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-   -   Leaking IPs, LSDF and you. (http://www.peachparts.com/shopforum/showthread.php?t=104394)

R Leo 09-25-2004 05:37 AM

Leaking IPs, LSDF and you.
 
LSDF (low sulphur diesel fuel) issues.

http://www.med.govt.nz/ers/oil_pet/lower-sulphur-diesel/meeting-20030429/index.html

tomm9298 09-25-2004 06:24 AM

Hmmmmm....
 
I will try to avoid politics here, but when the government is run by people with a large financial stake in oil companies, it will be difficult. In Germany the government gives a tax break for diesel users at the pump, not so on gasoline taxes. The idea being that to reduce dependance on foreign oil it would be best to cut consumption. Enter the effeciant diesel engine.
Now, lets play with the sulphur content and make pumps and seals leak in older diesel engines. The text following is a direct copy and past from the link above......:

Engines That Could Be Affected

At a broad level, the seal in any fuel injection system in any diesel engine might be at some (although in many cases negligible) increased risk. This includes not just on-road vehicles such as cars, trucks and buses but also tractors, pumps, boats and generators.

However, it is believed that many of these off-road diesel engines do not experience the same amount of wear and tear on the vulnerable throttle shaft seal and so are less likely to experience seal failures. With regard to on-road engines the predominant risk will be experienced by light diesels (3 Litres or less) but a small group of heavy-duty vehicles with in-line pumps may also be at risk. :eek: :eek: :confused: :(

R Leo 09-25-2004 07:32 AM

No political agendas. I'm just trying to get some information out about LSDF, biodiesel and their potential effects on IPs so that we don't inadvertently kill our IPs. For grins, I've got a Robert Bosch inline injection pump book on order to try and determine the locations of the seals and o-rings in these IPs.

FWIW, at lunch yesterday, I stopped off at Central Texas Diesel Injection Service (CTDIS) to ask a few questions about their experiences with bio-fueled (SVO and Biodiesel) vehicles. I found out some interesting things...

In the last year CTDIS has serviced two vehicles which had experienced IP failures that they attributed directly to the use of biodiesel. One was an International-powered school bus, the other, a late model Mercedes-Benz (I didn't find out if it was a CDI or IDI engine). The bus was making a x-country trip and supposedly had a fresh engine and, I assume, a fresh IP as well. The owner of CTDIS said that he had never seen a new IP as badly worn as the one from that bus. He attributed the failure to a lack of acceptable lubricity in the biofuel. The Mercedes was not dissasembled and no autopsy was performed. It returned to the dealer for a replacement pump.

As far as CTDIS knew, they had not worked on any straight SVO powered engines yet.

At this point, CTDIS recommends using Stanadyne Performance formula to make up for the lack of lubricity in low-sulphur diesel and an assumed lack of lubricity in biodiesel.

Regarding my question on rubber in IP and other fuel system components....
Most, if not all currently produced diesel IP have viton seals and o-rings. Older Bosch IPs, such as those on the 615, 616, 617 and possibly some 60X engines have seals made from Buna-N.

Based on this knowledge, I did some research on Buna-N, or nitrile, and discovered this:
Buna N or Nitrile, is a copolymer of butadiene and acrylonitrile. Acrylonitrile content is varied in commercial products from 18% to 48%. As the nitrile content increases, resistance to petroleum base oils and hydrocarbon fuels increases, but low temperature flexibility decreases. Due to its excellent resistance to petroleum products, and its ability to be compounded for service over a temperature range of -65 to + 275 degrees F (- 54 to +135 degrees C), Nitrile is the most widely used etastomer in the seal industry today. Most military rubber specifications for fuel and oil resistant MS and AN 0-rings require nitrile base compounds. It should be mentioned, however, that to obtain good resistance to low temperature with nitrile compounding, it is almost always necessary to sacrifice some high temperature fuel and oil resistance. Nitrile compounds are superior to most elastomers with regard to compression set or cold flow, tear and abrasion resistance. Inherently, they do possess good resistance to ozone, sunlight or weather but this can be substantially improved through compounding. However, since ozone and weather resistance are not always built in, seals from nitrile bases should not be stored near electric motors or other equipment which may generate ozone, or in direct sunlight.

Nitrile Is Recommended for:
General purpose sealing.
Petroleum oils and fluids.
Cold Water.
Silicone greases and oils
Di-ester base lubricants (MIL-L-7808).
Ethylene glycol base fluids (Hydrolubes)

Nitrile is not recommended for:
Halogenated hydrocarbons (carbon tetrachloride, trichloroethylene)
Nitro hydrocarbons (nitrobenzene, aniline)
Phosphate ester hydraulic fluids (Skydrol, Fyrquel, Pydraul).
Ketones (MEK, acetone)
Strong Acids Ozone
Automotive brake fluid.


Source:Scientific Instrument Services, Inc.

R Leo 09-25-2004 07:45 AM

BioDiesel Lubricity
 
1 Attachment(s)
Soy based biodiesel lubricity (from here)

bill murrow 09-25-2004 08:27 AM

Thanks R Leo. Information I really didn't want to know but we all better pay attention!

Where is the best place to find Stanadyne? I'll be adding some to every tank. Just be thankful they can't mess with the sun-they would have us all freezing or burning up!!! :D

Cheers,

Bill

R Leo 09-25-2004 08:55 AM

Quote:

Originally Posted by R Leo
At this point, CTDIS recommends using Stanadyne Performance formula to make up for the lack of lubricity in low-sulphur diesel and an assumed lack of lubricity in biodiesel.

Obviously now, this aint so.

R Leo 09-25-2004 08:58 AM

Quote:

Originally Posted by bill murrow
Thanks R Leo. Information I really didn't want to know but we all better pay attention!

Where is the best place to find Stanadyne? I'll be adding some to every tank. Just be thankful they can't mess with the sun-they would have us all freezing or burning up!!! :D

Cheers,

Bill

You can probably find the Stanandyne at your nearest injection service hut or truckstop.

TwitchKitty 10-07-2004 12:07 PM

Bump, thanks for the link to this thread. I missed it while I was out of town.

Rick Miley 10-07-2004 01:22 PM

Quote:

Originally Posted by R Leo
One was an International-powered school bus, the other, a late model Mercedes-Benz (I didn't find out if it was a CDI or IDI engine).

Unless it was from a Sprinter, it would have to be IDI. The E320 CDI that just went on sale a few months ago is the first passenger car CDI they've sold here.
Quote:

Originally Posted by R Leo
The owner of CTDIS said that he had never seen a new IP as badly worn as the one from that bus. He attributed the failure to a lack of acceptable lubricity in the biofuel.

WHAT?! Everything I've read says that biofuels have much more lubricity than #2. The chart you included is pretty, but what do those numbers mean?

Habanero 10-07-2004 01:44 PM

Yeah, I have seen data showing biodiesel to have almost an order of magnitude better lubricity than regular #2, so they are full of crap on that issue. I have talked to countless older mechanics who try to find anything they can wrong with any new fuel, so being dismissive of biodiesel as bad for the IP wouldn't surprise me. My dad was the same way when ethanol blends started showing up in Iowa (although he did have a point in the case of older carburated engines with the foam floats that would dissolve in ethanol). It took him years to admit ethanol was okay even for modern fuel-injected cars.
As far as what really did cause the wear in that IP on the bus, it is hard to tell. Could have been a bad batch of fuel (bio or petrodiesel) that had a lot of water in it. Could have had massive fuel filter failure. Could have been any number of things, but I would bet the farm it was not the simple fact of using biodiesel.

On edit: I just looked at the data provided above and even that shows biodiesel to have much better lubricity. The scar number being smaller means there was less wear, therefore better lubricity. The friction number was about half as well. In those two instances, smaller numbers are better.

R Leo 10-07-2004 01:45 PM

Rick,
I think the chart pretty much proves that Biodiesel has superior lubricity than LSDF. After reading that info, I decided that CTDIS was uninformed about biofuels in general. Indirectly, their lack of knowledge is addresed further back in this thread.

R Leo 10-07-2004 01:53 PM

I agree with Hab, that bus IP brobably died because of bad fuel/filtering/Lord knows what. After the research I've done, I damned sure don't think it was a lack of lubricity on the part of biodiesel. Additionally, the facts are mighty thin when it comes down to what caused that pump failure, the age of the pump and what the fuel source really was.

FWIW, home brewed biodiesel is problematic at best. It takes a lot more effort than the so called "biodiesel kit" manufacturers let on to produce consistent, high quality b-100. However, even ASTM fuel (bio or dino) can be nasty since ASTM certification is only required on an annual basis.

R Leo 10-07-2004 01:58 PM

The rest of the story...
 
What this all means is that LSDF has virtually no lubricity and, some sort of additive should be used in fuel to offset the lubricating quality of the missing sulphur. Whether you dump in 2-stroke oil, ATF, B100 or Crisco is up to you and your research.

I think that I read all Euro diesel is basically B2 because the refineries are adding biodiesel to the #2 for its superior lubricating qualities.

TwitchKitty 10-08-2004 01:10 AM

My perspective is that LSDF is like winter blend or kerosene and we should treat it the same way. Sound about right?

I didn't realize this was happening now. The new diesel emissions standards make it necessary but I thought it was still a ways off in the future.

http://www.platinum.matthey.com/media_room/1096470002.html

Quote:

The US is still on course to meet its schedule for implementing ultra low-sulphur highway diesel fuel, the Environmental Protection Agency (EPA) has announced.

Under its "Clean Diesel Programme" the EPA is aiming to reduce 2.6 million tons per year of nitrogen oxides emissions from diesel exhaust.

The agency says that its target to make the change during the next five years - the equivalent of eliminating air pollution from 13 million trucks - is on track.

In its latest report, "Summary and Analysis of the 2004 Highway Diesel Fuel Precompliance Reports", the EPA says that by 2006 a total of 95 per cent of all transport diesel - 3 million barrels per day - will meet the 15 ppm sulphur-content standard in 2006.
http://www.americansweeper.com/v3n1/v3n1lowsulph.html

Quote:

Dick Walker, Branch Manager with a Detroit Diesel, Perkins and Allison engine distributor, says that "probably almost every engine model of most all makes and brands is going to experience some problems if they use Buna-N in any of their seals. So far, it looks as though engines which have always used low sulfur fuel as their primary fuel are okay. High sulfur fuel swells the seal ring up, and then switching to low sulfur shrinks the seals and cracks them." So far he has not seen any failures of Perkins auxiliary engines which fit the profile of this condition

Hatterasguy 10-08-2004 10:19 AM

When is LSDF going to be phased in here?

Also I thought our IP's were oil lubricated?


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