06-09-2021, 07:26 PM
I am not recommending it but vegetable oil (Castrol R) has far better sticking properties than mineral oil. I have seen components from a competition engine using vegetable oil which have been left lying around in a slightly damp atmosphere for years without showing the usual signs of rust which turn up on similar ferrous components from an engine using mineral oil. The big difficulty is cleaning off the vegetable oil before filling the engine withmineral oil for normal use. It is probably best to turn the engine over a minimum of two revolutions reasonably regularly, if you can spin it with a starter motor even better.