SirSengir/BuildCraft — pull request #85 by AartBluestoke (2012-07-11 06:35:34+00:00)
Title: IronEngines (combustion) have an inventory slot also, for buckets.

For some reason redpower pneumatic tubes can deliver lava buckets to a IC2 geothermal engine, and BC Steam engine but do not interface with a Combustion engine; i believe this is the fault.