Technically, redstone engines can explode unless at some point they changed that. It just isn't very likely since even a wooden pipe will be enough for it to output its energy buffer before exploding. When fully warmed up, you'll notice that redstone engines flash yellow/red - that means they're always on the edge of exploding, but when they output their energy they go back to safe levels. It's been a very long time since I actually tested, but it used to be that if you left a redstone engine on with nothing connected to it long enough it would explode.
If your steam engine is seizing up, that means if it had been a stirling engine instead it would have exploded. Better to have the headache of restarting it occasionally than coming back to a crater.
If your steam engine is seizing up, that means if it had been a stirling engine instead it would have exploded. Better to have the headache of restarting it occasionally than coming back to a crater.