| Slant Six Forum https://slantsix.org/forum/ |
|
| Nanoscale Mysteries Behind Anti-wear Motor Oil Additive https://slantsix.org/forum/viewtopic.php?t=57331 |
Page 3 of 3 |
| Author: | madmax/6 [ Thu Mar 26, 2015 7:04 pm ] |
| Post subject: | |
I use zddp additive. I use 10 30 Mobile 1 oil. I re-torque my head several times a year. I have zero engine failures and 10 records. Tore down motor after over 500 11 second passes and replaced nothing but gaskets. Gonna keep doing all the things that don't need to be done. |
|
| Author: | SlantSixDan [ Thu Mar 26, 2015 9:10 pm ] |
| Post subject: | |
I don't think anybody is going to argue against using appropriate break-in lubricants. Certainly I'm not. |
|
| Author: | Dart270 [ Fri Mar 27, 2015 4:55 am ] |
| Post subject: | |
I was not suggesting folks shouldn't use break in lube for the cam. I do and I will. I was just musing that it *might* work without it. Lou |
|
| Author: | nm9stheham [ Fri Mar 27, 2015 6:56 am ] |
| Post subject: | |
I use the lubriplate on other valve train parts but not on flat lifters. BTW, I ran across this on how ZDDP works; interesting info to me. It is also interesting that the original formulations contained <1% ZDDP and the additives raise it to the 2-15% range. That tells me that not a lot is needed and the additive are somewhat excessive; perhaps they displace TOO MUCH base oil and other stuff. The reference in this short paper is to film strength enhancement by ZDDP, and film strength is exactly the testing that is being performed in the test ranking in the 540ratblog referenced. http://www.ahcso.com/pdf/zddp_article.pdf And Madmax, my experience with oiling failures with Mobil1 showed pretty much the same outcome as you are finding: no wear even with 0 oil pressure sustained for a few minutes on a rally stage. |
|
| Author: | olafla [ Fri Mar 27, 2015 7:37 am ] |
| Post subject: | |
The zddp article was interesting to read, nm9stheham, but it is 10 years old, and was written at the beginning of the zddp debate. It addresses the diesel engine oils, that at least for the car engine market in Europe has changed drastically, among other regulations there are now mandatory particle filters to be taken into consideration. (those in turn have raised some new health issues, as it seems we breathe all the smaller, foul particles deeper into our lungs than before!) I am not familiar with the truck diesel engine oil situation. As I wrote earlier, almost all the oil companies now have oils with high ZDDP content for 'classic engines'. Olaf |
|
| Author: | SlantSixDan [ Fri Mar 27, 2015 10:15 am ] |
| Post subject: | |
Very detailed discussion and analysis of all these issues in http://www.widman.biz/uploads/Corvair_oil.pdf . |
|
| Author: | nm9stheham [ Fri Mar 27, 2015 2:07 pm ] |
| Post subject: | |
Thank you Dan; I am trying to find more info to read. I appreciate it. And Olaf, the article may be 10 years old, but I found the description of how the zinc works to form a stronger film under localized pressure to be the main point of my interest. |
|
| Author: | '67 Dart 270 [ Fri Mar 27, 2015 3:36 pm ] |
| Post subject: | interesting article, Dan |
...I was particularly interested by the "elasto-hydrodynamic lubrication" bit, where the oil, under extreme pressure, becomes a solid and damages the bearing surface. I believe what they are saying is that the oil films under extreme pressure between surfaces, exhibit quasi-solid properties, they essentially behave like amorphous solids (glass) under these conditions. I didn't know motor oil did that, cool stuff. brian |
|
| Author: | '67 Dart 270 [ Sat Mar 28, 2015 9:15 am ] |
| Post subject: | clarification... |
I meant to say, that I didn't realize the engine could produce enough pressure to make oil's viscosity rise so extremely as to act like a solid...amazing (to me at least, but I'm easily entertained). brian |
|
| Author: | '67 Dart 270 [ Sat Mar 28, 2015 9:22 am ] |
| Post subject: | hydrodynamic lubrication in action |
My brother had 413 in his Superbee that spun a bearing or had a bad one. When you first started it up it knocked really loudly for just a second or so but as soon as the oil pressure rose it went away - hydrodynamic cushion at work. He drove it that way for a good while before pulling the engine for a rebuild. brian |
|
| Author: | Dart270 [ Sat Mar 28, 2015 11:57 am ] |
| Post subject: | |
In most cases, if you shear load/force a liquid hard or fast enough, it will act at least partially like a solid (with elastic properties as well as viscous properties). Liquids with larger or more strongly associated molecules exhibit this at lower shear forces as compared to liquids with small or weakly associated molecules. Here is a site that might be intelligible and appears to be decently written on this topic. http://en.wikipedia.org/wiki/Viscoelasticity Lou |
|
| Author: | Sam Powell [ Sat Mar 28, 2015 4:54 pm ] |
| Post subject: | |
Quote: Very detailed discussion and analysis of all these issues in http://www.widman.biz/uploads/Corvair_oil.pdf .
I read every word of this twice, and here are several takeaways:1. If this guy is a native Bolivian, his English writing skills are amazing. I feel a little like the guy who was fleeing the pursuing black dressed, masked swordsman in Princess Bride. The longer I read the more I found myself saying "Who is that guy? He is good!" 2. There is way more to this oil thing than I ever thought there would be! 3. Additives can throw off the somewhat delicate balance in the careful formulation of a specific oil for a specific purpose and make the oil quite destructive to the engine. 4. I will never buy oil from a big box or chain store again. 5. Next time I go to buy oil for the Dart I will read this again and take notes with me while shopping. 6. Modern full synthetics have probably the best balance of qualities for the most varied applications, but you still must match the viscosity with the temp and use. They are the highest achievement of modern oil manufacturing to date. 7. I will stay away from synthetic blends. The term is used too loosely, and can cover a lot of sins in cost cutting measures. WOW!!! My mind is still reeling. And now, one last comment. In the old days (really old) we were taught to test if the oil needed changing by squeezing a couple of drops from the dipstick between two fingers very hard. If the fingers looked dry after separating them, change the oil. If they still looked oily, the oil had some life left in it. Also, the sniff test was applied. Old oil had a particular smell. If it smelled "bad", time to change. Now, while not as scientific as sending the oil to a lab, I can see that this old folk lore had some scientific basis. This article shed some light on what these "tests" were looking for. It was the best we had at the time, and while not great, was far from superstition or baseless guesses. Something of substance was behind it. That said, I recognized a number of dumb things I did regarding oil choice and use in the past. Dan, Thanks for posting this link. I wish there were an appendix of abbreviations and acronyms as well as a chart in Fahrenheit. Sam |
|
| Author: | Old6rodder [ Sat Mar 28, 2015 5:24 pm ] |
| Post subject: | |
Quote: Very detailed discussion and analysis of all these issues in http://www.widman.biz/uploads/Corvair_oil.pdf .
And in reasonably layic language. Thanks.
|
|
| Author: | SlantSixDan [ Sat Mar 28, 2015 9:05 pm ] |
| Post subject: | |
Quote: In most cases, if you shear load/force a liquid hard or fast enough, it will act at least partially like a solid
Choosy science teachers choose Oobleck!
|
|
| Page 3 of 3 | All times are UTC-07:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|