I have a Peat Bog and Turbary and I powered it using a fuel-powered Combustion Engine cooled with an Aqueous Accumulator, but I still wound up with a giant crater. What happened?
Basically, what happens is that the Peat Bog and Turbary don't need the incredible amount of power produced and it goes back in the Combustion Engine. This causes it to overheat no matter how much coolant you have in the engine. One of the perks of using Redstone Energy Conduits from Thermal Expansion is that they will automatically dissipate unused MJ out of the pipe instead of ejecting it back into the engine. But, for low energy machines in the early game, you should most likely use Peat-Fired Engines once you get peat going (you could manually farm it if you need to).
a few reasons for this:
- Chunks unload/reload/etc (this will cause your water source to disappear when pumped)
- Not enough work for the engine causes heat to rise very fast, if you arent pumping enough water, or if previous problem happens. kaboom.
- lag can cause the tick calculation to go a little bit wonky and the engine heat will just spike, and kaboom.
solutions, use weaker engines or a different power source (electrical engines never explode)
as mentioned in the other answer, Thermal expansion is probably your best source when using Buildcraft energy is redstone energy conduits/cells.