Is there a specific diesel fuel additive for mercs? i was told there was such a thing and it gives extra lubrication tothe fuel system, pump, etc. Is there such a thing?

 

Adda qt or even a gallon or two ofsoy saladoil. It has a high cetane value and you'll know it's working because the IP and engine will be quieter. Costco has soy salad oil in4.3 gallon containersfor about $17.00. BTW, I ran my VW on pure salad oil. It was still purring like a little tiger when I sold it at 167000 miles on the od...and I now run WVO in Bruno, my old MB 300D T. and ol' Bruno purrs like a big Tiger...He now has over 321,000 on his od and I don't need to add oil between changes..

If that spooks you, then run about 10% or 20%biodiesel, which isveggie oil without the glycerin...

 

I run Power Servicesupplement in winter -- you can get it at Wal-Mart. It has a cetane booster, a lubricating factor and an anti-gel agent which is helpful during the cold weather.

Be careful adding vegoil of any type when the weather is below 45 degrees as it will lower the cloud point of your diesel fuel and make starting your engine very difficult. It can also clog your filters, IP and injectors thereby crippling your engine.

 

http://www.energy.psu.edu/tes/cetane.html

worth a read if your in the mood for something slightly technical with your morning tea.

 

You're most probably right, but there's no doubt that my old 300DT runs much quieter when using veg oil, which seems to indicatethe ip and engine may like a bit of additional lube...Veg oil also does a good cleaning job.... ridding the fuel tank and lines of soot...It takes a few miles beforethe lines and tank are finally clean so, depending on how dirty it is,you'll also have to replacea few fuel filters. Of course bio diesel has the same effect, but, IMHO, is much more abrasive. But either or both are good additives, and also cut down on emissions as well as being carbon neutral.

During the summer I use 100% veg oil. In the winter I use 90%veg. ( I live on the Pacific North West, coldest so far this winter whereI livewas around 20 degrees F.) I installed mercedessource.com modules, using the original fuel tank as the only fuel source. Granted, it's still experimental, especially atsujch ahigh percentage of veg oil, but so far the systemhas performed flawlessly.

 

All injectors presenta coked ring. Regardless of the fuel burn, it's a normal occurance. The picture you've presented, where the ringis slopping over and is not a precise circle, indicates that the heat shield is failing.... and that has nothing to do with the type of fuel.

I also installed a 2 tank system in my creampuff 1990 Jetta ecodiesel, and drove it for over 35,000 miles, finally understanding that constantly heating and cooling veg oil is a major problem in itself, which eventually causes a green substance to form in the tank, etc..... and it's little more than a Rube Goldbery device..

Yet I do preheat the veg oil. It's first preheated veg oil in the sump chamber. I replaced the 5/16" fuel line coming from the tank, to a 1/2" fuel line which allows even near frozen veg oil to gravity flow into the heated fuel sump chamber, then into a clear filter, then into the electric fuel boost pump. then into another clear filter, then into a stanadyne water separator filter, then into another gp heater, then into the IP...

Still, with all of that...The veg oil only needs heating in order to get it to flow, and to extend the life of the water separator filter. Grantedf, the first few minutes before the engine reaches operating temp, the oil should be heated at the fuel injection lines...That can be done with in line heaters.

But after the engine is at operating temp, the natural heat, measureed with an infra temp gauge, at the outside of the IP is 120 degrees, and the natural temp of the injection fuel lines is just about 200 degrees. That means any fuel, including Veg oil, is instantly heated to 120 at the IP and to 200 degrees when it enters the fuel injection lines ...

So, IMHO, except to get and keep the fuel flowing, and to extend the life of the water separator filter, the need to preheat veg oil, other than the first few minutes until the engine heats up ( which is easity done by in line heaters ) ... Preheating veg oil after the engine is warm is a myth, probably created by those who sell heated 2 tank systems, and unnecessary unless there is a fear that it gets so cold that the veg oil solidifies.

That problelm can easily be addressed by adding a small 5 gallon marine tank in thetrunkfilled with diesel...plus. asoliniod to switch fromveg oil to diesel ... and in my case,simplyflip on the return fuel switch on my dash... which will sendheated fuel to the tank and quicklyliquidize it.

But even with that system, the purging is unnecessary provided one has in fuel line injection heaters... which can be bought from mobetta at schumanautomotives.com for $25.00.