You can start this at checkpoint 47.
- You will start under water with the circle vent on your right side, ignore the vent and instead go down deeper sticking to the left
- On the bottom left side will be a hatch, twist the handles then pull the lever to open it up
- Inside head left to find the sphere, pull out the cylinder and this achievement will pop
If you need more help with this you can follow my video guide below which starts at this point: