Hello everyone. Thank you for all of your help in the past, it has helped me keep my '89 manual w/265k running beautifully.

At the end of the summer after driving in high heat, my car overheated and then would continually overheat after driving only a short distance. I decided to not beat around the bush and replace the entire cooling system (Radiator, water pump and thermostat). After I installed everything it will not start. It gets ready to flip over and then I hear pronounced clunk coming from the engine and then everything cuts off before it tries again. I cannot figure out what is causing this. Can someone with the knowledge please attempt to help me? I am extremely frustrated at the moment.

Thank you,