Thread: is it possible to bugger a water pump by flushing wrong way?

Hi - I decided to replace coolant in the Minister for Warfare's Holden Cruze (yes, don't laugh...it's an AWD apparently...) on the weekend. Without thinking, I disconnected the top hose and ran the hose (at low pressure) back into the motor until clear water came out the bottom (after using a chemical flush etc and allowing motor to cool down overnight). It was only afterwards that I started to think that flushing against the normal waterflow direction may damage the water pump impeller/bearings??? The water pump seems to work fine, but just wondering if this is a risk, even with a low pressure hose.

On a related issue, I was amazed how none of the websites on the internet that discuss coolant replacement highlight the risk of putting cold water into a hot engine...they all just say 'flush treatment until motor at running temp, drain and then flush with a hose and refill with coolant'...

No definately not