Running only Buildcraft 7.0.13 and Buildcraft compat oil refines like it should. Adding Galacticraft causes the refinery to only be able to refine Galacticraft's oil and not Buildcraft's. Buildcraft oil will sit in the refinery and nothing happens.

Edit: I realize this may be a Galacticraft issue but it did work in Buildcraft 6.4.x

Are you talking of the BC refinery or the Galacticraft one?

I don't get any problems with both...

The BC refinery. It works if I feed it GC oil.

As soon as I replace the oil source with BC oil(along with the pipes and refinery to clear it) it stops. The refinery takes in a bit of power until it is full on energy then the side pieces stop moving and it fills up with oil never making fuel.

Using forge 1448 and Galacticraft build #347. Only mods loaded are Buildcraft 7.0.13, Buildcraft compat, and the three mods for GC itself. Someone mentioned it on reddit and I reproduced it my custom pack. Figured I'd try with the bare minimum and it's still happening.

Here are screenshots of the issue:

With BC Oil:

With GC Oil:

Found my issue, watching. +1 for those experiencing. Currently trying to find a work around as in game play all I have is GC oil, my base runs on it, because of a misconfig of the world gen settings due to human error, but i digress...