The Dawn of ULSD: Does your preferred additive address o-ring shrinkage?

Guys, I thought it might be best to start a fresh thread to identify which mfr has elected to address the seal shrinkage issue head-on and who has not. So, I contacted the ever-helpful Brian Wilson at PowerService and his response is below concerning ULSD, seal shrinkage and what they have done to address it.

I have also contacted Dave G at Red Line for his response. Will post when/if I have his permission to do so.


Would it be acceptable to y'all if we stay on-topic and try to keep this thread streamlined with pertinent info only

I am NOT contacting anyone else. It would be real nice to see a few others getting involved by dropping a quikee email to a fuel additive supplier or two 'til we have the mainstream producers covered.

I think knowing the responses may help head off expensive repairs. ULSD could turn into a political hot potato.

Thanks.

Brian, we're just starting to get all sorts of unsavory reports concerning big diesel fuel leaks ( http://forums.tdiclub.com/showthread.php?t=147828 ) on older cars. Do any of the PS products control gasket/o-ring shrinkage? I was hoping this leaking issue was not going to be widespread but that appears to be wishful thinking on my part.

: ((


Thanks,
DD

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DD,

When they reduced the sulfur level of the fuel the EPA also mandated that the aromatic content of ULSD (Ultra Low Sulfur Diesel) Fuel also be lowered. This can affect seals in older equipment (on road and off-road). The older equipment has seals that need aromatics to keep them from shrinking. In 1993 when we first went from high sulfur (not greater than 5,000 parts per million sulfur) down to 500ppm sulfur the aromatics where also reduced and many fuel pumps and seals started leaking. The fix was to replace the seals with seals that did not need aromatics to keep them from shrinking.

With the introduction of ULSD it has been stated by the (so called experts) experts that this should not be a problem this time around or if it is a problem it would be very limited. As we start putting this new fuel into our vehicles we will find out how much of a problem it will really be since no one knows for sure.

Our products, Diesel Kleen and Diesel Fuel Supplement are not silver bullets, however they will help to prevent a lot of problems with the new fuels. The EMA (Engine Manufacturers Association) says that ULSD will cause many problems that can be overcome with the use of a good additive. For example the EMA says that you will need to use a detergent to keep carbon deposits from forming in the injectors caused by the new fuels. They also say that lubricity should be higher, that a fuel stability package should be used and that the Cetane Number should also be higher. Diesel Fuel Supplement and Diesel Kleen will help with these problems and will also lessen the problem of leaking seals. The EMA also says that microbial contamination will be greater.

You should use Diesel Kleen in the non-winter months and Diesel Fuel Supplement in the winter months.

If you have any other questions or concerns please let me know. By the way, I have 2 older tractors and a 1998 Dodge truck. It is not that I am concerned but the thought of having to pay to fix a problem if it arises makes me worry about these new fuels. I will also be keeping my fingers crossed that the experts are correct and only minor problems will arise with the use of the new fuels.

Best regards,

Brian Wilson
Technical Advisor
Compliance Coordinator
(800)643-9089
bwilson@powerservice.com

Power Service Products, Inc.





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Brian, as always, I appreciate you taking the time to offer detailed replies. I'd like to be able to share with the group assuming I have your permission to do so.

Can you expand upon this a bit (without revealing any trade secrets):


"Diesel Fuel Supplement and Diesel Kleen will help with these problems and will also lessen the problem of leaking seals."


I am certain the guys are going to want to know the specifics. Thanks.

DD

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DD,

It is difficult to tell you in detail what we have done to our products to lessen the problems of leaking seals without giving you chemical information. We took steps over 2 years ago to come up with a product that would work with the new ULSD fuels that are now hitting the market. There are certain type chemicals that will dry seals or have no positive effect on seals. There are others that have a positive effect on seals. We have formulated our products to have positive effects on all of the bad effects of ULSD fuel and we were probably the first product on the market that meets the new ULSD requirements for diesel fuel additives. Having said that we know that there are some products on the market that are nothing but alcohol or mostly Butyl Cellosolve which would meet the ULSD mandates but are not by themselves much of a additive package and certainly not a complete additive as Diesel Fuel Supplement or Diesel Kleen.

The current wisdom on seals is that equipment that is 10 years or newer is not expected to have any major seal problems. Current seals last about 15 years without much trouble (some last longer than others and it is hard to say exactly why) so equipment that is 10 years old and less than 15 years old will start to see some seal leakage as seals age and lose elasticity. The older equipment 15 to 20 years ago relied on the fuel having aromatic content around 35% or higher and was based on high sulfur fuels. These seals had a lot of problems when we switched to Low Sulfur Fuels in 1993. If you have equipment (on road or off-road and it was manufactured in 1994 then you are getting close to the expected life of the seals and if you develop leaks it may be related more to the age of the seals rather than the new fuels. I had to replace my fuel pump on my 20 year old tractor two months ago. The seals around the pump and the pump itself finally gave up. If I was using ULSD I would have a tendency to suspect the fuel. Since I know that ULSD was never used in the tractor I think is was old age that did them in. This makes if difficult to really know what is wearing out due to age and what is failing due to the new fuels.

The EMA (Engine Manufacturers Association) which represents the interest of all diesel engine manufacturers put out a statement on the new ULSD fuels which I briefly outlined in my last response. Their outline on the new ULSD fuels makes it clear that if you want to keep your equipment running as intended you will have to use an additive. No additive on the market is a silver bullet that will cure all problems. Our additives are as close as you will come to that.

This is as about all I can say without getting into Trade Secrets or Chemical makeup. I am sorry that I could not be of more help with your question and I am sure that this will be somewhat of a disappointment.

Let me know if I can be of any other help.

Best regards,








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Brian, thanks. I accept your assurances that PowerService has made efforts to address this seal problem without knowing the specifics. I have to believe that at least a few of the additive manufacturers will have given it some consideration. It would be irresponsible otherwise.

Is it OK to share your comments and thoughts on this?

DD

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DD,


It is not a problem for me if you want to share this info.


You may be surprised about the irresponsible additive manufacturers. Most of them were taken by surprise, did not know they had to put a mandated EPA label on their bottles saying that they were not compliant and most of their products are not compliant with the new ULSD requirements as of this writing. The only thing that surprised us is that EPA mandated the label on all bottles regardless of when it was made (this year or ten years ago).


Hope to hear from you later.



Brian

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Biodiesel just seems to be the perfect additive for ULSD. It would take care of any lubricity issue and it would probably counter any rubber shrinkage too. But very few stations around the country have biodiesel, unless you're in Minnesota. Part of the problem is putting rubber in injection pumps in the first place and I think that's just sloppiness on the part of the auto manufacturers and their contractors. A good quality injection pump has no rubber, like the one in my 240D. One thing that I find comforting is that the Europeans have been dealing with ULSD for quite some time and any rubber in a recently made TDI should be compatible with ULSD.

DD-
Thanks for starting this thread. Hopefully we can keep it on topic.

If they changed the design of the seals in response to the transition to LSD back in the mid-90's to be less affected by aromatic content, then it seems odd we are still having these problems.

If there are effective additives to counter this, then why wouldn't they be added (as the lubrication additive is supposed to be) at the tankers before delivery to retail pumps? Do the additives threaten the 15ppm mandate? Can the additives actually prevent the shrinkage? (Brian doesn't sound definitive, IMO.) Would we be willing to pay extra at the pump to have these added? I would if they were necessary and effective.

As Brian points out- the service life for many of the older vehicles' seals is probably reaching the limits. Are the changes in ULSD formulation contributing to shortened life? Maybe. Would the seals need to be changed in the future anyway? Sounds to me like they would.

It sounds like we only know of that one place in Portland that does rebuilds. I remember threads where folks here replaced IP seals themselves. If this is accurate, I hope someone who has done this successfully will make a nice HOW-TO to add to Wingnuts list.

As of now, I see all this as the price of progress. (but I can afford to be objective at this point )

tditom said:

...
As Brian points out- the service life for many of the older vehicles' seals is probably reaching the limits. Are the changes in ULSD formulation contributing to shortened life? Maybe. Would the seals need to be changed in the future anyway? Sounds to me like they would.
...

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This doesn't explain our batch of TDI's with leaking fuel pumps, as it's one 2001 and 3 2002's. They certainly wouldn't be at the end of their useful life. However, most if not all of us were using Biodiesel and switched to regular diesel (which we can presume is becoming closer to ULSD every tankful, though not marked as it yet).

In the past, we've switched back and forth with no problems. However, would the entrance of ULSD cause switching from Bio to ULSD to be an issue for our IPs?

My understanding was that BIo makes the seals swell and LSD makes them shrink. Does ULSD make them shrink more than LSD? Still trying to figure out why all our cars are leaking at once...

Oh, and refilling the cars with Biodiesel seems to cure the leaking within a 100 miles or so.

Biodiesel contains practically zero aromatics and will not prevent any seal shrinkage. In fact, it causes seal shrinkage in older (pre '94) gaskets in concentrations above B20. This is not due to the age of the gaskets but because shrink-susceptible materials such as butyl-N were commonly used in pre 1994 vehicles.



Correction: Although BD contains no aromatics (only methyl or ethyl esters) I think the leakage problem in older vehicles is caused by excessive swelling, not shrinking (sorry.. it's been a while since I've read about this subject). Could there be an optimum BD/ULSD blend to run in older vehicles to balance the shrinkage/swelling problem?

Fewer aromatics--not necessarily

I would question the statement that ULSD automatically means fewer aromatics. Indeed, more severe hydrotreating will reduce aromatics, but if there's a corresponding increase in octane, blenders may add more light cycle oil to the diesel, bringing the cetane back down and maintaining a higher aromatic content. This is very dependent on refinery configuration, feedstocks, etc.

You can be sure that diesel from major suppliers will meet all the specs, cetane, lubricity, sulfur, etc., but there are usually multiple paths to meet them, and the blenders will choose the less costly path that will still allow them to meet specs.

OkiTDI

Drewser said:

This doesn't explain our batch of TDI's with leaking fuel pumps, as it's one 2001 and 3 2002's. They certainly wouldn't be at the end of their useful life. However, most if not all of us were using Biodiesel and switched to regular diesel (which we can presume is becoming closer to ULSD every tankful, though not marked as it yet).
I agree- cars of that vintage shouldn't be developing leaks because of old age.

In the past, we've switched back and forth with no problems. However, would the entrance of ULSD cause switching from Bio to ULSD to be an issue for our IPs?
Doesn't seem like it would, but the anecdotal evidence seems to contradict this.

My understanding was that BIo makes the seals swell and LSD makes them shrink. Does ULSD make them shrink more than LSD? Still trying to figure out why all our cars are leaking at once...
You got this backwards. LSD has high aromatic content. BD has low content. The aromatics in the LSD can cause the seal material to swell (after long term use- supposedly). From here it seems that either of the following occur: #1. This pushes the seal points apart slightly. When a low aromatic is then used, the seals shrink slightly- leaving the seal points pushed apart.
#2 When a low aromatic is subsequently used, the seal material actually does shrink down so it is smaller than originally designed.
In either scenario, the smaller seal leaves a gap between the parts.


Oh, and refilling the cars with Biodiesel seems to cure the leaking within a 100 miles or so.
This is what I find really odd. If both BD and ULSD are low aromatics, then why would the seals swell up enough to stop the leak? Please keep us updated on if this holds out.

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What BD% are you running? Is the D2 portion of it most likely LSD?

OkiTdi said:

I would question the statement that ULSD automatically means fewer aromatics. Indeed, more severe hydrotreating will reduce aromatics, but if there's a corresponding increase in octane, blenders may add more light cycle oil to the diesel, bringing the cetane back down and maintaining a higher aromatic content. This is very dependent on refinery configuration, feedstocks, etc.

You can be sure that diesel from major suppliers will meet all the specs, cetane, lubricity, sulfur, etc., but there are usually multiple paths to meet them, and the blenders will choose the less costly path that will still allow them to meet specs.

OkiTDI

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I agree diesel blenders will gladly dilute with cheaper products to maximize profit, but how much minimally/non hydrotreated LCO can they add back and still meet a 15 ppm Sulfur spec? The average cetane number from LSD to ULSD is expected to go from 42.5 to 47! WooHoo!

tditom said:

What BD% are you running? Is the D2 portion of it most likely LSD?

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My understanding is BD causes swelling not because of aromatics but because it is an AMAZING solvent and reacts (attempts to dissolve) with the older gasket materials in the same way aromatics do.

And yes, it is a shrinkage issue. Higher aromatic levels/low analine points cause many seal materials to expand. When a lower aromatic level fuel is introduced, the seals shrink with resulting leakage. When the seals were replaced in engines with the first go round from high to low sulfur, it was with the same seals. The seals just need to "set" at the new aromatic/analine level and business as usual.

And yes, Primrose fuel additives, to include 405C, 409, 2003, and 4033, now include additional additization to raise the analine point of the treated fuel to help minimize seal shrinkage. However, there may be cases where the shrinkage may have already taken place; the additives will not raise the dead....
George Morrison, STLE CLS

George, thanks for your addition concerning the Primrose product line and the clarification on seals not being able to expand again.

One other question: Can #405 be added to your list? I see you have listed the concentrated version (#405C).

Thanks.

tditom said:

If they changed the design of the seals in response to the transition to LSD back in the mid-90's to be less affected by aromatic content, then it seems odd we are still having these problems.

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I think the materials utilized post-1993 are less sensitive to this swelling/shrinkage issue. However, they do NOT appear to be completely immune as we're seeing...

I will try to contact Bosch and ask what steps they have taken to deal with the changes in ULSD. BTW- does the tandem pump used on PD's need to be addressed here, or only IP vehicles?

Georgeseq said:

And yes, it is a shrinkage issue. Higher aromatic levels/low analine points cause many seal materials to expand. When a lower aromatic level fuel is introduced, the seals shrink with resulting leakage. When the seals were replaced in engines with the first go round from high to low sulfur, it was with the same seals. The seals just need to "set" at the new aromatic/analine level and business as usual.

And yes, Primrose fuel additives, to include 405C, 409, 2003, and 4033, now include additional additization to raise the analine point of the treated fuel to help minimize seal shrinkage. However, there may be cases where the shrinkage may have already taken place; the additives will not raise the dead....
George Morrison, STLE CLS

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Wouldn't they want to lower the Aniline Point? Lower Aniline Point = more aromatics = more similar to previous fuels = less shrinkage

I can remember when the first synthetic oil first came on the market there was a leakage issue, saying that the synthetic would not swell seals and permit leaks. If I can remember the conventional swelled seals slightly allowing a tighter seal, and the synthetics lacked the swelling effect. The end result was that the synthetics did not shrink the seals, just allowed them to return to their original size, and after being swelled which allowed increased wear, allowed the leakage. I was told at the time that the problem was running conventional then switching, and it was worse with higher milage vehicles. There was no problem if the switch was done early in the vehicles life. The refiners eventually came up with a fix, and the synthetics now do not have this drawback. This could be the same problem we are facing with ULSD. The loss of aromatics is caused by the hydrotreating to remove the sulphur, not mandated in the ULSD spec, just a byproduct of the removal process, as far as I know. This post is related to the ULSD post, and with knowledge of the ULSD will allow us to be sure the fuel will not damage components. An ounce of prevention is worth a pound of cure. How many bottles of additive can you purchase with the cost of pump replacement? I'm not saying to run out and buy any additives, just wanting to know the facts and be able to take preventive measures based on the facts.

tditom said:

What BD% are you running? Is the D2 portion of it most likely LSD?

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I used D2 up to around 60k miles full time. Then I switched to Bio, and for about 4k miles I would go back and forth. Now I'm at around 90k miles and I've been running B100 for the last 26k miles. Switched back to Dino for a tank and noticed the leak, so switched back to Bio and the leak seems to have mostly gone away.

Makes sense that Bio would have similiar properties to ULSD. However, this is what I haven't figured out yet:

1) Why does switching back to B100 stop the leak (and was proven in 2 other cars in our area as well)?

2) Why is this just happening now, and to so many cars at once?

The only variables that have changed are age of car, time running B100, and the introduction of ULSD into the fuel system (even if it's not officially labeled yet). Seems the cause would have to be one of these or a combination...I just haven't figured out the coorelation yet...

The higher the analine point, the less reactivity with seals/hoses.. i.e. a good hydraulic oil has an analine point of, say, 220, while alcohol has an anline point of 77...... Sooo, yes, we want an elevation of analine point for the fuel to minimize shrinkage...

Re: additization.. Some fuel additives provide significant fuel mileage increases which more than offset the cost of the additives, plus eliminate free water, rust, provide increasede lubricity and aggressive detergency to keep the fuel system optimally clean, including injectors.. So, the use of certain fuel additives can be a total win/win situation..
George Morrison, STLE CLS

Has anyone contacted Parker-Hannefin, a huge maker of anything that needs seals to see what they say?

It's my opinion that seals have a MTBF of either cycles of heat/cool or time before they go south and leak. Every time you heat a rubber seal up, you drive out some of the solvents or product that keep it elastic. Drive the elsaticity out of it, and it hardens, cracks, or loses it's elasticity and eventually fails.

Additives are a good idea and sound like preventative maintenance, but when the seals go, they go. Once they are leaking, you cant turn back time or the number of cycles. You've then reached the point where the project needs surgery to stop the leaking and bleeding of fuel, not a bandaid like additive.

Georgesq has presented the most logical unbiased posts in this string.

Time to buy and install a seal kit if your TDI gets the runs.

Georgeseq said:

The higher the analine point, the less reactivity with seals/hoses.. i.e. a good hydraulic oil has an analine point of, say, 220, while alcohol has an anline point of 77...... Sooo, yes, we want an elevation of analine point for the fuel to minimize shrinkage...

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Aniline Point (FYI spelled "ani" not "ana") is a direct measure of solvency and is commonly used in the refining industry to predict the aromatic concentration or even cetane number of a distillate. While you are correct that a higher Aniline Point means less rectivity with seals, it would minimize SWELLING not shrinking.

It would actually maximize shrinking because the "shrinking" of seals occurs when a seal previously exposed to aromatics in an oil (or fuel with a lower Aniline Point such as LSD) has caused it to swell slightly and then is exposed to an oil with fewer aromatics (or fuel with a higher Aniline Point such as ULSD) the swollen seal tries to return to its normal size or "shrink".

A higher Aniline Point fuel would be better if was the first fuel a seal was exposed to (because it wouldn't swell in the first place) but exposing an already swollen seal to a higher Aniline Point fuel would actually cause it to "shrink" more.

So do we have any idea where LSD, ULSD, and Bio fall on this Aniline scale? Just curious...

I just checked the place where I got my Stanadyne from (www.mwfi.com) and they state that Stanadyne is rebottling for compliance with ULSD.

Drewser said:

So do we have any idea where LSD, ULSD, and Bio fall on this Aniline scale? Just curious...

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Soy based BD's Aniline Point is around 60 ºC (140 ºF) and LSD is around 70 ºC (160 ºF). I was unable to find an Aniline Point spec for ULSD but would expect is to be even higher than LSD.

So Soy based BD is the lowest and ULSD is the highest of the 3? This could explain why the issue is suddenly occuring...

Oh, and I looked today and mine appears to still be leaking, though not as bad. It's damp down below the pump, but not on the back side any more.

Drewser said:

So Soy based BD is the lowest and ULSD is the highest of the 3? This could explain why the issue is suddenly occuring...

Oh, and I looked today and mine appears to still be leaking, though not as bad. It's damp down below the pump, but not on the back side any more.

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Yes... and the lower Aniline Point of biodiesel would suggest more swelling and the higher Aniline Point of D2 (especially ULSD) would suggest less swelling (or more shrinkage... depending on how you want to look at it). It is also worth mentioning that your seals will only swell and shrink so many times before they lose their structural integrity.

Although with a 2002MY I wouldn't think the swelling and shrinking would be that severe in your seals... but it sounds like it's significant enough to cause leakage. I would recommend picking a BD concentration and sticking with it... or at least not running straight ULSD until your seals are changed.

So are there seals that are immune to this? Such as Viton seals or the like? Apparently the Portland shop says when they rebuild your pump you can run whatever you want with the new seals...

Drewser said:

So are there seals that are immune to this? Such as Viton seals or the like? Apparently the Portland shop says when they rebuild your pump you can run whatever you want with the new seals...

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Yes there are seals that are immune to it. Teflon seals like PTFE or PFA would definitely work but are probably too expensive to use.

Here are a couple of helpful links on seal material selection:

http://www.me.iastate.edu/biodiesel/Pages/biodiesel22.html
www.biodiesel.org/pdf_files/fuelfactsheets/Materials_Compatibility.pdf

I have written the following to Stanadyne. Their reply will be posted.
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There is a lively discussion taking place on the TDICLUB.COM about the need for improved additives with the introduction of Ultra Low Sulfur Diesel.

At issue is what additive is superior for the prevention of seal shrinkage when ULSD is used.

Could you please advise what is Stanadyne's position on the issue? Also, is there a reformulation of Performance, Lubricity or both in the works? If so, what is the expected release date.

Please note that the questions go to the preservation of our engines, not compliance with EPA requirements.

Thank you.

Jack McAdams

PS: I request to share your response with the members of the TDICLUB if I may.

JM

Dave G @ RedLine sez:

Dave, we're getting a lot of 1st hand reports about injector pumps leaking, some of them are severe. Many folks are reporting the rubber fuel return lines are leaking, too. This issue appears to have a direct correlation to the arrival of ULSD in parts of the US.

Can you tell me, without revealing any proprietary info, if Red Line has done anything to address this seal/o-ring shrinkage issue in the make-up of DFC and your other diesel fuel additives?


Thanks


DD


Here's one on-going discussion concerning MBz and VW diesels: http://forums.tdiclub.com/showthread.php?t=147828

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DD,

If the issue is seal shrinkage then it would be more economical to just change the seal material, it would require so much seal swell used on a continuous basis to not be cost effective.

It is possible the pump leakage issues experienced is due to a decrease in lubricity, this has been addressed in the Diesel Fuel Catalyst and 85+.

Regards,
Dave
Red Line Oil



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Dave, thanks for your reply. A lot of folks use RedLine DFC. Is it OK to share your comments?​

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DD,

Oh sure, you are welcome to share them, hope they are helpful.

The chemist has been using ULSD in is TDI Beetle basically from new without any issues.

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Guys you are wasting your time, TDI's are already designed to run on ULSD...Ever hear of German cars with leaking fuel systems due to the fact they have been running ULSD for about the last decade?

If you have an old Cummins or some other diesel engine you may have a slight concern HOWEVER any TDI engine already came with fuel systems set up to run ULSD.

I woke up today and parked outside was a brand new 2007 Audi A8 TDI with the 325hp twin turbo...oops forgot to say I am in Germany!

DB

I was just going to ask if VW was using different seals in America than they are in Europe.