240 overheating with new thermostat

[JPG0511]

I recently replaced my timing chain componets. While I had the car apart I changed the belts and the termostat. Now I cant get the car to run with the thermostat in without overheating. When I take it out the car does fine. But the heater is really slow to heat up in the morning. I have tried letting it idle with the top off even tried to put some pressure on the radiator with a water hose. I checked the water pump while I had it apart and it is fine. Does anyone know the trick I am missing here?

[OM3GA]

Did you loosen the bleeder valve by the temp sensore and put coolant in until it drips out? even though this post is 2 years old but w/e haha

[rogoman]

Did you replace the thermostat with an OEM unit and did you also install the new one with the 'steam hole' on the top. If you installed a new aftermarket unit such as a Stant, then that's why you're having coolant problems; the aftermarket units are trash!!