Low Sulphur Diesel

[SeaEric]

We have received a letter from the marina advising their change over to dispensing Low Sulphur diesel at the fuel dock. The letter makes some vague references to "perhaps the need" for additives for use in our boats. Does anyone have any experience with this and what the possible ramifications are of using Low Sulphur fuel?

 

[SKYCHENEY]

You are already running low sulfur fuel. The switch would be to ultra-low sulfur. High sulfer fuel was phased out several years ago.

 

[yachtsmanbill]

Hey SKY! Is that ULSD going to affect us up here? Will we need to supplement? It'll probably turn into a "valvetech" thing at the pumps. Hope that alkie deal doesnt happen too! ws

 

[SKYCHENEY]

Bill,
Right now all on-road fuel must be ULSD, but the off-road can be LS until 2011(I think). You will see them phase it in slowly to the off-road market but it is not SUPPOSED to cause any problems. The main difference is that you lose the lubricity when you take out the sulfur. That is made up with additives that the refiners have to put in so that the fuel will meet ASTM specifications. The specs, however, were debated for years. Some of the injection system companies wanted more lubrication additives than what the government settled on.

So, I think the answer is to keep using Diesel Kleen. It will add some extra lubricity to the fuel as well as bumping up the cetane. FYI, the ULS will also cause your mileage to go down slightly. Isn't that nice?--pay more, get less.

 

[Plan B2]

Has anyone ever had any experience with a "Fitch Fuel Catalyst"?
They claim is improved lubricity and kills bacteria often found in fuel aboard a boat. Their performance numbers are impressive, up to 12% improved efficiency. They get a little pricey for the mains but if they deliver they might be justified for the generator.
Does anyone hear have any personal knowledge or experience with sucha device?

 

[Genesis]

The ULSD is fine in older engines. If you want run some DieselKleen in there with you. Newer motors (e.g. the common rail motors now made) will have no issues at all; older ones are unlikely to as well, but the DK won't hurt anything and its reasonably cheap.

 

[NAN-PO 41]

We had a mandatory switch over to ULSD here in Mass. on Oct 1. We had a meeting with our local supplier prior to the switch and what we were told at the meeting was that if you are running an older diesel there is a lack of lubrication for the pumps and injectors. This can be remedied in either of two ways. You can use an additive ( such as Dieselkleen ) or you can buy 10% biodiesel mix. (apparently the 10%bio adds enough lubricant) The newer common rail diesels are not supposed to have any problems swallowing the ULSD.
Now comes the glitch. The ULSD will clean the tanks. (Sounds vaguely familiar to an ethanol problem ) The results of this cleaning will end up in the filters ( hopefully ). You can expect to clog filters at a faster rate until the tanks are clean of the asphaltine drop out which will become suspended in the fuel.
I haven't seen any problems as of yet in our 1976 workboat but it is early in the process. I will post any problems that I encounter as time goes on. We put more hours on the workboat than the Hatt so anything that happens should show up there first.

At any rate that is what we have been told by our supplier.
Good Luck, Fred

 

[MikeP]

Somebody is trying to sell additives! Nothing is necessary. Here's a quote from Diesel Progress, North American Division, May 2007:

"In markets where ULSD is the only fuel available, using the fuel in 2006 and older engines has no adverse effect to the engine, but there are no significant emissions benefits either. "There is a little bit of emissions reduction because it's lower sulfur and you will have lower emissions," said Schaefer. "But, when you get to the model '07 vehicles with the new aftertreatment technology, that is where you get a big emissions reduction."

The article also explains that lubricity additives are already added to the fuel as part of the fuel spec. So anything further is unnecessary for that purpose. The complete article is here:
http://www.encyclopedia.com/doc/1G1-164220069.html

Diesel Progres' website is here: http://www.dieselpub.com/dp/index.asp

 

[Genesis]

Yep.

There is a small lubricity difference but its SMALL and at least on Detroits, you do not need to do anything.

The other thing to be aware of is that the Cetane Index is higher so you don't need the cetane enhancement. You might even notice that your engine behaves better on a cold start and runs a bit cleaner - but the differences are not large.

 

[Boss Lady]

Adding B100 will provide all the lubrication you would need. I found a local guy who will haul 400 gallons at a time, and his price is only $2.00 a gallon. Which is cheaper than diesel fuel, better for your engine and the environment.

 

[Boatsb]

Does he have a counterpart in the space coast area?

 

[Boss Lady]

Google up Bio-diesel co-operatives in your state, and user groups for it. You will find somebody in your area. It only costs $0.50 a gallon to make your own, and if you can resource the raw cooking oil, they will give a credit on each gallon at the co-op.

 

[Brian Degulis]

We used to run straight K1 Kerosene in Detroits on charter boats when drift fishing in inland waters. The engines would idle while fishing they had to be kept running to corect the drift. The kerosene served two purposes it cut down the exhaust smell and reduced loading up at idle. No aditional lubricant was added and we ran for thousands of hours on it. In the older Detroit manuels Kerosene was aproved for low temperature operation. I'm thinking the ULSD has got to have more lubricating qualities that Kerosene so I wouldn't worry about it.

I put a tank of ULSD in my ford truck it ran quieter and cleaner and I saw no differance in MPG.

Brian

 

[Norm Mayer]

My understanding of ULSD is it is fine in any engine newer than 1990, But expect trouble with O rings and seals in older diesels. Further, in light trucks at least, they say to do a thorough inspection of the entire fuel systems for leaks 90 days after making the switch, as they see many leaks develop in that time frame. I teach this stuff, so I try to stay up with developments. I plan to contact DD to see what they have to say about ULSD in my 1970 8V71's.

 

[MikeP]

Although I don't know anything specific about this - it is possible that USLD has less of the substance in it that causes o rings to swell. ATF, for example will make an o-ring swell considerably - if you toss a new oring into some ATF and, 10 minutes later, try to install it, it will have expanded to the point where it will not fit. So ULSD may not expand the orings as much as the old stuff. By the same token, it might de-expand an existing o-ring. That won't matter at all if the orings are are new or in good shape because whatever de-expansion occurs, it won't get smaller than it was when new. But old, brittle o-rings could crack if "de-expanded" which could create a leak.

So I wouldn't be at all surprised if there were some leaks associated with this but it's not really because of anything bad about ULSD - it's about old O-rings. Admittedly, if the fuel didn't change, the old, brittle O rings probably wouldn't start leaking - at least for quite a while longer.

 

[Avenger]

We saw a lot of this in the switch to Low Sulfur Diesel in '94 (I think) The problem was mostly in O-rings made of Buna-Nitrile rubber, and only in older ones. The aromatics in the higher sulfur fuel had made those O-rings swell, then when they hydro-treated the fuel to remove the sulfur it also took the aromatics out. Those swollen O-rings then shrank. If the o-ring wasn't too old it had enough elasticity to maintain its shape. Older O-rings that had been swollen for a long time had become distorted and would not seal once they shrank. We would replace them with the same type and material of O-ring and they didn't have further problems. Most manufacturers are using Viton O-rings today which are less prone to this. Also, the sulfur reduction is not as dramatic this time around.

BTW, it is very unlikely that any of you are still getting Low Sulfur Diesel. Due to manufacturing and pipeline considerations the major refiners are only making ULSD. While it is possible that some small refiners are making "boutique" fuels. It is more likely that your supplier is selling ULSD without calling it that because of handling and storage. Getting certified to put ULSD labels on your pumps costs money and if it's not a requirement nobody is going to spend it.

Okay, last subject. Lubricity. ULSD has unacceptable lubricity. To meet the ASTM standard for lubricity an additive is used. No oil company is going to use more additive than necessary to meet the standard becuse......wait for it.... it costs money! Fuel injection manufactureres pushed for the european standard for lubricity which is much higher, but they lost to the oil lobby. So, I would still recommend an additive even for older engines. Poor lubrication is slow death to a fuel injection system. Granted if you only run 100 hrs a year it probably will not make much difference.