Best diesel lubricity formula

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Had old school Detroit 8v92's in my Hatteras. The design uses a lot of fuel to cool and lube the injectors (Ski can chime in with specifics). Detroit's updated engine manuals specifically discouraged additives, and their fuel specs had a maximum sulfur rating, no minimum. As far as they were concerned the less sulfur content the better.

As a newbie, I used a well spoken of additive for a little while (Pri-D). One day my very experienced mechanic was on board and saw the jug. He said "gimme fifty bucks" and I said "for what?" ... "to stand here and look at that jug for a minute" "Huh ?" "It will do as much to improve your engines as that stuff does".
 
He buys Rotella dino oil in 55 gallon drums and uses Blackstone labs for change interval data points, by the type of equipment. I know he uses Fleetguard, Wix and some Baldwin filters because I see them on the shelves.

Yes- Rotella dino by the drum. Same oil used in a factory that runs 8 diesels in a rack mount I used to visit many years back. They were used to provide best DC power to a larger electroplating line that ran 24/7/365. There was always at least 5 running but many times 6 as the other two were either being serviced or on standby. They never used any additives either for the fuel or lube oil and had a couple of years on most of the engines on the line. The plan was to bring them down for engine rebuilds when the oil usage approached 2% of the fuel use but they had not reached that point when last I was there.
 
Yes- Rotella dino by the drum. Same oil used in a factory that runs 8 diesels in a rack mount I used to visit many years back. They were used to provide best DC power to a larger electroplating line that ran 24/7/365. There was always at least 5 running but many times 6 as the other two were either being serviced or on standby. They never used any additives either for the fuel or lube oil and had a couple of years on most of the engines on the line. The plan was to bring them down for engine rebuilds when the oil usage approached 2% of the fuel use but they had not reached that point when last I was there.

Smitty

That pretty well mirrors my dirt moving and genset experience. The incoming fuel deliveries were continually sampled and tested for a variety of things with water being monitored by a close eye.

Not unusual to send samples to a test lab to insure engine warranty guidelines were being adhered to including lubricity. Some big mining operations get close to 1 million gallons per month with fuel suppliers not wanting to screw that contact up..
 
For folks that worry a quart of 2cycle outboard lube oil every hundred gallons does a great job if the injectors need help.
 
For folks that worry a quart of 2cycle outboard lube oil every hundred gallons does a great job if the injectors need help.

Detroit specifically warned against doing that for their engines at least.
 
He buys Rotella dino oil in 55 gallon drums and uses Blackstone labs for change interval data points, by the type of equipment. I know he uses Fleetguard, Wix and some Baldwin filters because I see them on the shelves.

Thank you. In other words, he changes oil when the test says it's time to change, not after a fixed number of hours as many boaters do, although not I. I use synthetic oil in my Chevy Duramax and in my Ford Lehman 120. I use it in the Lehman not because I believe it will extend the useful life of the engine, but because I can use extended oil change intervals, with testing. Is that a waste of money? I don't think so cuz oil changes occur far less frequently. Then there is the added convenience of not having to change oil as often an getting rid of it while cruising. Filters changed along the way, of course. testing includes soot load and when that gets beyond the standard, the oil goes. Same for TBN. Am I right? Am I wrong? I don't know. It's what I do. If others do differently, good on you.

,
 
Thank you. In other words, he changes oil when the test says it's time to change, not after a fixed number of hours as many boaters do, although not I. I use synthetic oil in my Chevy Duramax and in my Ford Lehman 120. I use it in the Lehman not because I believe it will extend the useful life of the engine, but because I can use extended oil change intervals, with testing. Is that a waste of money? I don't think so cuz oil changes occur far less frequently. Then there is the added convenience of not having to change oil as often an getting rid of it while cruising. Filters changed along the way, of course. testing includes soot load and when that gets beyond the standard, the oil goes. Same for TBN. Am I right? Am I wrong? I don't know. It's what I do. If others do differently, good on you.

Could you advise what you typical change interval is with synthetics?
 
I have about 20 diesel engines on the farm. For the most part they seem to run almost forever. The failures that occur have not been related to lub issues. I use Rotella T in everything. I don't use any additives.

The last diesel boat I owned had a six cylinder Mercedes which had six thousand hours on the engine when I sold the boat. The engine was running well at that time. There was some loss of compression and if I was going to keep the boat I would have rebuilt the engine at some point.

The most important issue for me was not how long it would last but when it was most likely to fail. To that end I did regular oil analysis. I did regular compression test and changed injectors and fuel pumps before they failed. I also used Rotella T in that engine most of the time.

While it may be true that modern chemical additives could prolong engine life, I think that would be difficult to predict for any given engine. There are just too many factors involved. No testing is likely to replicate my specific set of conditions.

My experience indicates the best way to keep a diesel running is proper maintenance and very frequent use. I start my boat and run it under load every day I possibly can.

One hears the statement " we ran the engine 24/7 for more than 10,000 hours". That same engine run occasionally would likely fail in half the time.

Most boats die from sitting at the dock doing nothing.
 
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As we talk about snake oil - I have Ford 120's in my 1977 Grand Banks. 3,600 hours. Run well but a little smoke. I have been told that using Stiction Eliminator could help clear that up? (also told there is a stiction additive for fuel that would help the injectors and pump) anyone have any experance or thoughts?

You can buy into the "all additives are stupid" wagon but I believe there are some additives that are useful. May be helpful for your old FL's.

1.
Power Punch may be what you refer to as "stiction eliminator" but those additives that are quite thick but thicken the oil minimally would probably help your compression.

2.
SeaFoam will free up stuck or semi-stuck rings. That will increase compression possibly a lot. It's best if you can apply it on the side of the piston by the cylinder wall. But most diesels have dished pistons so that may be dificult. One could prehaps put a few ounces of SeaFoam anywhere in the combustion chamber and crank the engine only 3 or 4 revolutions to throw the SeaFoam out onto the cylinder walls. Then let it sit for a day or two to penetrate all the rings. Several days may be better.

Just an idea. I haven't used either product or proceedure in this way. Years ago I used the Power Punch type oils and they worked as advertised. I have used SeaFoam many times and it will even free up seized engines. If you use more than very small quantities (like in the fuel) changing oil soon after may be a good idea. I'd be interested in constructive - or + comments about either product as there may be downsides I'm not aware of.
 
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The feedback on this subject I find most useful is from people who have heavy machinery operations whether its Marine, Industrial, or on a farm. This same type of information is why I stopped using Stenadyne about a year ago. Regarding Biocide, I still use it - Biobor JF to be specific. Snake oil? Possibly, but it still makes sense to me for a marine environment where fuel is sitting in a tank for longer of periods of time.
 
Three things
1 Does lubricity have anything to do with oil additives? Can't see that it does.
2. Big fleet oil analysis I've been involved with had less to with oil change intervals and more to do with establishing timelines for wear and internal rebuilds. In many cases, after tens of thousands of hours or years of monitoring fluids, tear downs were scheduled before failure.
3. Your engine will be well treated if you go by the book in virtually all respects. Most marine engines will outlive and survive owner engineering, spawning all sorts of apparent success stories.
 
Food for thought. I've run all my land based stuff hard. Towing, racing you name it. Never had a failure. https://tinyurl.com/y882r2lb This is what I feed our Cummins. The new formulation out this fall is backward compatible to pre 2007 engines and surpasses even this noted product performance.
 
Food for thought. I've run all my land based stuff hard. Towing, racing you name it. Never had a failure. https://tinyurl.com/y882r2lb This is what I feed our Cummins. The new formulation out this fall is backward compatible to pre 2007 engines and surpasses even this noted product performance.

What is cost for one gallon of Amsoil suitable for Cummins diesel?
 
In an earlier post, I quoted what Chevron says on this subject:

“Aftermarket Additives

It would be convenient for the user if a finished diesel fuel could satisfy all of his or her requirements without the use of supplemental additives. Although this is usually the case, some users require additional additives because the low-temperature conditions in their region are more severe than those for which the fuel was designed or because of other special circumstances. Other users feel that they will benefit from using a diesel fuel with enhanced properties compared to using regular diesel. Finally, there are users who regard the cost of an additive as cheap insurance for their large investment in equipment.

A large number of aftermarket additive products are available to meet these real or perceived needs. Some are aggressively marketed with testimonials and bold performance claims that seem “too good to be true.” As with any purchase, it is wise to remember the advice, caveat emptor, “let the buyer beware.”

It may be helpful to regard additives as medicine for fuel. Like medicine, they should be prescribed by an expert who has made an effort to diagnose the problem, as well as the underlying causes. Additives should be used in accordance with the recommendations of the engine manufacturer, and the instructions of the additive supplier. Sometimes, indiscriminant use of additives can do more harm than good because of unexpected interactions.”

https://www.chevron.com/-/media/chevron/operations/documents/diesel-fuel-tech-review.pdf
Page 95.

Jim
 
I had a fuel pump cam fail on a 3208 a year and a half ago. Needed to replace pump, all injectors, all lines and adaptors. That was expensive. So I looked into lubricity in detail. It's the process of removing sulfur that reduces fuel lubricity. Current specs barely meet most diesel engine requirements for lubricity, including the specific cat fuel specs I found.

I have had no luck in getting fuel specs from several of the suppliers in the s fl area. The two additives that stood out are optilube lubricity formula and stanadyne lubricity formula, not their general additives. From both suppliers test results are available for wear tests. They do show significant improvement in the standard astm wear tests. Optilube showed a nearly 50 percent reduction iirc.

My biggest worry is we spend a lot of time in the Bahamas and I have no confidence in their fuel meeting specs. And the random fuel tests I found had results with some fuels barely or not actually meeting specs. So if you can't use a reliable fuel supplier that can provide fuel specs and have an older mechanical injection system it may make sense to use a lubricity additive. My cat dealer said they had an increase in mechanical injection pump and injector failures and had no problem with my using a lubricity specific additive
 
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Current specs barely meet most diesel engine requirements for lubricity, including the specific cat fuel specs I found.


Can you provide a reference for this statement?

Jim
 
I had a fuel pump cam fail on a 3208 a year and a half ago. Needed to replace pump, all injectors, all lines and adaptors. That was expensive. So I looked into lubricity in detail. It's the process of removing sulfur that reduces fuel lubricity. Current specs barely meet most diesel engine requirements for lubricity, including the specific cat fuel specs I found.

I have had no luck in getting fuel specs from several of the suppliers in the s fl area. The two additives that stood out are optilube lubricity formula and stanadyne lubricity formula, not their general additives. From both suppliers test results are available for wear tests. They do show significant improvement in the standard astm wear tests. Optilube showed a nearly 50 percent reduction iirc.

My biggest worry is we spend a lot of time in the Bahamas and I have no confidence in their fuel meeting specs. And the random fuel tests I found had results with some fuels barely or not actually meeting specs. So if you can't use a reliable fuel supplier that can provide fuel specs and have an older mechanical injection system it may make sense to use a lubricity additive. My cat dealer said they had an increase in mechanical injection pump and injector failures and had no problem with my using a lubricity specific additive
And, that folks, is exactly the problem with today's ULSD. It meets a minimum standard, maybe. I own a Chevy Duramax. I have read reports (albeit unverified) that GM CP3 pumps have an 8% failure rate without the use of a lubricity improver, 1% with. Also, why is it that Valvtec fuels marketed to boaters contain higher levels of lubricity improvers? Snake oil? Hardly.
 
“I own a Chevy Duramax. I have read reports (albeit unverified) that GM CP3 pumps have an 8% failure rate without the use of a lubricity improver, 1% with.”

If this were the case GM would be losing a small fortune in warranty and extended warranty claims.

As a guy who has been in the automobile business for more than 40 years, more than 1/2 of those years with GM, I can promise you that GM would be all over that with factory service bullitans (TSB’S) advising the use of a particular additive of some sort. Believe it or not it is to their advantage to be providing reliable vehicles and if there is a product that will increase reliability they will be recommending it or packinging it and selling it.

I am sure that your dealer sells an additive BUT ask them to see the bullitan where GM recommend’s the use of a particular additive. If you see a bullitan from GM I recommend that you use the additive otherwise save your money.
 
I had a fuel pump cam fail on a 3208 a year and a half ago. Needed to replace pump, all injectors, all lines and adaptors. That was expensive. So I looked into lubricity in detail. It's the process of removing sulfur that reduces fuel lubricity. Current specs barely meet most diesel engine requirements for lubricity, including the specific cat fuel specs I found.

I have had no luck in getting fuel specs from several of the suppliers in the s fl area. The two additives that stood out are optilube lubricity formula and stanadyne lubricity formula, not their general additives. From both suppliers test results are available for wear tests. They do show significant improvement in the standard astm wear tests. Optilube showed a nearly 50 percent reduction iirc.

My biggest worry is we spend a lot of time in the Bahamas and I have no confidence in their fuel meeting specs. And the random fuel tests I found had results with some fuels barely or not actually meeting specs. So if you can't use a reliable fuel supplier that can provide fuel specs and have an older mechanical injection system it may make sense to use a lubricity additive. My cat dealer said they had an increase in mechanical injection pump and injector failures and had no problem with my using a lubricity specific additive

How does presumed lowered lubricity in diesel fuel "prematurely" wear out a 3208 injection pump? See post 20. Are there other possibilities such as water in the fuel or lack of good filtering in the 30 year life of these motors?

My questions aside, 2007 a scuff test study using appropriate lab HFFR equipment was conducted by A. Spicer. As noted in the study, diesel fuel was tested using a variety of Lubricity additives.

This study, as are rebuttals, can be easily found elsewhere on the Internet. The study in summary form is copied and used in the past for marketing purposes by Optilube.

Of note:
1. The study was funded by Optilube
2. The diesel fuel tested was without any refiner added lubricity additives.
3. No diesel was tested as received by the end user - us.
3. The best additive, of the 14 tested, was bio diesel at 2%
4. Not surprisingly Optilube came out second best.
5. Marvel mystery oil, Stanadyne and Valvtech performed poorly and in some cases performed worse than untreated diesel.

But, I've not heard of Optilube worsening an engine, which therein lies its beauty to some.
 
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And, that folks, is exactly the problem with today's ULSD. It meets a minimum standard, maybe. I own a Chevy Duramax. I have read reports (albeit unverified) that GM CP3 pumps have an 8% failure rate without the use of a lubricity improver, 1% with. Also, why is it that Valvtec fuels marketed to boaters contain higher levels of lubricity improvers? Snake oil? Hardly.


That pump suffers from a lower than required fuel flow in many instances - the best way to really solve for the problem is to replace it with a previous series pump - there are many folks who have done just that.
 
How does presumed lowered lubricity in diesel fuel "prematurely" wear out a 3208 injection pump? See post 20. Are there other possibilities such as water in the fuel or lack of good filtering in the 30 year life of these motors?

....

3208 is unique among the larger engines that the entire injection pump including cam, rollers and followers are bathed in the fuel that ultimately gets pumped to injectors. So the cam is sensitive to fuel lubricity. And worse than that any wear products from the cam (hardened steel) get into the injector pump elements and injectors. Never liked that design. Similar situation on the CAV and Bosch VE pump, but for some reason those two seem pretty durable.

Most heavy duty engines lube the injection pump cam with lube oil, not fuel. Not only is this a better lube, but any wear products stay out of the injection pump elements and out of the injectors.

New common rail systems tend to be fuel lubed. In the automotive world these have had some of the problems that the 3208 has. Seen some downright crappy designs there. Lessons not learned there????

I don't have any data on the marine CR units, just a lower population and I am a little out of the loop. On the Cummins Q's, have not heard of many failures.

The 3208 failures have been on the 375, 425 and 435hp units run hard in sportfish and charter ops. Have not seen the problem in trawler units but there is one posted above.
 
I use Stanadyne PF on my CAT 3208 and my NL M843N per recommendation of Bob Senter. Bob is the gentleman responsible for training the NL and Lugger techs as well as offering owner training. He is sometimes referred to by the nickname "Lugger Bob" and is highly respected by many in the marine engine and mechanical systems space. I attended Bob's excellent diesel class as well as the free class for Northern Light owners in 2011 and have used SPF since.



A week ago Bob made a presentation to the CUBAR group and again suggested SPF. When asked about alternative products his response was that he couldn't speak to them as he had no scientific evidence of their performance and he had seen thorough documentation of such evidence re: SPF. He described the research done by an engine manufacturer (and source of base engines for Lugger) who tried to lay warranty related injector performance problems off on the injector supplier they used. The injector supplier indicated they'd specified SPF. The engine manufacturer then started a research process of following the injector supplier's recommendation with the expectation they'd refute the recommendation and then get their claim honored. After extensive analysis the engine manufacturer was not able to assert it's claim. And based on that analysis they started private labeling SPF as an additive they sell/supply to their customers. Thus the evidence of which Bob was referring.



My understanding is a fundamental design component is that large quantities of diesel fuel are pumped through the engine fuel system (substantially more than is used in the ignition process) to lubricate and cool the fuel system components - pumps and injectors. Thus the issues of managing fuel return lines to the tanks and so on. Ultra-low sulfur diesel is contrary to this system design need and thus the benefit of SPF.



I spoke with a Cummins Certified Mechanic in up state NY where we purchased our Nordic Tug. He recommends Stanadyne as a way to keep your injectors working like new.

http://usdieselparts.com/c-1093301-...-warm-weather-blend-diesel-fuel-additive.html
 
Can you provide a reference for this statement?

Jim

Direct from ASTM, the diesel fuel specs in the D975 document call for a maximum HFFR wear scar of 520 microns. The ASTM D975 spec mentions that fuels below 450 micron wear should provide sufficient lubricity. The European standard EN 590 is 460 micron and some engine manufacturers and the Engine Manufacturers Assc. call for 460 micron wear limits.

There is a very nice joint position paper by the major manufacturers of fuel injection equipment including Stanadyne, Delphi, Bosch and others that states “It is essential that the lubricity of the fuel as measured by the HFRR test specified in ISO 12156-1 meets the requirement of a wear scar diameter not greater than 460 microns”.

The official CAT document for Diesel Engine Fluids SEBU6395-08 recommends 520 micron maximum wear scar.

That means that the US fuel requirement, if met by your supplier, “barely meets the diesel engine requirements” for some engine manufacturers and is insufficient for others.

It may also be relevant that diesel engines run in higher temp locations, such as S Fl and the Caribbean, or run under more strenuous conditions such as boat diesel engines often are, may want to meet the tighter fuel specs since these are met at 60 C which is well below standard diesel engine operating temps. This is relevant because it is the viscosity and wetting properties of the diesel fuel that provide the lubricity effects.
 
How does presumed lowered lubricity in diesel fuel "prematurely" wear out a 3208 injection pump? See post 20. Are there other possibilities such as water in the fuel or lack of good filtering in the 30 year life of these motors?

My questions aside, 2007 a scuff test study using appropriate lab HFFR equipment was conducted by A. Spicer. As noted in the study, diesel fuel was tested using a variety of Lubricity additives.

This study, as are rebuttals, can be easily found elsewhere on the Internet. The study in summary form is copied and used in the past for marketing purposes by Optilube.

NC Ski gave a very nice answer to this question, the fuel is what cools and lubricates the cam, followers and injectors in some mechanical injection systems.

I agree that there are a lot of complexities to this question, and in the study you mentioned. But you can read the study in detail and there are some compelling elements to the work. Some of the individual additive suppliers will also provide test results from reputable labs using standardized test procedures.

I spent a lot of hours reading various studies, anecdotal info, input from CAT and stanadyne (my injector OEM), and decided it is safest, especially running a lot in the Bahamas and in warmer environments, to use a lubricity specific additive with very limited other components. I was also troubled by how fuel suppliers whether by truck or at a dock, buy from a variety of suppliers based on that days pricing and are not able to provide specs on the fuel being supplied.
 
Does it make you feel better????

Nowadays most things tend to be pretty expensive and we are not always even that happy after spending money.

- a beer at expensive location over $10
- a good steal dinner for 2 maybe $200+
- a major ballgame for family of 4 near $1K
- a psychiatrist at maybe $200/hour

So how much 'happiness' do we get back from these costs?

If you spend $20 putting a can of additive into your fuel or oil and it makes you feel better just do it.
As long as it is a large recognizable brand its not likely to do any harm and maybe some good but it will make you happy.
Don't even research it or read it here - just do it as its much cheaper and faster then the psychiatrist and it will make you happy.
 
Fletcher,
I don't think anybody considers Biobor or Stabil snake oil. I always use both and never claim snake oil.
 
FWIW - this is Stanadyne....

CAS # Component Percent (w/w) 64742-47-8

Distillates, petroleum, hydrotreated light 30-50%
2-Ethylhexyl nitrate 20-30%
Naphtha (petroleum), heavy aromatic 10-30%
Ethylene glycol monobutyl ether 3-7%
Trimethylbenzene (mixed) 1-5%
Naphthalene 1-3%
1,2,4-Trimethylbenzene 0.1-0.6%
 
One other thing to note is that the ASTM D975 specs are consensus and not regulatory. The EPA does regulate sulfur, but not lubricity and viscosity. My understanding is that there are no federal regulations or laws for lubricity. These are voluntary at the federal level and that some states do regulate some aspects of fuel quality. The NIST Handbook 130 that appears as a set of fuel regulations is in fact not a set of laws but a suggested or model set that a state may adopt or some portion thereof.

I am not suggesting that the ASTM D975 specs are not widely followed, but that some low price supplier may or may not be following all of the specs and that lubricity levels in many states are purely voluntary..... and since it is so difficult to get specs from any supplier, who knows what is actually in the fuel.
 
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