Bongo Fury

Sorry back again, took my bongo for it's first long run yesterday temp gauge was ok while driving but stopped in traffic for 5 min and gauge went all the way to hot for 2,3 seconds then back down to normal, pulled over 5 min later to check water, when i opened header tank water came to the top then it sucked it all back in so had to add a little water to tank all seamed to be ok after. I am first owner in this country do you think it needs a bleed or flush.
thanks
Simon.

the short answer is yes to both