Cooling problem

[Setone]

I had a goosed thermostat so swapped it out, and used some red type anti freeze to top up the system. i used red anti freeze as that was what was already in there.

Anyway the problem is the engine warms up quicker as expected, but when the stat opens i can notice on the temp gauge that the needle drops??

So i was thinking maybe the mixture is a little to strong, so my nxt question is where is the best place to drain the system complete? bottom rad hose?

anyone had any problems like this?

 

[sideways danny]

sounds like an air lock, or a loose wire on the temp sensor to me

 

[Setone]

i might try re-bleeding it again but i've been driving the car for a week or so, coolant level hasn't dropped, plenty of heat in the car from the heaters etc.