Listeroid one and reputedly would be thrown clear over the barn roof into the next field!

Some of the early Diesel engines had pneumatic speed regulation, (a venturi in the inlet manifold) if they ran backwards the governor wouldn't control and the engine was often damaged - some of the early Ferguson tractors had this system I think. I've never had the CS 6-1 going backwards yet though.....

[fattywagonman]

Hi Julian,
Nice tractor... So your tractor is a semidiesel like the FM at the top of this page..
http://www.oldengineshed.com/diesel.html

[sid]

some large stationary diesel will run both directions/ I saw one in fla. a few years ago that would reverse. if you were good at it you waited until it was almost stoped and went up on the compression stroke and inject fuel when it was almost stop it would kick back and run in the other direction//also I have a friend that has an electric started for a lister.. because of advanced age he forgets which direction to start it... and puts the starter on the wrong direction.. he has broke 2 idler and cam gears//sid

[trigzy]

The Yanmar service manual for the L100AE series (10HP, 406cc, 3600RPM) specifies that those engines have a cam specifically designed to prevent them from running backwards.  Manual also states that if the engine DOES run backwards, to stop it, as the lube oil pump is spinning in the wrong direction and wont lubricate the motor.  When you pull the starter rope to slowly, it sure does bounce off that compression - and hurt your hand if you are still pulling the rope....

As far as gas engines running backwards the engines on early Fairbanks-Morse railroad speeder cars were actually designed to do that - that allowed you to run the car either direction without need for a gearing system.  There may have been something to change the spark timing - the old guy explaining it wasn't real clear on the technical details.


Steve

[Halfnuts]

Speaking of running engines backwards, an exchange student from Switzerland once told me it was a common prank there for a kid to start his moped in reverse, then sit there idling until a friend walks by and asks to ride it.  When he gives it the gas, he gets a surprise.

Halfnuts

[sid]

the ole 2 cycle golf carts are designed to run back wards for reverse. when you stop the cart the motor turns off and when you press the accelerator it starts up/ if you have it set for reverse that is the way it starts//sid

[Julian]

Hi Julian,
Nice tractor... So your tractor is a semidiesel like the FM at the top of this page..
http://www.oldengineshed.com/diesel.html

No, it's actually a true Diesel. However, it's like a CS 6-1 running on low compression only, ie it will only start without glowing ignition papers (saltpetre impregnated) when it's hot and then only with the aid of a starting cartridge, simply because it would be physically too difficult to hand swing over a full compression. When starting from cold on the handle you need ignition papers.

It sends lovely smoke rings up into the sky and when threshing or ploughing you could hear the exhaust about a mile away!

[fattywagonman]

Hi Julian,
I see... I thought it was a semi diesel like the Lanz pictured here...
http://www.dynapay.com.au/Tony/Lanz/Pictures/2004%20Pics/Henrik's%20D9538%201935%20B.jpg

but it sounds like it's a  2 stroke diesel.. As I'm sure you know the lister is 4 stroke and less likely to run backwards..
Here's some video of the Lanz tractors... I love that they use the steering wheel as the crank...
http://www.dynapay.com.au/tony/lanz/VideoClips/Default.htm

[fattywagonman]

BTW Altopro is rightly justified in being concerned about liability when selling open flywheeled engines... lots of folks now a days aren't smart enough to keep thier hands, feet and kids away from spinning wheels... much less having the technique to crank start an engine.. And Doug there's not an insurance company I know of who would insure you to sell a lister type engine.. the modern kid is raised in a protected world with rubberrized playground equipment has no idea a moving object can cause harm... and that some things are hot and will burn you... My kids know that some things on the steam boat are hot and you just don't touch them... some  kids and even some adults just don't get it.... I don't think they've ever been burned or smashed a finger... we try to figure out who they are.. and not let them on the boat... 

[Doug]

Yikes thats scary Hotater!!!

 I'm glad you weren't hurt....

I always carried a pocket watch in the inner left pocket of my work shirt  ( I wear arm surplus stuff because its got a lot of pokets ) when I work but I used to hook the chain around to the front pocket just to make it easy to reach. One day while crawling around on top of a battery bank I shorted two cells together and smelled something funny. My chain was melting and so was my shirt was smoldering. The mechanics in the shop said I did a funny little dance kind of like a worm on a hot plate as I tried to wigle out from under the battery decks and get out of the truck.....

Doug

[Julian]

Hi Julian,
I see... I thought it was a semi diesel like the Lanz pictured here...
http://www.dynapay.com.au/Tony/Lanz/Pictures/2004%20Pics/Henrik's%20D9538%201935%20B.jpg

but it sounds like it's a  2 stroke diesel.. As I'm sure you know the lister is 4 stroke and less likely to run backwards..
Here's some video of the Lanz tractors... I love that they use the steering wheel as the crank...
http://www.dynapay.com.au/tony/lanz/VideoClips/Default.htm

I nearly bought a Lanz Buldog once, they are quite common in the UK and exporters in Europe are keen to sell to us. I think it's safe to say that the Marshall Single Cylinder Diesel was one step up the evolutionary ladder to the Lanz hot bulb. My Field Marshall was about the last model with the single cylinder produced by Marshall,But earlier models like the Marshall 15/30 dated back to the 30's when the techonolgy only just existed to produce injection pumps as we know them today. They certainly are a tractor with a difference and very unique, in their day they gave the petrol/paraffin tractors with their high fuel consumption and unreliable magnetos a real hammering!