Multiblocks will not accept inputs

[Nercitar]

I can get the multiblock machines to activate, but I cannot get any items to go into the machines (except fuel only, in the boiler). I have tried chests, hoppers, tubes, and direct placement but nothing works. I cannot add water to the boiler or copper or zinc (ingots, dusts, etc.) to the alloy forge, rendering the multiblocks nothing but giant useless decorations. I have tried adding the input blocks to all sides, top, and bottom, and omitting them entirely. How can I fix this?