The spring goes into engine side. Use a Toyota thermostat as they have a small vent that bleeds air.
The other thing you did not mention is the waterpump. When thermostat opens you should be able to feel the coolant running through the hose (carefull, it's hot). If no flow, then waterpump is suspect.
You should also drain and flush the cooling system. It is best to use curved factory type hoses rather than the flex type.
Tuesday, January 13th, 2009 AT 1:18 PM