I have drained the coolant out again. Should I just do whole flush since I am already here? Can someone instruct a layperson how to do it? Or should I not mess with it? The coolant that's draining out is a bit rusty looking, considering I did install a new radiator and hoses. Or is that the way it typically looks for a 30 year old car? If I want to do a complete flush, exactly how would I accomplish that? Thanks, Lance I have a 300D 1983.

Basically I am going to check the thermostat out and make sure the arrow is pointing in the right direction.