Hi,
Nepotisim, thanks for your explanation, but I was refering to preservation oil as stated in my previous post.
I guess I need to explain my question since it seems not clear.
The goal of wet cranking after new engine installation is to purge preservation oil from the entire engine fuel system (through fuel nozzles). If you open LP fuel filter drain as mentioned by Swedish Steve, part of the preservation oil will come out from the drain filter, the rest of the preservation oil will stay inside other engine fuel components (downstream LP fuel filter).
As I said before I am not familiar with RR engines but I assume its engine fuel system is not completely different than other systems (GE or PW...)
Thanks
Regards