hi

I recently changed the water pump and thermostat in my B 230k engine,(the water pump was leaking). It all seemed to be fine, but today when i drove of for work, the temp gauge didnt stop at the normal 9 o`clock position, but raised all the way to the red area. I stopped the car, opened the hood and opened slowly the expansion tank and squezed the upper radiator hose(it was cold, meaning no water from the engine) After this, i started the car again, and the temp falled down to normal again, and has been there since.

Could this mean that i`ve messed something up while changing the water pump and thermostat? It seems to me that the thermostat didnt open until I squezed the upper hose, could it be a sticky thermostat?

I has happened only once, but i dont want to worry.

help would be appreciated

Thanks!!