The anti-wear additive zinc dialkyldithiophosphate, or ZDDP, was essentially discovered by accident in the 1940s. Originally added to prevent rusting, engineers found it increased the anti-wear properties of motor oil by some then-unknown mechanism.


http://www.cemag.us/news/2015/03/nanosc ... e=headline

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

Science is wonderful, especially when it relates to engines...

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Yes, science is wonderful, but it has its limits. For example, it stands absolutely zero chance when pitted against mythology handed down through generations from father to son and baked to impenetrable hardness by endless repetition as "common knowledge" in forums on the internet. Everybody knows your old engine will grind itself to death unless you add this additive (no, wait, that additive! No, you're both wrong, it's this other additive!) to your oil, because the big bad government made the oil companies take out (no, wait, it was GM! No, it wasn't, it was the API! You're both wrong, it was Honda!) the zinc (no, dummy, it's the phosphorus! Shut up, you're both wrong again, it's ZDDP!).

Never mind that the zinc antiwear additives have been largely replaced by other chemistry that does at least as good a job.

Never mind that the latest API oil tests really, truly do include flat-tappet engines.

Never mind that the sudden surge in tappet failures is directly attributable to the sudden and near-complete outsourcing to China of a giant swath of aftermarket lifters.

None of that matters, because everyone with an internet connection is a qualified tribologist and petrochemist.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Thanks for the link,interesting read!

I have found this site to be quite interesting..... it is a lot to wade through, but at least the tests seem to have an objective basis for evaluation of oils.

https://540ratblog.wordpress.com/2013/0 ... t-ranking/

That's quite a read,I glossed over it but will be spending more time looking through it . I can't help but reflect on personal experiences with aviation engines. Light aircraft engines are mostly horizontally opposed air cooled designs . The two major manufacturers are Lycoming and Continental. Lycoming have the cams mounted above the crankshaft whilst Continental have cams mounted below the crank. There has been a virtual never ending discussion on cam failures on the Lycomings,Continentals seem to seldom have an issue. The design is further hampered when these engines share a common lobe between two lifters on opposing cylinders....surprise...guess which lobes fail first! The lifter design is a traditional flat tappet hyd design. ( in recent times roller lifters have been offered)The vast majority of failures stem from the low utilisation,flat tappet weekend flyer Lycomings. Same engines run in regular operations seem to hold up better. The majority of failures have been explained by many to be caused by virtually zero lubrication film left on these lobes at start up as well as high oil temps from blocked oil coolers or extended low rpm running....sorry for the ramble but I tend to connect these same issues to the typical cam failure issues in car engines. Typically,enthusiasts run V8 engines and that seems to be the majority of cases with cam failures....same cam location as the Lycomings. Typical use is weekend cruisers..low use,low power settings,prolonged idles. Throw in the constant need to have the latest most aggressive ramp rates and lifts possible for a given lifter design and the need to have higher spring pressures to tolerate these cams only aggravates the issue. BBC and 351C engines have a pretty hefty 1.7++ ratio rocker...with those spring pressures it only loads cam lobes up even more.....To my way of thinking,sure,oils are critical for any engine, but as these street engines get pushed farther in these areas the oil becomes absolutely critical to the engines survival...in some ways it's probably more demanding than a full on race engine....so guys run a solid roller on the street,lots of bragging rights there..I've got a .700" lift cam...wow....pity their heads quit flowing at .550" and probably choke after that....and the YouTube dyno run to prove you make 650++ hp for a street driven car with 50 year old leaf rear suspension is laughable...cant understand why the needle roller lifters fail with .020" lash and those poor little bearings copping 170 on the seat spring pressures!
To my way of thinking its a complete engineering approach,it's pretty easy to blame oils for,but typically they are not the sole cause of these failures in my book.

Dan,

I agree with you about "what's right" that is, people most often have an agenda and pick the data that fits how they want to go. Science is getting a hard time these days with so much pseudo-science going around and anti-science.

Brian

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Amen, Brian. Science often tells people things they do not want to hear (such as companies trying to sell products or politicians trying to get elected, or...), and so great effort is spent to try to muddy the waters or discredit scientific findings. Science is not perfect, but trusting people with clear self (usually economic) self interest over people who are really trying to learn things (and who usually don't make a lot of money) always baffles me.

Disclaimer: Yes, I am a practicing scientist.

Thanks for listening,

Lou

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Home of Slant6-powered fun machines

And now that I think about it, I have broken in 25-30 engines over 40 years with no special additives ever. Never a lobe failure or ring not seating. (But only few aggressive cams.)

After reading the the 540ratblog a few times and the listings there of how oil lubrication dropped in most cases with additives, I decided to not put in the break-in additive given to me by the local machine shop guy. He has done many thousands of engines for racing, and his work is very reliable and top notch, but I just decided to go with the old tried and true Castrol GTX that has always worked for me for break-in, in the recent /6 rebuild. We'll see.....

I have pretty much become a no-believer in the ZDDP scare with some reading on the topic. But I can only quote the reasons that I read; I have no cam test lab.

nm9stheham, your references to Castrol GTX is very interesting. Here is a response from Castrol to questions about ZDDP, a couple of quotes from it below:

http://tinyurl.com/ln7qej8





It is my impression that the reason for lower levels of ZDDP in motor oils was dictated by problems with contamination of the catalytic converters, as well as some political promises to reduce the levels of sulphur and phosphorous as part of an emission reduction deal. I have never heard of reduced ZDDP levels as a direct result of scientific advances aimed at replacing ZDDP before the then future levels in the new API standards were announced.
Another interesting aspect would be the metallurgical composition used in mechanical lifters designed after the newer API was released, compared to the older ones relying on the level of ZDDP. The level of zink is vital for binding to the steel in older lifters, modern production methods, including coating methods, may have addressed this problem differently.

Why not simply use what you feel is right?

Olaf

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Aspenized

Back to Lou's comment, after the Citizens United U.S. Supreme Court case, corporations are people too. They can now donate any amount they want to political campaigns and worse yet, corporations have pervaded our institutions of higher learning, injecting countless millions of dollars into "objective" research. That can make it hard to tell what findings are real and which are not; eminent scientists are putting out papers with skewed finding because big oil is providing their paycheck.

I point out various findings coming out of Penn State, funded by Big Oil, on the relatively benign nature of fracking, particularly the immensely toxic sludge they are pumping into the ground without any accounting to the public of the content of these chemical cocktails. The President recently mandated that they must disclose what's in their "proprietary" formulations. That's a start, but I'm quite certain they don't even know what's in most of it, they grab anything they can find in volume and throw it all together - the key is volume, they use insane volumes of water and chemicals to get that shale oil out of the ground.

Just for perspective, I'm all for oil exploration and sound energy policy, and I enjoy the fruits of their labor with gas now back down to $3/gal in CA; I just get tired of the misinformation, lack of accountability and foresight all in the name of the almighty dollar. The sad truth is that these big corporations operate out of fear of losing their market share, when in reality investment in more green technologies and transparency with the outside world would actually prove to be even more profitable to them in the long run. They're just being stupid and short-sighted.

Whew, I feel better, OK, I'll get off my soap box...

I have no doubt that ZDDP must have done something good for engine internals at some point, maybe it still does, but objective results tell the story. Addressing the previous two posts, did the Castrol that you used have any such additives? The posts of Castrol company statements suggested they had minimized them to spare the catalytic converter, but did they remove them altogether? I'm not questioning your results, I've heard many people say they use regular oil for break in.

Brian

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My grandfather used to say "You are entitled to an opinion. You are not entitled to an uninformed opinion." I think he was right.



"I'm not a doctor, but I play one on TV."

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Somebody appears to have posted a giant, long link that makes this whole thread unreadably wide. Perhaps he would be so kind as to run that link through www.tinyurl.com or www.bit.ly so as to shorten it.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

One guy I talked to said he had intended to use break in oil with additive, but forgot and put his plain old regular 10W-30 oil in there. He realized this only after about 15 minutes into break in procedure. As he was standing proudly over his engine purring at 2300 rpm, he noticed his new break in oil still on the shelf and freaked out! Later, when his engine was perfectly fine, he was glad that he had done this because he no longer lived in fear....for the purposes of full disclosure he did use assembly lube which probably had some zinc in it.

Back to Dan's cogent (always cogent and entertaining to boot) comments, I have no doubt whatsoever that companies push their products out of fear. Why does Joe Gibbs brand break in oil cost $9/qt - because you have to have it or else risk your precious engine. This is part of the folklore Dan spoke of, somebody at some point used Brand X break in oil and it worked out fine. What do they do in the next engine? Well, with that first experience having gone so well, they keep right on using the same thing out of risk aversion - I would do the same thing, don't get me wrong. But then the folklore sets in, a mixture of humans having notoriously bad memories and tendencies toward revisionist history and color commentary. Suddenly not only did Brand X work for them, but its also the best thing since sliced bread and more importantly Brand Y and other things are bad for your engine. Companies know this, they have studied human nature, and they play upon people's fears. And we all know how nervous we get just before break in, having spent a lot of time and money in a rebuild, and how good we feel after 30 minutes, when all has gone perfectly and we have a newly minted engine idling.

brian

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Thanks Dan, that was a helpful tip on URL's I didn't know those services were out there.
b

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