Low Sulphur Diesel Fuel vs older MBZ Diesel - PeachParts Mercedes-Benz Forum

BeachnCruz · #1 01-08-2005, 05:51 PM

Is the apparent push toward low sulphur diesel fuel going to make our older MBZ diesels obsolete eventually or will higher sulphur content in diesel still be available for us with older diesels in future years ?

Jim....

pawoSD · #2 01-08-2005, 06:11 PM

I'd think the only problem would be that the sulfur free fuel has less lubrication right? So thus if I continue my practice of dumping a whole bottle of mystery oil into the tank each time I fill up, I won't have lube probs since the mystery oil is made to do that....? I'd assume it'd be ok with an additive in there to help the lubrication....and it will certainly smell better!

lrg · #3 01-08-2005, 06:25 PM

A good additive will solve your problems, just like pawoSD said. There are several good brands so I'd recommend a search on the topic rather than our starting our second favorite "discussion" (after what kind of oil to use). It's basically the same concept as for those of us who have old geezer cars that needed lead in the fuel. With the right additive unleaded is just fine.

rg2098 · #4 01-08-2005, 06:37 PM

I believe the sulphur was to lube IP's that are fuel lubed, our Bosch pumps are oil lubed so there should be no problem.

TomJ · #5 01-08-2005, 06:53 PM

As far as lubrication, only a 2% concentration of Biodiesel added to ULSD will have 30% BETTER lubrication characteristics than the old sulphur diesel.

So..., for the price of $3/gallon (or less in many places), it's the cheapest lubrication additive you could come up with (in comparison, MMO, good stuff, costs about $3/quart!)

Not only will it NOT make our vehicles obsolete, it'll FORCE us to use an additive that will clean the fuel system, increase cetane and overall increase the longevity of the engine., so it's a GOOD thing!

pawoSD · #6 01-08-2005, 07:43 PM

So we can just fill our tanks up with the sulfur free when it comes around, and have no "problem" except cleaner exhaust?

Jimmy Joe · #7 01-08-2005, 11:11 PM

Let me guess, ULSD stands for "ultra low sulphur diesel"?

pawoSD · #8 01-09-2005, 01:20 AM

When are we actually going to see this stuff appearing at our local diesel pumps? Anyone have an idea on when its going to be largely phased in?

Veloce300DT · #9 01-09-2005, 02:06 AM

Arco is now carrying low sulfur diesel at many of its locations in California.

Ive been using it for the past 2500 miles, along with a bottle of BG diesel additive with every fill up. The combination of the 2 has substantially reduced engine noise, highly increased smoothness, and there remains to be a healthful amount of power, and low soot levels. Im loving it!

Id be tempted to say that with a finely tuned 617 engine, running on low sulfur diesel and an additive, has made the noise level of the engine comparable to a newer TDI engine, but its not quite THAT quiet. The reduced noise is most noticable at higher speeds- 65mph and up and you dont need to crank up the stereo too much anymore! And the throttle seems soo silky smooth when depressed and floored, with prompt power delivery. Im loving it!

Gurkha · #10 01-09-2005, 04:39 AM

India switched to low sulphur from 1996 onwards and have been running that on my OM 616 since then without any ill effects whatsoever.

P.E.Haiges · #11 01-09-2005, 08:56 AM

rg2098,

Its only the mechanical parts in the bottom of the fuel pump that are lubed by the engine oil. The plungers and barrela are lubed by the fuel. Thus wherin lies the problem. The sulphur in the fuel helped to lubricate the barrels and plungers. The non IP engines do not need the sulphur and whether the fuel refiners will put in additives for IP engines is unknown.

I add filtered used engine oil to my fuel. It serves 2 purposes: gets rid of the used oil and lubes the plungers and barrels if the IP.

P E H

dabenz · #12 01-09-2005, 10:14 AM

2006 is when the US is supposed to go to the next step in "low" sulphur. Still won't be as low as european standards, but it will be low enough to make a catalytic converter effective, meaning we might see more diesels in the new auto market. If the US diesel auto market takes off then we'll have a big problem in the US: refinery capacity. We've already seen the effect of the refineries not being able to produce a reserve of heating oil for this winter, which is higher road diesel prices. Current refinery capacity can barely keep up, thanks to emissions laws and "not in my backyard" attitudes toward new construction.

PEH has it almost correct. It's the seals for the plungers that needed the sulphur. Trucking industry had a big mess when the first change to low sulphur was made. New seal materials and a lot of labor installing them fixed that problem, not additives. But lubricating additives, whatever the type, will help our old diesels.

jayb79 · #13 01-09-2005, 12:49 PM

Our MB piston pumps do not have a problem with ulsd, true only the lower mechanicals are oil lubed but that is were all the work is done (just think about your crankcase full of oil and the pistons that only see fuel and air).

The problem with ulsd is on rotary pumps. They are used on VWs and most V8 small trucks. I don't know about common rail pumps.

I think a small percentage of biod is a great idea for anyone worried about lube. I have read studies that show a remarkable increase in rotary pump life with as little as 3% bio added to the fuel.

TomJ · #14 01-09-2005, 02:32 PM

Quote:

Originally Posted by jayb79

Our MB piston pumps do not have a problem with ulsd, true only the lower mechanicals are oil lubed but that is were all the work is done (just think about your crankcase full of oil and the pistons that only see fuel and air).

The problem with ulsd is on rotary pumps. They are used on VWs and most V8 small trucks. I don't know about common rail pumps.

I think a small percentage of biod is a great idea for anyone worried about lube. I have read studies that show a remarkable increase in rotary pump life with as little as 3% bio added to the fuel.

The actual fuel pistons/del valves on the Merc pump are lubricated by the fuel and there will be some wear just from having a little less lubrication in the fuel, the question is whether it will be perceptible or not. Also, mfg's are "supposed" to be adding some type of lubricant to replace the sulphur and most are finding Biodiesel to be the cheapest alternative for that.

The way I look at the Biodiesel, besides the enviro and lubrication positives, is that it's X% less in $'s I'm sending overseas for some religious nutcase to use to kill "great satan America." Allegedly though, we get less than 10% of our oil from the ME, most is from South America and Canada.