ULSD clogging filters at 0-10 degrees

[moeh1]

The local buses weren't running this week until they mixed ULSD Kero in with the diesel. See Cold Freezes Bus Fuel—Closes Schools - 13WHAM.com

 

[Bob_Young]

The question is:

If they can't do the science in advance to determine the problems ULSD might cause and how to avert them; then how do we know they did the science to prove ULSD was needed to begin with?

Is this all just political?
Bob

P.S. Pleeeze, don't justify it with what Heidi Cullen says

 

[MadReferee]

If they can't do the science in advance to determine the problems ULSD might cause and how to avert them; then how do we know they did the science to prove ULSD was needed to begin with?

Their problem most likely has nothing to do with the science to prove anything about ULSD. Old LSD diesel would have done the same thing.

I'll wager the ULSD that the bus company is using is summer blend. They probably bought a significant quantity in the thousands of gallons in the summer to beat the winter price increases. Serves them right for not properly maintaining their fuel with some additives like Power Service. Anything to save a buck.

 

[SkyPup]

LOL

Serves 'em right, too bad they don't have something better they could try to blame their problems on.....at least the kids got a day off from school due to their poor planning.

 

[themichelob]

I can't see how this has anything at all to do with ULSD. All diesel fuel will gel at low temperatures if not winterized, regardless of the sulpher content. Let's not try to make it political...

 

[DieselPower]

Actually the gel point of ULSD is higher than LSD. I have seen a couple of lab reports that showed the average gel point of untreated fuel was 7 degree's F.

The real problem is that this was known a long time ago. Every diesel technology magazine, school bus contractors magazine, trucking magazine and power generation magazine I get has had articles in them for month's about ULSD and most all of them noted the higher gel point. They can't say the information wasn't out there.

It is a shame that they had these problems but if they had properly planned in advance they would have been adding pour depressants to their fuel before the problems occured. Poor planning leads to problems just like this.

 

[SkyPup]

The ULSD gel point is slightly higher because it contains allot more paraffins and allot less aromatics, in other words, it is much more like diesel fuel was prior to the Arab Oil Embargo back in the '70's when refiners resorted to more cracking.

 

[Bob_Young]

Are you sure this is all about planning? This week's temperatures haven't been at all uncommon for this area this time of year. Managers of diesel fleets have to be prepared for temperatures as low as -20 F. as it can and has happened. A bus full of children stuck on a country road in a dead bus in NY snowbelt weather is a nightmare scenario. You better believe they've heard of fuel gelling and are concerned about it.

Multiply that by 20 or so busses in each of 17 plus school districts and people from Florida "LOL". I'll remember that come hurricane season.

Usually each school district here operates its own fleet of buses. Historically they've done very well in operating reliably and without incident. I might believe there might be a transportation manager in one or two districts that weren't prepared for ULSD gelling characteristics; but 17 districts? C'mon!

Could be there's something more to this. We're not all stupid up here.
Bob

 

[DieselPower]

Their problem most likely has nothing to do with the science to prove anything about ULSD. Old LSD diesel would have done the same thing.

I'll wager the ULSD that the bus company is using is summer blend. They probably bought a significant quantity in the thousands of gallons in the summer to beat the winter price increases. Serves them right for not properly maintaining their fuel with some additives like Power Service. Anything to save a buck.

I seriously doubt they are still using old summer blend (unless they have a very poor fuel supplier, who knows). A very close friend of mine has a fleet of 33 school bus's and he goes through about 4,000 gallons of fuel per week. Fuel goes fast in a bus. Bus's are on the road a good part of the day and use quite a bit of fuel. His fleet averages about 6.5 MPG.

As for the LSD gelling also, I would also doubt that. The new ULSD has a much higher gel point compared to LSD. Here's a lab report that shows untreated it gel's at +7 degrees F. Could LSD have gelled, sure, but not as easilly as ULSD.

Bob_Young - I'll find out more tomorrow about their problems. I called the superintendant of schools (Dr. Graham) today and he is going to give me a call back tomorrow to talk about their problems and see if there is anything I can do to help. I'll keep you updated what their reply is.

 

[Iowachild]

ULSD is coming right off the treating unit at our refinery with a cloud of -16 degrees F and a pour point of -34 degrees. The "all weather diesel", treated with among other things a pour point improver, had a pour point of -44 degrees F yesterday. BTW we have a terminal in Rochester, NY.

 

[dholly]

Mike, I may be misunderstanding but are you saying that the difference in pour point of summer vs. winter blend is only +10F? Exactly what does -34F pour that mean TO ME in practical terms with itty-bitty i.d. fuel lines and filter media? While the kids were enjoying their day off, the -11F had me wondering whether either my tractor (parked inside unheated garage with the last of my untreated summer blend in the tank) or my truck (winter blend with 1oz. Power Service per 3 gals. parked in the driveway), neither of which were plugged in, were going to have a problem starting. Both started fine but took a while to warm up, just like Papa!

 

[Z-Michigan]

Seems to me that either the districts got summer fuel (perhaps unknowingly, maybe the supplier screwed up) or the temperatures were far lower than reported. Here in Michigan we had lows around -8 F. earlier this week. Both my vehicles are diesel and both were outside that night. Both started without any sign of gelling - they were COLD, but they started and ran fine. I had put Power Service anti-gel in one (which defeats the example!) but not the other. I haven't heard any reports around here of any trucks or buses having fuel problems.

 

[john_bud]

Big problems with fuel here in WI too. I had to put my truck in a heated shop for 24 hours to get it all the way back - that's after adding 1 qt of PS white AND 1 qt PS 911 AND changing fuel filters. After the new filters and additives, it went 100 yards down the road and set a "low rail pressure" code. Meaning the new filters were clogging. The original gel was with fuel bought here that I added 6 oz of PS white to 22 gal of fuel - before it gelled. No water in either filter.


ALL of the major suppliers of additives around here have been selling out. Walmart, Kmart, etc are OUT of diesel 911. PS is flying off the shelves. Had to go to 3 places to get some Howes and a few more to get FPPF total power. Local garbage hauler bought up ALL of the additive inventory from CATCO that said anti-gel on it. They just got more in as I was there. Everybody is saying it's the worst ever spate of fuel related issues. They are thinking that the suppliers didn't add the dope to the fuel.

Remember, this is WISCONSIN and -15F or even -20F isn't a big deal. But, there are more trucks and busses gelled than ever before. why?

jb

 

[DieselPower]

ULSD is coming right off the treating unit at our refinery with a cloud of -16 degrees F and a pour point of -34 degrees. The "all weather diesel", treated with among other things a pour point improver, had a pour point of -44 degrees F yesterday. BTW we have a terminal in Rochester, NY.

That may be very true but not all ULSD that is hitting the pumps has a pour point that low. If the fuel you are talking about comes from PA crude it is naturally lower in paraffin's and higher in aromatic's which lead to lower pour points. However, not everything that is being dispensed is that good. The horrible problems some people are having with temps in above 0 degree F. weather this last weak is proof of that.

Local bus fleet's in Carroll County Maryland had some problems this week and the temp was only down to around +7 or +8 degree's F, and on top of that it is even a winter blend fuel. Around Westminster they cut the winter blend fuel with ULSK 1 (ultra low sulfur kerosene #1) instead of ULSD 1.

One thing I think we need to clear up is some of the terms being thrown around.

Pour Point = The pour point of a fuel is typically 5 degrees F above the temperature at which the fuel fails to flow and turns solid (CFPP). This is also the lowest temperature that the fuel will flow sufficiently to be pumped or transferred.

Gel Point / Cold Filter Plug Point (CFPP) = This is the temperature at which the paraffin waxes in the fuel actually turn solid and clump up.

Pour Point Depressant / Anti-Gel = This is a additive you add to your fuel that lowers the pour point. On the microscopic scale wax molecules are long slender molecules. When they reach the gel point they start to align into clumps that evenly align and start to form microscopic sheets of wax crystals. These clumps are to large to pass through fuel filter media and in severe cases can even form solid clumps in fuel lines. A pour depressant modify's the size and shape of the wax crystals and keeps them from combining with one another to form a gel.

Now, everybody's big question. Do I need a pour point depressant in my fuel? No way of telling without testing your fuel to tell what it's CFPP is. If it's been cold where you are and have not had any problems then your fuel supplier is probably adding a healthy dose of pour point depressants and cutting the fuel with enough ULSK 1 or ULSD 1 to lower the CFPP. If like many you have been having problems I suggest buying some pour point depressant (anti-gel) additive and having it on hand to add to your fuel BEFORE it gel's up. Just keep a eye on the weather reports and when you see a cold spell coming treat your fuel.

 

[Iowachild]

That may be very true but not all ULSD that is hitting the pumps has a pour point that low. If the fuel you are talking about comes from PA crude it is naturally lower in paraffin's and higher in aromatic's which lead to lower pour points. However, not everything that is being dispensed is that good. The horrible problems some people are having with temps in above 0 degree F. weather this last weak is proof of that.

Local bus fleet's in Carroll County Maryland had some problems this week and the temp was only down to around +7 or +8 degree's F, and on top of that it is even a winter blend fuel. Around Westminster they cut the winter blend fuel with ULSK 1 (ultra low sulfur kerosene #1) instead of ULSD 1.

One thing I think we need to clear up is some of the terms being thrown around.

Pour Point = The pour point of a fuel is typically 5 degrees F above the temperature at which the fuel fails to flow and turns solid (CFPP). This is also the lowest temperature that the fuel will flow sufficiently to be pumped or transferred.

Gel Point / Cold Filter Plug Point (CFPP) = This is the temperature at which the paraffin waxes in the fuel actually turn solid and clump up.

Pour Point Depressant / Anti-Gel = This is a additive you add to your fuel that lowers the pour point. On the microscopic scale wax molecules are long slender molecules. When they reach the gel point they start to align into clumps that evenly align and start to form microscopic sheets of wax crystals. These clumps are to large to pass through fuel filter media and in severe cases can even form solid clumps in fuel lines. A pour depressant modify's the size and shape of the wax crystals and keeps them from combining with one another to form a gel.

Now, everybody's big question. Do I need a pour point depressant in my fuel? No way of telling without testing your fuel to tell what it's CFPP is. If it's been cold where you are and have not had any problems then your fuel supplier is probably adding a healthy dose of pour point depressants and cutting the fuel with enough ULSK 1 or ULSD 1 to lower the CFPP. If like many you have been having problems I suggest buying some pour point depressant (anti-gel) additive and having it on hand to add to your fuel BEFORE it gel's up. Just keep a eye on the weather reports and when you see a cold spell coming treat your fuel.

All our crude is Canadian!

 

[moeh1]

They had a news interview with one of the school's head mechanic, cut to a shot of Baldwin filters (one new and one clogged, with a big bottle of Power Service next to them). At least some of these guys know what they should do, I think the whole area got some lousy fuel.

 

[MikeD74T]

Two weeks ago driving my Duramax to work at 1:30 PM it lost power & stopped. Outside temp was 7 degrees. I changed the filter but the hand pump would not prime the new filter. No ice in filter & fuel drained from it. Had truck towed to my home, put in unheated garage, got a ride to work. Next morning 14 degrees hand pump primed the filter & it drove normally. Have owned the truck for 5 years & it's seen - 45 degrees without any gelling or other fuel problems. Never found a conclusive reason for the fuel line obstruction. Fuel in the tank was from a high volume station that I use 90+% of the time, ultra low sulfur. MikeD74T

 

[dholly]

One thing I think we need to clear up is some of the terms being thrown around.

Pour Point = The pour point of a fuel is typically 5 degrees F above the temperature at which the fuel fails to flow and turns solid (CFPP). This is also the lowest temperature that the fuel will flow sufficiently to be pumped or transferred.

Gel Point / Cold Filter Plug Point (CFPP) = This is the temperature at which the paraffin waxes in the fuel actually turn solid and clump up.

Thank you for explaining the difference, and advising end-users to take both with a grain of salt. Not that it matters much... when I asked the managers of the local stations I frequent for the pour and gel point of their winter blend, they -all- said "Gee, I don't know, why would you want to know that?". They've obviously never owned a diesel powered vehicle. I just add PS when temps fall into the teens. I'd rather leave a little money on the table than deal with an incapacitated vehicle in freezing weather.

An interesting snippet from one of the local news experts:

Diesel fuel in school buses jelled, clogging fuel filters. The problem stems from the use of a state-mandated low-sulfur diesel fuel additive. Some districts buy fuel with the additive included while others buy fuel without the additive and add it themselves.

The mandate is new this school year and Monday's extremely cold weather was the first time the additive was needed, Proukou said.

The problem in Spencerport occurred because crews there added the fuel additive to fuel already containing the additive.

The incorrect balance in the fuel caused the fuel to jell.

Apparently, you can have TOO MUCH anti-gel additive!?

 

[DieselPower]

I'm not to sure about the "have to much anti-gel additive" part. I guess it depends on the brand you are using. I know the one I sell you can continue to add it in higher concentrations.

Directly from the tech sheet:

When treated at a recommended rate of 1 gallon of Diesel Fuel Pour Depressant to 1,000 gallons of fuel a 20 degree F. drop in pour point can be expected on a fuel that has not been previously treated. If this 1,000 gallons are treated with another 1 gallon of additive it drops it a additional 8-10 degrees F. Subsequent treatments will lower the pour point less, which illustrates the fact that wax crystals can only be modified a certain amount, regardless of the type of treatment.

Iowachild - Do you know what grade of crude you guy's get from Canada?

 

[Champy]

So can someone clarify a point.........Can you add too much anti-gel?

1 gal of depressant to treat 1000ga of fuel is about only 1 oz to treat my whole 8 gal tank. Is it a problem to add 2 oz....how exact must the measurement be? How much is too much?

Thanks