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Its the ball that spans the middle of the chamber. The injector sprays onto it, when cold it atomizes via impact vaporization. When the engines hot that ball is glowing from frequent combustion around it and vaporizes the fuel with that heat.


Thats what makes it different from every other IDI diesel.
Mercedes' design is an actual precombustion chamber, "normal" prechambers are nothing more than swirl chambers; The injector does all the atomization and the prechamber aids in mixing the fuel with the air.


The only reason MB nozzles work in VW engines is the impact vaporization of the fuel against the chamber wall (similar to when the MB engine is cold).
 

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If that ain't cool! I see how it works I think. The fuel charge entering the glowing ball partially burns because there is only so much oxygen there. Then because of the expansion of the gas it forces the rest of the charge out into the main combustion chamber giving it speed and a swirl or some kind of turbulence AND raising the heat, thus aiding combustion. The Common Rail does this in a much more complex way using the computer and multiple injections per stroke with the glow plugs turning on and off in milliseconds. Nice going Mercedes! I could see where a little propane might could help the process with careful tuning.
 
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Glowplugs are only on before starting. Propane doesn't help anything, its just more fuel. Turning up the pump will have the same effect without the risk of blowing up the engine.
 

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Glowplugs are only on before starting. Propane doesn't help anything, its just more fuel. Turning up the pump will have the same effect without the risk of blowing up the engine.
propane can be just more fuel, but it's easier to ignite and provides a good spark, then reducing an eventual amount of unburnt fuel...
 

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Incorrect. Heat alone ignites the diesel and the amount burned remains wholly unchanged.
wrong again. gotta have compression and heat to ignite the diesel. and every time I blow a cloud of black smoke out of my truck its unburned fuel. definately not a complete burn.
Dieselschlepper, I think the reason mercedes do so well is their injection pump is an inline like the p7100, almost indestructable in most cases, along with the "on the verge of too hot" of the IDI setup. they all seem to need way more rad than a DI diesel.
 

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Hi, jubel is referring to the "hot bulb" in the prechamber in the IDI heads on the OM617. That actually lights part of the intake fuel charge, within the oxygen limits of the chamber and blows it out into the cylinder.
 
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I guess IDI is why these engines run so well on WVO and alternative fuels?
No. No engine runs well on WVO. The injection pump is merely more tolerant of garbage being run through it.

gotta have compression and heat to ignite the diesel. and every time I blow a cloud of black smoke out of my truck its unburned fuel. definately not a complete burn.
Wong again. Black smoke is due to excessive fuel injected into the engine when there is a lack of oxygen. No amount of propane injected into your engine under those conditions will increase the amount of diesel burned even in the slightest, in fact injecting propane in that situation would INCREASE smoke by reducing the air:fuel ratio even further!

Hi, jubel is referring to the "hot bulb" in the prechamber in the IDI heads on the OM617.
No. The bulb doesn't light the diesel, it atomizes it.
 

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No, I meant the hot bulb helps with the WVO. That's why I said "IDI". You can have IDI with any style pump.

So the difference between diesel to the hot bulb and propane is the propane will light off instead of separating into atomic constituents?

That's true; it could have been said a long time ago.
 

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Interesting reading.

i will be giving this a try on the 4-53n when it's installed being as my Vehicle is allready outfitted with all Lpg components for the gas engine.
Anyone have pressure to orfice sizes they have experimented with. i'm pretty sure my regulator/converter puts out around .37kpa. this is much less than 1psi.
i could run some sort of throttle blade within the lpg feed line from converter to orfice to meter the lpg.

if you don't like propane that is understandable but please personal opinion is not fact. anything without moderation is not good

thanks
Chris
Cb9wagon
 

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Yes Chris: That party is no longer with us as you may notice. The hot bulb in the Mercedes makes it different it seems, but propane seems to work on other types of diesels.
 

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Here in Australia we use LPG (liquid petrolium gas) proberly the sam as your propane, I nhave it on my 4.2lt idi Nissan Pootrol, It is a comercial type of set up but it works well. If your driving at a set pace and turn it on or off you can feel the differance in the power output. And their arnt any scary side effects to your engine. Even the government were actually giving rebates to those who had the units set up by a qulified dealer. Were i live some of the truking companys have had them installed on there big Rigs and they run tripple trailers, Ive actually heard that they run the gas through a Water air intercooler instead of the water to keep things a little cooler (though it ices up on the out side in winter aparently). S the main thing I see is trying not to put to much in and causing the engine to ping/ preignite but that wouldnt be to hard to stop. You would have to have a manual valve in the cab so when you want the gas you flick your switch and adjust the valve to the point you think is a good thing and listen for preignition (might be slightly harder if your donk is a bit noisy)
 

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That coment, no diesel runs well on VO is false. I've been running it 2 years in my 99 ctd and get 24 to 26 mpg and it pulls my 5000lb travel trailer with no problems. If you have a well engineered system and clean dry oil, you have no problems and its free fuel.
 
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