Lubricity Study

[RickB]

Keith wrote:
Rickbee will just never be happy until the entire world agrees with him.

It's got nothing to do with me, I don't know why my stating simple facts about this stuff seems to disturb you so much. I could care less how you waste your money or what you put in your engine. It's your money and your engine, have fun with them.

Repeating a link to Chevron's marketing folks doesn't tell anyone anything other than Chevron is on the additives bandwagon because gullible people want to spend money. If you had posted Chevron engineering's response to the question I suggested earlier then you might be able to contribute something to the discussion.

"Ask Chevron if their diesel fuel requires*aftermarket*additives to meet engine manufacturers fuel standards in order to maintain warranty and achieve design life."

That is a very simple question and it will elicit a very simple response. You use Chevron as the example of truth and light, ask them then post their response. That way you won't be offended since the information won't come from me.

 

[Marin]

RickB wrote:Stop by Northern Lights in Seattle and ask what lubricity additive they require to keep their warranty in effect.

The head of their engineering department is a friend (he helped us determine if the boat we bought was a good one to buy) and he's one of the people who strongly recommended that we use a lubricity additive in our FL120s for the reasons I stated.

 

[Baker]

Keith, I am thinking that Oronite stuff is something that is added by the refiner or the distributor....not at the retail consumer level. I may be wrong.

 

[RickB]

Marin wrote:


RickB wrote:Stop by Northern Lights in Seattle and ask what lubricity additive they require to keep their warranty in effect.

The head of their engineering department is a friend (he helped us determine if the boat we bought was a good one to buy) and he's one of the people who strongly recommended that we use a lubricity additive in our FL120s for the reasons I stated.

So, what you are saying is this friend of yours who works at NL recommended you use mouse milk in your Lehman. Fair enough, he is entitled to his opinion regardless of his lack of*supporting data.*After all, the world's most highly regarded Lehamn guru recommends using an*additive that has been shown to reduce lubricity.

What additive does NL require*customers use to maintain their warranty?

*

 

[Marin]

Oronite (a Chevron company or division name, not a product name) seems to be in the business of making chemical components that are then sold to additive manufacturers. Here are a couple of blurbs from their website.

"Oronite manufactures and markets a number of chemical intermediates and components for use in the manufacture of additives and chemicals. We are a major producer and marketer of propylene tetramer, highly reactive polybutene, PIBSA, alkylates, specialty chemicals, sulfonic acids and specialty chemicals. Our chemical components include detergents, dispersants, and inhibitors. These materials are produced at our major manufacturing facilities in Richmond, California; New Orleans, Louisiana; Gonfreville, France; and Singapore, and distributed throughout the world."

"We use a global approach towards fuel additive development, with extensive in-house research capabilities, including engine lab and test fleets in California, the Netherlands, and Japan."

 

[RickB]

Baker wrote:Keith, I am thinking that Oronite stuff is something ...

Regardless of what it is, Chevron does not claim*Oronite is a lubricity enhancer and that is what this*thread is about.

CAUTION FF: THE FOLLOWING STATEMENT CONTAINS INFORMATION AND PRACTICES THAT APPLY TO LARGE SHIP*OPERATIONS, TO AVOID BEING OFFENDED DO NOT READ*BEYOND THIS POINT!

*There are many additives designed to modify marine fuels for specific purposes.*A common one is*added to prevent the precipitation of vanadium in the exhaust path*and is added*while loading*fuels that test high for vanadium.

There are additives that reduce cloud point or improve cetane ratings. None of these additives claim to improve lubricity because fuels meet that standard as delivered and DIY fuel blending is pointless, expensive,*and could be risky.*


-- Edited by RickB on Thursday 1st of April 2010 01:00:31 PM

 

[Marin]

RickB wrote:

So, what you are saying is this friend of yours who works at NL recommended you use mouse milk in your Lehman. Fair enough, he is entitled to his opinion regardless of his lack of*supporting data.

What additive does NL require*customers use to maintain their warranty?

*
Actually, his advice was based on teardown results on injection pumps of older engines like ours that had been run with and without lubricity additives.* However, this was twelve years ago when we were discussing this--- I don't remember any of the specifics he told me in terms of wear amount differences.*

While I agree it's just one man's opinion, albeit based on over 30 years of experience with marine propulsion and generator diesels, the fact that his opinion has been echoed by other people I've come to know who, among other things, overhaul the injection pumps of the type used on our FL120s, I can see the logic in the use of a credible lubricity additive in light of the changing nature of today's fuels.

While the fuel manufacturers and engine manufacturers obviously work closely together to ensure that today's engines and fuels are compatible, there comes a point when old technologies are no longer cost-effective to try to support anymore.* For example, the removal of lead from gasoline has resulted in problems for old engines that depended on the lead to cushion the valves in their seats.* My 1973 Land Rover has eroding valve seats today as a result of this and I know a number of people with old or classic vehicles that are in the same situation.* A number of years ago I purchased an "unleaded head" for my Land Rover that I may someday get around to installing.

So I think the notion that the fuel manufacturers are still ensuring that their fuels provide all the necessary qualities required of old technology engines is perhaps not so accurate.* The pressures they are under to meet an ever-changing set of environmental requirements make it very easy to write off the requirements of engines that, by today's standards, are Smithsonian exhibits and that would make the fuel companies' lives even more difficult if they tried to continue to meet all the old requirements along with the new.

I have no idea what the warranty requirements are for NL propulsion and generator engines since we don't have either one.

*

 

[Marin]

Here is another quote from the Oronite website. Note the last item in the list....

Diesel
Ignition characteristics affect all performance aspects of the diesel engine, including emissions, power output, fuel economy, and engine durability. Minimizing injector nozzle fouling enables high quality injection and good fuel ignition.
Oronite diesel additives (ODAs®) use a dispersant/detergent technology to reduce injector nozzle fouling. ODAs may also include additional components for:
Anti-foam
Water tolerance
Anti-corrosion
Oxidation stability
Cetane improvement
Low temperature operability
Lubricity

 

[RickB]

Marin wrote:

Actually, his advice was based on teardown results on injection pumps of older engines like ours that had been run with and without lubricity additives.* However, this was twelve years ago ...

While the fuel manufacturers and engine manufacturers obviously work closely together to ensure that today's engines and fuels are compatible, there comes a point when old technologies are no longer cost-effective to try to support anymore.*

So I think the notion that the fuel manufacturers are still ensuring that their fuels provide all the necessary qualities required of old technology engines is perhaps not so accurate.*

I have no idea what the warranty requirements are for NL propulsion and generator engines since we don't have either one.

He told you what he saw 12 years ago when the problems associated with*low sulfur diesel*were not fully understood? He told you what he saw before the engine manufacturers and refiners developed new lubricity tests and standards.*And*how relevant is this today?

Correct, the old technologies are no longer applicable.*That is precisely why there are now tests and standards to ensure diesel fuel meets the lubricity requirements of old and new engines. New engines are far more demanding than old*clunker industrial diesels so the new stuff is*far better than your Lehman requires. It is good enough for an MTU that is built like a Rolex so*why insist it is not good enough for a Lehman?

The fuel manufacturers now have standardized*lab tests and equipment to ensure that their product exceeds the*strictest*requirements. They never had this kind of quality control in the past. Given the lifespan of diesel engines, the refiners have not abandoned those units installed before 1998.

Gee, if you were talking to your friend who is the head of engineering at NL you could have asked him ... or are you just regurgitating 12 year old hearsay and subjective*appraisal?*

All I am asking anyone to do is go to the source. Ask your engine manufacturer if it requires the use of any aftermarket fuel additive to maintain the warranty or obtain performance specifications. Why not eliminate the snake oil salesmen and people like me who tap away at the keyboard supplying opinions that may only be worth what you paid for them?



*

 

[RickB]

Marin wrote:Here is another quote from the Oronite website. Note the last item in the list....

Lubricity

They don't list lubricity on the page Baker linked. If they show it somewhere else it must be for the aftermarket mouse milk trade.

 

[Marin]

RickB wrote:

They don't list lubricity on the page Baker linked. If they show it somewhere else it must be for the aftermarket mouse milk trade.

It's on their main site under the heading Products & Technolgoy, Fuel Additives.* This is the page where they list all their specific products and components.* It''s not "somewhere else."* http://www.chevron.com/products/oronite/products/fuel-additives.asp

 

[Marin]

RickB wrote:

All I am asking anyone to do is go to the source. Ask your engine manufacturer if it requires the use of any aftermarket fuel additive to maintain the warranty or obtain performance specifications.

*

That's a naive statement since the manufacturer of the Lehman Dover and Dorset engines are no longer around.* Ford of England is still around, but nobody there is going to know (or care) diddly squat about those ancient powerplants.* It'd be like asking De Havilland of Canada anything technical about the Beaver or the Otter.* They barely even acknowledge making those two planes today, and they will not provide any technical specifications about them at all (I've been involved in commercial efforts to try to get some).* To the DHC corporate mind, those products no longer exist.* This notion that companies retain all this great information about their old, long-out of production products is, for the most part, a myth.* So forget getting any useful information from the manufacturers about old Ford, Perkins, etc. engines.

You remind me of Steve D'Antonio in that your only focus is on engines that have warranties, have recent manufacturing and testing data, and so on.* So Steve's operating and servicing advice is all based on what he views as the only technology out there.* And for his perception of the marine world, he's right.* But those aren't the engines I'm concerned about.* I'm concerned about prolonging the life of engines that were designed in the 1950s using 1940s technology, metallurgy, and operating philosophies.

You're asking us-- or at least me--- to dismiss the knowledge and experience of a half-dozen or so people who have made their living designing, servicing, rebuilding and otherwise dealing with these generations of marine diesels for decades in favor of what you--- a total unknown to me--- happens to believe.* I'm not saying you're wrong--- I have no basis for saying that.* But by the same token, I have no basis for dismissing as wrong what a whole bunch of other people who, based on what I have gleaned of your experience, are every bit as knowledgeable and experienced as you and very possibly more so, have told me.* In this particular situation, I'm going to stick with the advice from the very experienced majority since I have not heard anything convincing from you with regard to the only kind of engines I care about to change my mind.

I'm not interested in what the warranty requirements of new Cats of NL engines say.* I'm not interested in what the warranties or operational data of "pre-1998" engines say because there's a big difference between what I think you mean by "pre-1998" and 1940-50.

You're welcome to regard this as ignorance if you wish.* I regard it as "paying attention" to the people who know.

*

 

[sunchaser]

WHEW!!**Thank goodness the 20+ million gallons of diesel fuel for our mine in Peru* does not have the need for one pint plastic jugs of "additive." I guess the point here is what does an old Lehman need. I hear something/nothing for the engine but definitely*something for the owner. Do any of you remember the days when detergent oil first came out? How do you spell brouhaha?

 

[RickB]

Marin wrote:You remind me of Steve D'Antonio in that your only focus is on engines that have warranties, have recent manufacturing and testing data, and so on.*

That is amusing. I got into the engineering part of the yachting world because of my experience and expertise in the operation and maintenance of the vintage diesels*that*were being installed in a modern yacht. My own 65 footer had a medium speed (400 rpm) engine that was built in the late 1930s as well as a couple of GM 71 series*auxilliaries. *Let me know if that is too modern for you.

And it was around 1998 when problems associated with low lubricity of low sulfur diesel fuel began to be understood. It is difficult to understand the present if you don't know the history of the problem. Your Lehman is not a fragile and unique piece of diesel technology that has been abandoned by the youthful chemists of today's oil refiners.

You will have to work a lot harder to find some way to discredit my opinion on the use of aftermarket additives.

If you have data to support damage to Lehman engines by fuel produced since the institution of ASTM D-975 feel free to post it. I for one would be very interested to read the findings.

Considering that the additive most highly touted by your family guru*for those engines has been shown to reduce lubricity, yet the things have not been dying like flies in the past few years should lead you to realise it is*far from naive to think that they are not safe to operate on today's fuel without the additon of mouse milk.

I don't think I have ever seen anyone fight so hard to*defend superstition and an almost religious compulsion to ignore the tribological facts.

What is even more amazing is the continued refusal to*accept that finer tolerances make a modern fuel pump more susceptible to scuffing damage from low lubricity than the relatively loose tolerances of older engines. The finer tolerances of modern engines and the higher loading of parts that require fuel for lubrication make them far more liable to damage from poor lubricity than older engines such as your Lehman.*

Show me the data to support your mythology. Rumors and 12 year old hearsay aren't worth squat. Show the data that proves modern*diesel fuel requires aftermarket additives to protect ancient or modern*diesels.*


-- Edited by RickB on Thursday 1st of April 2010 03:13:46 PM

-- Edited by RickB on Thursday 1st of April 2010 03:15:59 PM

 

[sunchaser]

In the early 1990s Californina put the commercial diesels on a S diet. *As the lower sulfur fuels hit the market, and at a greater cost, the lubricity* concerns, cries and wails came forth. At that time the company I worked for was operating a large fleet of low to high HP diesel equipment with some approaching usage of 5000 hrs per year and engine age 0 to 30 years. Issues - none. S had dropped from 500+ to about 5 ppm as I recall.*No negative effects according to our maintenance records and engine oil analysis. As usual, operator neglect was the issue with equipment reliability, not oil or fuel.

Oops I forgot to add, we used no fuel or oil* additives other than those the refineries were adding to maintain lubricity specs.

 

[Keith]

RickB wrote:


Keith wrote:
Rickbee will just never be happy until the entire world agrees with him.

It's got nothing to do with me, I don't know why my stating simple facts about this stuff seems to disturb you so much. I could care less how you waste your money or what you put in your engine. It's your money and your engine, have fun with them.

Repeating a link to Chevron's marketing folks doesn't tell anyone anything other than Chevron is on the additives bandwagon because gullible people want to spend money. If you had posted Chevron engineering's response to the question I suggested earlier then you might be able to contribute something to the discussion.

"Ask Chevron if their diesel fuel requires*aftermarket*additives to meet engine manufacturers fuel standards in order to maintain warranty and achieve design life."

That is a very simple question and it will elicit a very simple response. You use Chevron as the example of truth and light, ask them then post their response. That way you won't be offended since the information won't come from me.

I'm not upset Rickbee, I'm lauging my ass off at you. You're so easy.

*

 

[Marin]

Okay, the discussion prompted me to call my friend and here is the essence of his response. As I sort of suspected, in the case of the FL120, it's a metallurgy issue. He said the alloys used to make the injection pump plungers and bores on the pumps used on this generation of engine, which dates from the late 1940s*into the*1950s, is softer (softer being a relative term) than the alloys that came into use for these purposes later. So these components in the Simms/CAV pump are-- because of the nature of the metal used-- more dependent on a higher level of lubrication in the fuel for*longevity*than the same components in later and modern*engines. This is why the use of a lubricity additive is recommended today for engines of this vintage.

He used the engine in my Land Rover as an analogy. When it was designed in the 1960s, nobody forsaw the removal of lead from gasoline. So the lead deposits that built up on the valves and valve seats had the benefit of keeping them from sticking together and erroding which they would otherwise have done given the materials the seats and valves were made of in those days.* When the lead was first reduced and then*removed from gasoline, these materials could not stand up to the heat and lack of "cushioning" or lubrication and valve seat errosion was the result.

The "unleaded head" I referred to earlier is a re-manufactured head that has been fitted with hardened valve seats and stellite valves which are made of materials that do not depend on lead to keep them from erroding. So new materials can make all the difference in how components stand up to changes in fuel.

Of course, as RickB stated, the fuel and engine folks work together on changing developments so by the time the lead actually began to be removed the engine industry had long since moved to valve and seat materials that could deal with it, probably for a host of other advantageous reasons beside the impending removal of lead.*

For the record, I have never used Marvel Mystery Oil in any engine I have ever run regardless of Bob Smith's feelings about it.* There are definitely "snake oils" and old-fashioned assumptions and beliefs*out there, and I've always felt this was one of them.* I've never heard any of the experienced diesel people I know personally reccommend it.


-- Edited by Marin on Thursday 1st of April 2010 06:08:48 PM

 

[RickB]

Keith wrote:I'm not upset Rickbee, I'm lauging my ass off ...

Simple pleasures for simple folks I guess.*

 

[Marin]

RickB wrote:
What is even more amazing is the continued refusal to*accept that finer tolerances make a modern fuel pump more susceptible to scuffing damage from low lubricity than the relatively loose tolerances of older engines. The finer tolerances of modern engines and the higher loading of parts that require fuel for lubrication make them far more liable to damage from poor lubricity than older engines such as your Lehman.

I don't*argue this at all.* It's just common sense.* But given what I was told today about the advances of metallurgy and how they can affect engine design, I suspect that the advances in metals is what has allowed the tighter tolerances in modern diesels since the more modern materials can stand up to the*increased*heat, higher loading, and reduced fuel lubricity without damage.

This same advancement is obvious in aircraft engines.* The JT3s of the 707 era*are a far cry from today's GE-90s and 115s even though the basic theory of operation is unchanged.* It's kind of a chicken and egg thing--- we're always*learning more about how to design engines to be more powerful and efficient, but our design ideas won't work unless the materials we use to build them*keep pace with what is being asked of them.

*


-- Edited by Marin on Thursday 1st of April 2010 06:23:04 PM

 

[RickB]

Marin wrote:
But given what I was told today about the advances of metallurgy and how they can affect engine design ... our design ideas won't work unless the materials we use to build them*keep pace with what is being asked of them.

The metallurgical reference from your friend sounds suspiciously like it came from a US Army study performed just after the first Gulf war as a result of the high failure rate experienced with Stanadyne pumps that were caused by the military's desire to use a single fuel for everything from jets to tent heaters. It was discovered that the metallurgy of the Stanadyne pump plungers made them more susceptible than other units to the lower lubricity of jet fuel.

That report and the advent of other problems related to the use of low sulfur diesel in older engines with specific types of seals created the perfect storm* of fuel myths and misinformation that still rocks boats today.

The Army's problems were solved by using a lubricity enhancing additive. Everyone with a test tube and test engine got into the lubricity additive market hoping to cash in on the military contracts for diesel additives. To test the efficacy of additives the Army helped develop a standardized test rig to measure lubricity.

This is what led to the development of the BOCLE (ball on cylinder) scuffing test device that has since been replaced by the HFRR (high frequency reciprocating)* tester in use today.

Blending a lubricity enhancing additive at the refinery is how the new and more demanding standards are met. The fuel that comes from the refinery today is as good or better than the pre low-sulfur fuel that no one worried about.

Which brings us back full circle. Automotive diesel fuel has a lower flash point and viscosity than marine diesel. The lower viscosity combined with poor storage conditions creates more risk of injection component problems for automotive users than for users of higher viscosity marine diesel fuel. That recent additive report was based on automotive diesel fuel and should be viewed with a great deal of healthy skepticism. The prudent marine will not interpret its findings as a call to purchase stocks of mouse milk.

 

[Marin]

RickB wrote:




The metallurgical reference from your friend sounds suspiciously like it came from a US Army study performed just after the first Gulf war....

No, it came from the fact that he was*involved with engine design, manufacturing, and repair*starting in the 1960s.*He used phrases like "We used to make these out of [some alloy name that was Greek to me].* Then starting in [date] we changed to [some other alloy name that was Greek to me]."* He said nothing about any Army study.

 

[Keith]

RickB wrote:


Keith wrote:I'm not upset Rickbee, I'm lauging my ass off ...

Simple pleasures for simple folks I guess.*

Gotta resort to name calling? Well I can tell you why I'm laughing. Ever see the trailer for "Inglorious Bastards?" Every time I see another post from you I can't help but think of Hitler screaming "Nein, Nein, Nein, Nein!" Hahahaha!

*

 

[BaltimoreLurker]

I wonder which argument will get settled first - lubricity or single vs. twins?

 

[RickB]

BaltimoreLurker wrote:
I wonder which argument will get settled first - lubricity or single vs. twins?

My take on it is that lubricity has been deleted from list of problems a boat owner should worry about. There was a short "bubble" of problems that have been solved for nearly 10 years but the myth is fed by those who sell additives and nurtured by those who simply don't know any better.

Single vs twins? It all depends on what you have on your current boat.

*

 

[Daddyo]

I'm thinking one and a half would be best.

 

[sunchaser]

The Lehman engines of yore have taken on a cult status. Any questioning of the cult members and their*beliefs results in noises like a cat fight. It has nothing to do with lubricity, it has to do with veneration of relics, a perfectly acceptable pastime. We all just have different relics.

Marin, as a practicing metallurgist, I would not agree that modern*pistons and sleeves for CAV pumps*have "better" metallurgy. Machining tools make all the difference.

My diesel fuel experts and suppliers are adamant, today's commercial diesel meets far higher lubricity specs than fuel*from the last century. this is because of environmentla reasons which have forced newer designs.

Because boat Lehmans sit a lot, retained lubricity is an obvious question. This applies to any diesel however. Farmers in the midwest 50 - 80*years ago did all sorts of things to their fuel systems to insure a good spring startup. Maybe the Lehman expert advice is really a layup*protocl lapse*and not an operating issue??

 

[Marin]

There is a certain irony in writing something like this and then hitting a button labeled "Post Quick Reply."

Tom--- Your point about how this generation of engines may have been regarded and treated in their industrial and agricultural roles has merit. There is no way to know if this is true and if it's the source of some of the current beliefs about these engines, but it's a plausible idea.. Regarding the "Lehman cult" I"m not part of it. I'm not a fan of the Lehman engine--- I think they suck frankly, as I've stated before, and would love to have something better on our boat. But Lehmans are what we have so I have a strong interest in promoting their longevity.

The problem is that there is no definitive information out there about these engines as there is about more modern engines. The people involved in its original design are gone and Ford doesn't give a hoot about these old antiques. So other than the skimpy technical information published in the original Ford and Lehman manuals, there's nothing to go on anymore.

On the one hand you have people like RickB who maintains that today's diesel fuel still provides the required lubricity for these old engines despite the changes in the formulation of the fuel. Then there are the anecdotal story people who talk about how they ran their Lehmans or whatever for ten zillion hours on regular fuel with no problems. I tend to discount those one-off experiences not because they aren't true but they could be exceptions or, if they haven't torn the engine down to examine them, what's to say there isn't excess wear. I know someone who had a great experience with a Yugo but I wouldn't use that as definitive proof it was an excellent car. So I tend to not base my decisions or judgments on anecdotes.

Then on the other hand there are people who I regard as very experienced and knowledgeable about diesel engines who cite what certainly seem to me to be credible reasons why these old things benefit from a lubricity additive in the current fuel environment. These range from the friend I've mentioned who's been involved professionally in diesel engine design and manufacturing his whole life for a company with a high reputation in the marine industry to a fellow I met the other year who before he retired made a lot of money owning and managing a large maintenance, repair, and overhaul company in England that specialized in diesel engines including the base engines for the FL120 and FL135.

During a film shoot I directed with one of their brand new locomotives I had occasion to talk with a maintenance manager for the BNSF railroad here in Seattle. This had nothing to do with boat engines--- I really like trains. But in describing to me what's involved in getting the maximum life from their locomotive engines he talked about all the additives they put in the fuel. This is apples and oranges since their fuel is considerably different from what we use in our boats, but the point is that here is a major transportation company that regards fuel additives as a necessary part of their operation.

And finally there is our local diesel shop which has been in business for many years and has serviced, repaired, and worked on countless FL120s and FL135s.

None of these people would have remained in business, much less been very successful in their business, if they based their practices on hearsay, myth, old farmer's tales, and so on. If they espoused practices that resulted in problems for their customers, their businesses would have faltered sooner rather than later. So at some point I--- who readily admit to being totally out of my realm of knowledge on this subject-- have to believe and trust someone. And in matters like this, I'm going to go with the people who's professional careers have depended on their knowing what they're talking about.

Rick's point about the whole lubricity thing being a marketing scam is well taken, but in the case of most of the people I've taken advice from,they aren't in the business of selling additives so they've got nothing to gain from my using them. They are simply giving me advice based on their experience.

Now nobody I've talked to has said that without a lubricity additive an FL120 will self-destruct 15 hours, 27 minutes, and 10 seconds from now. They say they will likely go for years with no problems, decades even given the minimal use most of them in boats get. But given the expense of an injector pump rebuild, I would just as soon put that off for as long as I possibly can. If using a lubricity additive means that the pumps go for another two hundred or five hundred hours or a thousand hours or whatever, it's worth it to me.

The bottom line for me is, outside of a handful of people on this forum, I've not heard anyone I've dealt with in the diesel engine business around here say "You don't need to use a lubricity additive in your Lehmans because today's fuel provides all the lubricity it needs." Everything I hear from every professional I've talked to about this has been exactly the opposite.

-- Edited by Marin on Friday 2nd of April 2010 01:13:41 PM

 

[sunchaser]

Marin

I have no dog in the fight here. I use Startron with every fillup if the fuel will be stored for over a year, which in my case at least 500 gallons is always a year old. As I've stated at least 3 times on this thread, my company is a hugh diesel consumer and we work with most of the fuel suppliers around the world. All additives we use are refinery added. By all means use "mouse milk" to keep the CAV pump working right. Remember though, the old engines and related fuel systems that have seals, O rings and gaskets are not compatible with today's modern elixirs. Can you believe that*many of today's more popular diesel fuel additives are*nothing more than motor oil cut with biocides and*methanol? And methyl alcohol is dynamite to the above mentioned engine parts.

-- Edited by sunchaser on Friday 2nd of April 2010 01:43:35 PM

 

[Marin]

Yeah, all one has to do is go the local auto parts store, particularly the chain stores like Shucks (or whatever it's called now) and look at all the additives that say they do this, that, or the other thing to realize that most of them are probably the same ingredients with different packaging and claims. And what is it that FF says he's heard Mystery Oil is? Diesel fuel with red dye and an aromatic to make it smell different?

But while I've got your attention Mike, here's an unlreated mystery I've wondered about for decades that perhaps you can explain for me since you're in the business. When I bought my 1973 Land Rover new I obviously wanted to do what was best for the engine. At that time, STP oil treatment was promoting itself heavily so I tried it. Put in a can per the directions (with the engine running). Then I drove home. Immediately, whenever I started out under engine load from a stoplight or whatever, the engine would knock. Badly. So on the way home I stopped at an auto store and bought some new oil and changed the oil when I got home. No more knocking. But the claims for STP were so compelling I decided to try it one more time.

Same exact deal. Put the STP in and immediately the engine would knock under load. Changed the oil when I got home, no more knocking. That ended my experiment with STP forever and I've run that engine (and all our other vehicle engines) on un-altered Castrol 20-50 ever since.

But try as I might, I have never been able to come up with a plausible explanation of why the addition of STP to the lube oil made the engine knock. Any ideas?

 

[RickB]

Marin wrote:

But try as I might, I have never been able to come up with a plausible explanation of why the addition of STP to the lube oil made the engine knock. Any ideas?

Don't know who Mike is but I'll jump in with this one. A new engine puts more oil in the combustion chamber than one that has been run in, and less than one that is worn out. Oil lowers the octane rating.

STP probably allowed enough oil to stick to the cylinder walls to lower the octane enough to knock. It sounds like the engine was pretty close to the knock limit anyway and a very small amount of oil was enough to reach the tipping point.

*