Running without a thermostat ok?

Now I will answer those that answered the whys and how comes of the spring..... thanks! good input. RRR mine has the spring..... the reason for the question was to see if it was specific to certain engine or certain cooling system designs, you know... since your knowledge backround is so valuable, maybe you should quit giving it for free and start charging, maybe then you would come across more kind, but alas, i think you just enjoy talking down to people, here you seem to get away with it, i suspect your the guy in the town everyone call the crabby guy.