In Minecraft, when you use a bucket to get water, or you dig out a block on a shore line, most of the time the water around it fills to turn it into a normal water block, this way a small pool of water can be used as an infinite water source (e.g. a 3×3 well with water placed in all 4 corners, the center block will always refill).
With Combustion Engines in the BuildCraft Mod, you can cool them down with water from buckets or through pipes. I am wondering: if I had a block of water which always refilled when I would use a bucket, and I was to draw water from that point with a pipe for a Combustion Engine, would the water still be infinite?
Edit: I do not use Feed The Beast, but I have installed BuildCraft Stable 6.0 manually.
Best Answer
Depending on the pump you use. The Redpower pumps suck up water blocks, eventually draining a water source entirely, but IndustrialCraft pumps are not so "efficient". They will only empty a single water block, so as long as you have an infinite water source, they will pump the fluid indefinitely. A good way to think about it is an IndustrialCraft pump will function the same way as a bucket - if you have an infinite water source, the pump will continue without issue.
Thermal Expansion have an alternate option, called an Aqueous Accumulator. It's a little expensive to build, but this is the machine you are looking for. All you require is a small infinite water source and the Accumulator will draw from this indefinitely.
Here is the recipe for the Accumulator.