Oil and Fuel issues
There's something about using AVGAS 100 LL on our Yaks: this 100LL contains 0,56 grams of tetra-ethyl lead per liter. That is eight times more than the mogas fuels in ancient times. And this is a problem when a radial engine does not run very often. In that case water stays in the oil instead of getting boiled out. The combustion byproducts of the lead in Avgas 100LL chemically react with that water and make an acid. This of course is very corrosive.
So: mogas is perhaps not that bad. Anyway, you should change the oil quite often for this reason. Of course it would be nice if we could use semi-synthetic multigrade oils like the W15W50 but it is still not known if this is acceptable. Tests are going on.
The W100Plus may be an excellent choice for a good oil WITH a corrosion inhibitor
