Buildcraft version: 7.99.12
Forge version: 2552
Link to crashreport or log (on pastebin or gist, please don't put the entire log here) : N/A
Singleplayer/multiplayer: Singleplayer

Additional information: Haven't checked anything else for missing textures yet. This was noticed with a cool oil well in an ocean.

can you reproduce with just BC? some other mod might be messing with rendering or oil

Yup, it's another mod. I'll see which one is conflicting (I only have a couple that add oil).

Found the culprit: The Disenchanter Mod. It add a disenchantment table. The missing texture showed the TileEntity name for the table, so I assumed that was causing this.

I'll go ahead and report this to them.