ORIGINAL: Sport_Pilot
ORIGINAL: TimBle
The pharmacy grade of castor is murder to a ringed engine or a 4stroke. Build up of varnish can lead to engine failure.
Of course views will remain polarised about the use of this grade.
ABC type engines don't really care what lube oil you use as long as you use enough of it. Of course good synthetics and suitable castor work best in these.
Sorry but the pharmacy castor is the same as the A castor that the better fuel manufactures use, but better filtered and tested for toxins.
Pharmacy Castor or medicinal castor is not suitable for model engines. Use it if you like, it ownderful for gumming up engines.
if the better fuel manufacturers are using that grade and not a de-waxed castor then I'd rather run a synthetic.
its hard to tell what they use in their fuels, hence if there is castor present I opt for the lowest percentage of castor (volume) thats available.
Better grades of castor based lubes like Castrol M, Shell Advance Racing M, use hydrogenated castor oils to prevent varnish build up. They can get away with the castor in these engines because the engines of racing go-karts are rebuilt fairly often and the drivers want as little oil as possible in the fuel to get the best power per working stroke.
Medicinal Castor is not hydrogenated or de-waxed.