All, The multi viscosity oils are a product of the car industry. Cars are at average not driven more than for a few minutes to their destination. The engine never fully warms up in such use case. To allow this kind of abuse and still meet the emission standards, Multi -Vis-Oil has been introduced. Multi viscose oil is good and maybe best in water cooled engines, where overheating of cylinder heads or other engine parts rarely become an issue. In an air cooled engine, under high outside temperatures, I trust single grade oils. Multi grade oils are made from a mix of a low viscosity stock oil mixed with additives that artificial keep the viscosity in the advertized range. These additives can make up to ten percent in volume of the oil. All no problem as long as the temperatures are kept low - like in water cooled engines. But in in a hot environment, the oil might just break away. All oil manufacturers agree on this part: single grade oil can take a bit more abuse. Secondly, single grade oil sticks more to the inner parts of the engine, providing corrosion protection. Multi grade oils don't do this as much, since they are based of a lower viscosity. They just strip off the engine parts much easier, exposing the metal to corrosion. This problem is known and the manufacturers are mitigating it with another set of additives for corrosion protection. But in general, all oils that are approved oils should be good enough for our engines. I just find it a bit expensive to throw away that high priced oil every 20 hours. Hartmut http://www.ercoupe.info
To: [EMAIL PROTECTED]; [EMAIL PROTECTED]: [EMAIL PROTECTED]: Thu, 31 Jan 2008 20:20:12 -0500Subject: Re: [ercoupe-tech] Engine Oil Hi Bart,I formerly used Aeroshell 100 all the time. Then my A&P/IA suggested that I switch to Aeroshell 15W50. He said that it was a much better oil, and he'd rather that I use it in the engine that he rebuilt for me. I respect his opinion and his experience, so I switched. Later I heard a talk about aircraft lubricants from a guy in the industry, (not an Aeroshell guy) and he said that the only reason oil companies still sell straight weight oils like Aeroshell 100 is because today's pilots think they should use the same oils that their fathers used. (Funny - that's exactly why I was using Aeroshell 100!) He said that there is no reason in the world that anyone should use a straight weight oil in an airplane engine today, regardless of the vintage of the engine. He had lots of wear data, corossion data and rust data (and pictures) to back up his claims. He convinced me. Actually he recommended full synthetics, but I don't use that type of oil because I wouldn't be able to afford to change it every 20 hours. (Yes, I know you don't have to change synthetic oil every 20 hours, but all oils collect dirt, and the oil filter collects junk, and I don't want dirt in the oil, and I want to look in the oil filter every 20 hours regardless.) If you change your oil every 20 hours, you should never have a problem with oil quality, regardless of which type or brand you use, as long as it's approved aircraft oil.Just my opinion. Wayne-----Original Message-----From: robertbartunek <[EMAIL PROTECTED]>To: [EMAIL PROTECTED]: Thu, 31 Jan 2008 9:32 amSubject: [ercoupe-tech] Engine Oil I am currently using Phillips 20-50 in my engine that has about 60 hours on it. I have been asked if I want to start using Aeroshell 100 at my next oil change. The airplane is located in Florida and I am told most people here use the Aeroshell. I don't think it is a good idea to switch viscosities, or so I have been told in the past. What is the current thinking on this subject and does anybody have a preference for either engine oil?Bart More new features than ever. Check out the new AOL Mail! _________________________________________________________________ Connect and share in new ways with Windows Live. http://www.windowslive.com/share.html?ocid=TXT_TAGHM_Wave2_sharelife_012008
