Bill...........Jan and I have been using Norvel Fuel....It comes in different amounts of nitro. We have 25% nitro 18% oil.
The Cox engines we have seem to like it pretty well.

Thanks, guys.  Main problem is that I don't have a really "local" source of anything, fuel or otherwise.  I CAN, however add castor to fuel that I have.  Or mix and match.  That is why I referenced the Cooper, it is 20% nitro.  Everything lse is not over 10%, basically.

I was thinking that the Cox needed castor from some long forgotten bit of memory......

I finally got me a Davis "rod setter" for the Cox engines and took a couple apart to check them.  All of them had rods that were getting loose in the pistons!

Bill <><

Thanks, guys.  Main problem is that I don't have a really "local" source of anything, fuel or otherwise.  I CAN, however add castor to fuel that I have.  Or mix and match.  That is why I referenced the Cooper, it is 20% nitro.  Everything lse is not over 10%, basically.

I was thinking that the Cox needed castor from some long forgotten bit of memory......

I finally got me a Davis "rod setter" for the Cox engines and took a couple apart to check them.  All of them had rods that were getting loose in the pistons!

Bill <><

Happens to every Cox.  If left untouched, the rod will eventually drive itself through the top of the piston.  I had a really cool picture ("had"--since lost) of one of mine that did just that, broke out a circular piece that left a hole so perfect it looked like it had been drilled.  That was my introduction to the Cox loose-rod syndrome.  A rather poor piece of engineering in my opinion.

--Ray