quote:And, your source for this "fact" is documented, or personal Kentucky windage? The reason PAO's are the best, all the molecules are the same size and the increased thermo stability. The same can be said for synthesized esters. However ester and diester is added to PAO stocks for the solvent action to cause seal swell. Yep, that was the original reason, since PAO, alone, as a base stock, causes seal shrinkage. (leaves embarassing and unsightly oil drips on driveways, parking lots and structures, and streets - not considered good form in this age of environmental enlightenment) As more was learned about esters, and how to synthesize 'em to specifice characteristics, we have whole new classes of customized esters that also exhibit superior lubricity to PAOs, lower gel points, higher flash points, superior cleaning ability, metal bonding, and even better resistance to oxidation. The biggest farce is the hype that synthetic oils don't come out of the ground, while its true that synthetic PAO base stocks can be made from renewable sources; corn, apricot pits and other fruit stones,etc, the best base stock is a synthetic aliphatic hydrocarbon, polyalphaolefin (pao) that is a petrochemical product ( such as CPChem synfluid or SpectraSyn by Exxon). PAO's are refined from, 1-decene, decane, ethylene, propane, and a few other light hydrocarbons, all so called fossil fuels. Your last sentence belies your whole point in this paragraph. The first three molecules are synthesized from the last two molecules. Once 1-decene is reached, it's polymerized into longer chains (PAOs), and those, in turn, are further polymerized into the desired chain lengths. The source hydrocarbon to generate 1-decene is irrelevant other than economics. If seed, nut, or animal fats (all esters, by the way) become more financially viable than petroleum as a starting point to PAOs, so be it - the end result of the rest of the synthesis process to PAOs comes out the same: uniform molecular weight PAOs. Ester and Diester is primarily cracked from animal and vegetable fats and meanwhile the source of crude is still being debated, dead dinos or rotted plants? Or as one page on the Amsoil site suggests it might be continueously generated from deep inside the earth. Why would you call this a "debate"? Didn't it ever occur to you that the process is ongoing (leastways until all carbon-based life is extinguished topside) and would involve all dead matter - plant and animal? I posted in an unrelated thread a week or two ago that petroleum is the end product of decayed, dead matter from the effects of heat and pressure far underground. I believe I was wrong. It occurred to me that petroleum's a late intermediary step. I now believe the end product would be the formation of coal pockets. Nope. Make that diamonds. (Nice to know I may eventually amount to something, literally, "after all"...) Petroleum, then, to a point, is a renewable resource - just not fast enough to do us any good. Ninety percent of the used oil in this country is not being recycled and the small part that is, is not being segregated by base oil content. PAO's are safe for use in food preparation equipment and are considered kosher, EPA allows drilling lubricants (yeap you gotta lube that drill bit when drilling for oil) that are PAO based to be dumped on or in the ground or the sea floor. But no matter how safe the base oil is once you dump in the additives and use it in an internal combustion engine its a bio-hazard. That last sentence is the qualifier. As long as you're talking about base stocks, though, what you say about PAOs is applicable to Group IIIs, too (kosher, food preparation equipment safe, biodegradable, non-toxic (darned good laxative, though), etc, according to Chevron's data sheets and white papers on Group III base stocks. As for segregating used motor oil according to type, how would you propose to practically achieve that? By user assurances? (Yeah, that'll work...) Uh, are you certain about "lubing" drill-bits? I've never worked on a drilling rig, but your statement sounds a bit specious. The product data sheets and MSDS's on automotive synthetic oils I have been able to find list the POA's at around 80% with the remaining 20 percent esters and zinc and other compounds. All the aircraft turbine oil I found data sheets on was made up of ester and/or diesters(90-95%), but jet engines have different oil seals than automobiles, they use carbon seals and special oil rings. So what? It appears that higher dosages of esters in popular synthetics are not having a deletorious effect on automotive engine seals, anyway. (I'm including your vaunted M1 SuperSyn as well as the other current synthetic motor oil du jour, on this site, German Castrol 0W-30 as examples with significantly higher ester content.) As you correctly pointed out, PAOs are a marvelous development, but they are by no means the only (or "best", whatever THAT is) game in town. ("oil rings" in jet engines? but, no compression rings? amazing facts...) [ September 12, 2003, 02:24 PM: Message edited by: Ray H ]
Originally posted by Bob Woods: I[t] seems there is a lot of hot air available, but one fact [emphasis mine] shines through. Polyalphaolefin (PAO) based oils are the best, ester and diester based oils are hard on engine seals.
quote:Eiron, You shouldn't stay up so late reading these posts...it makes you really cranky.
Originally posted by Eiron:quote:Don't make me come down there & hurt you ... (D*mn! Are all these smilies green??)
Originally posted by pscholte: Is it true that Jello has a -81F pour point? I know it comes in green.
quote:Dairy products, too?
Originally posted by csandste: I remember serious discussions in the fifties over whether Catholics would go to (oh, I'm sorry it just cleaned up my grammar for me--make that h-e-double hockey sticks) for eating Jello on Friday.
quote:For real? Muslims and observant Jews both have strict dietary prohibitions against pork consumption. I wasn't aware of any prohibitions against beef. (gelatin dessert powders sold in the U.S. are labled with a "K", which I believe indicates "parve" - acceptable for consumption by observant Jews. (in other words, NO pork or pork byproducts) [ September 13, 2003, 03:05 PM: Message edited by: Ray H ]
Originally posted by quadrun1: I had a Muslim roommate in college and he wouldn't eat Jell-O for religious reasons...