any chemists here?
Im an analytical chemist, but Im not sure I have much more to offer than what Ramcharger said (not my field of expertise, I mainly work with cancer drugs).
It depends on the type of paint, but more than likely the paint wont dissolve in the oil too much
which means its going to get caught in the filter. Like Ramcharger said, if you have big flakes that could be a problem depending on the size of the screen on the oil pump pickup
the big chunks could clog the pickup screen. How is the oil pressure?