I should know the answer to this, but want to get your input. I understand the premise of how the radiator overflow bottle works. When the radiator gets hot and pressure builds, the cap allows coolant to flow into the bottle. When it cools, vacuum builds and sucks it back in.
That said, is there any danger if the cap to the overflow bottle falls off while driving? I'm assuming not, since it's not part of the "pressurized" system. You may get a tiny bit splashing out, but nothing of concern. Am I correct in this thought?
