I've had mixed experiences with Combustion Engines since I started playing FTB - they're cheap, portable and easy to set up so they are nice for temporary setups, but they have cost me a lot of resources while I've been learning how they work. I feel that I have a pretty good handle on them now and ought to be able to trust them to run for extended periods without incident, but last night I had a set of four engines running on a full-size quarry and they blew up. I'm trying to figure out why.
The setup I had was three combustion engines surrounding the quarry, and a third one powering a pump to keep them all cooled. I don't know if the fourth is efficient/necessary, but the pump could never keep the other three engines filled if I was only using redstone engines so I just decided to use a more powerful one. With the combustion engine powering the pump, all four engines are topped up with water 100% of the time.
Anyway...there are (were) four engines, all cooled by the one pump. I made a large infinite water source beneath the pump, about 12-15 blocks (not sure exactly, but it expanded far away from the extractor pipe) so it wouldn't be able to run it dry as it can do if you use a traditional 2x2 infinite water source.
The engines were all filled with fuel a couple of hours before the "event" - the engine powering the pump had an extra bucket in the fuel slot to ensure that it would not run out of gas before the others. This setup should be perfectly safe, and I have dug out a number of quarries and powered a tree farm for days using the same configuration without any issues.
So now we move onto the circumstances of the explosion. The quarry was running about 500 blocks away from my home base, and I had a portal close by for quick transport. I wanted to go and check on it as I knew it was nearing bedrock, and I discovered that my portal didn't work. Bad news...so I grabbed a bunch of chests and barrels and flew over there. I found, as expected, that the engines had exploded and my collection area was in a shambles. (For the record, I resolve to encase all combustion engines in Obsidian from now on, regardless of what I learn from this topic.)
Now my understanding of Combustion Engines is that they can/will only explode if they overheat or if the power they produce is not consumed. The quarry was not finished, so I don't think the cause of the explosion was power consumption - it had about half of the bottom layer to go. That IS a bit suspicious and perhaps it did stop, but from what I can tell it ought to have mined out the entire bottom layer so the floor was nothing but bedrock before it stopped consuming power.
So the only other option in my mind is that the pump somehow consumed it's water source and stopped cooling the engines. I don't think that is a likely option either, but it seems more feasible than the quarry stopping before it finished the final layer.
Is there anything I'm missing? I don't have any screenshots or anything (not that they'd be of any use now), but perhaps someone with more knowledge about combustion engines can tell me whether there is a third condition I ought to be aware of. For now, I'm completely stumped and don't want to risk using Combustion Engines again until I find out why these ones blew up on me!
The setup I had was three combustion engines surrounding the quarry, and a third one powering a pump to keep them all cooled. I don't know if the fourth is efficient/necessary, but the pump could never keep the other three engines filled if I was only using redstone engines so I just decided to use a more powerful one. With the combustion engine powering the pump, all four engines are topped up with water 100% of the time.
Anyway...there are (were) four engines, all cooled by the one pump. I made a large infinite water source beneath the pump, about 12-15 blocks (not sure exactly, but it expanded far away from the extractor pipe) so it wouldn't be able to run it dry as it can do if you use a traditional 2x2 infinite water source.
The engines were all filled with fuel a couple of hours before the "event" - the engine powering the pump had an extra bucket in the fuel slot to ensure that it would not run out of gas before the others. This setup should be perfectly safe, and I have dug out a number of quarries and powered a tree farm for days using the same configuration without any issues.
So now we move onto the circumstances of the explosion. The quarry was running about 500 blocks away from my home base, and I had a portal close by for quick transport. I wanted to go and check on it as I knew it was nearing bedrock, and I discovered that my portal didn't work. Bad news...so I grabbed a bunch of chests and barrels and flew over there. I found, as expected, that the engines had exploded and my collection area was in a shambles. (For the record, I resolve to encase all combustion engines in Obsidian from now on, regardless of what I learn from this topic.)
Now my understanding of Combustion Engines is that they can/will only explode if they overheat or if the power they produce is not consumed. The quarry was not finished, so I don't think the cause of the explosion was power consumption - it had about half of the bottom layer to go. That IS a bit suspicious and perhaps it did stop, but from what I can tell it ought to have mined out the entire bottom layer so the floor was nothing but bedrock before it stopped consuming power.
So the only other option in my mind is that the pump somehow consumed it's water source and stopped cooling the engines. I don't think that is a likely option either, but it seems more feasible than the quarry stopping before it finished the final layer.
Is there anything I'm missing? I don't have any screenshots or anything (not that they'd be of any use now), but perhaps someone with more knowledge about combustion engines can tell me whether there is a third condition I ought to be aware of. For now, I'm completely stumped and don't want to risk using Combustion Engines again until I find out why these ones blew up on me!
