Re: Synthetic oils

[Doug Davis]

Ok gang! heres what I found out talking with the Amsoil Tech. rep this morning. Amsoil no longer produces an "aviation" oil.  Was it any different? yes, a little--didn't elaborate.  Does Amsoil suspend lead and carbon deposits better than ordinary oils? yes, definitely, then is removed by filtering.  Why did Amsoil decide to stop marketing Aircraft oils?-- because of the high liability cost /vs.market potential.  Then at this point, sensing a reluctance to talk aircraft, I switched tracks.  Consider the automotive market.  If there were heavier than normal lead deposits, (which are heavy) how long would An Amsoil product hold them in suspension, and would they ultimately settle? They would hold heavy lead deposits in suspension much longer than conventional oils, but would eventually settle to some degree, but only the heaviest of the deposits.  Uh--ok, if an engine called for straight 20, 40, or 50 Weight oil depending on the time of year, what would you recommend?  A multi-viscosity Amsoil pure synthetic of 10/40, or 20/50. Ok! now for some "Dougie Analysis"  Pure synthetics are better overall, than conventional oils.  And that from the standpoints of contaminant suspension (and removal through filtration), non-breakdown properties due to high heat levels if attained ( highly unlikely, since we have air cooled engines and reduced friction through the synthetics), elimination of "dry starts", elimination of stuck valves, elimination of harmful carbon/lead and crystallized deposits behind rings.  Leaving the rest of the problems to be solved by the owner through proper leaning and shut down procedures.  Still think however, that oil change intervals should be at the 50 / 75 hour level, or every 6 months regardless.  (4 months with conventional oils) The additional 12-15.00 per change represented by "pure" synthetic oil, I think is great "insurance" and worth the additional expense.  You all know the old adage: " pay me now or pay me a lot more later".  One thing is for sure. If you want the best results from the synthetic of your choice (if you so choose) you need to flush your engine by obtaining one can of Amsoil "engine flush", and add to your present oil.  Run at 1000 rpm's for 10 min. drain, then add the synthetic.  This process gets rid of the contaminants in the engine, and lets the synthetic do it's job of keeping the engine "clean" without having to remove all the deposits first. What ever your choice, Fly happy!! Doug P.S. Even though synthetics have a much lower pour temp. and appear to have much less viscosity, they form a molecular "bond" between rings and cylinder walls, causing greater power and fuel efficiency, and more stable oil pressure, due to non-breakdown properties.