The point of the Texaco oil when I did it was that it had the poorest film strength and the most compressibility of the available oils. Harris Woods used Texaco oil in a small diameter tube as the spring in the landing gear
of the original woody pusher. So, the breaking is to allow the pieces that are a bit proud of what they should be can get warn down a bit and thus improve compression some. However, most synthetics have very high film strength and near zero compressibility. So, the break in period may outlast you. And the engine will finally seal up for the guy that buys the plane off of your widow. In the short term there will be extra blow by and higher crankcase pressure. It means a bit of oil in the catch tank after every flight. There should be little to none in the tank, depending on how clever your breathing system is.
So do not use a synthetic lube of any kind in the assembly of a rotary unless you are using the seals over again, then by all means use synthetics everywhere. . New seals means no synthetics until after break in.
I have no personal contact with Mobile one, but early in its production there were some problems. Now it is good enough for Corvettes. What pour weight to use I do not know. I used 40 and 50 weight Redline because it pours like lighter fluid. Not a single oil related problem.
Or, I could be completely wrong..............Lynn E. Hanover
In a message dated 6/27/2020 7:23:57 PM Eastern Standard Time, flyrotary@lancaironline.net writes: