If you have replaced the thermostat with an aftermarket one, it is probably causing the hot running.
Buy a Honda part.
Also, plain water does not provide as much boil-over protection as coolant. AntiFreeze has a higher boiling point than water....and the surfactants in the coolant allow it to coat the metal, providing better heat transfer.
https://en.wikipedia.org/wiki/Surfactant
Buy a Honda part.
Also, plain water does not provide as much boil-over protection as coolant. AntiFreeze has a higher boiling point than water....and the surfactants in the coolant allow it to coat the metal, providing better heat transfer.
https://en.wikipedia.org/wiki/Surfactant