No Castor?

John, are talking about using pure synthetic? From what little I understand about lubricants, their reaction to stresses and temperature effects, I think castor may do one thing to protect the engines that no others do; and that is building a protective varnish very early in the life of the engine that keeps the ball and socket from wearing. As for the rest of the rotating assembly, I'd be willing to guess synth works just fine. The operative term in my statement is "guess." Another guess is that switching a properly run-in engine to pure synth will run fine for a lot longer than a new engine broken in with it. This being because the varnish in the piston and rod will hold up for a while before it wears off. I think where synth turns to carbon, castor turns to varnish.

Now please remember I, Rockin' Rusty, am guessing. Do not make any decisions based on what I have just said. I have conjured my guesses from numerous posts by other forum members, including at RCG, who may or may not know what they are talking about. But they sure do make it sound convincing.

Really John please do not do it for long or you will ruin your engines.
Just ask Godsey what happened to his first cox!

My first two actually. Rusty is spot on. Compression is lost. Ball and socket wear was accelerated. Crank was fine though. I ran one of those on good fuel and castor build up corrected it to an extent.