While it works just fine pumping oil, it can only pump up to 2 blocks below it. Since BC oil is found mostly vertically, you'd need to replace the pumps every few seconds, which isn't exactly the best solution.FYI: RotaryCraft has its own pump. It's normally used to produce water for steam engines and the like, but it *should* also work on oil spouts. You'll still need a refinery from another mod to produce something that the fuel enhancer can use, but maybe BC's refinery is in a module that doesn't include anything progression-breaking?
Edit: Someone actually suggested to make a RoC addon to Reika for a pump which does work roughly like the BC pump. Reika refused it, though, as he didn't want a machine who's only purpose is to copy the function of another mod's machine. Especially BuildCraft.