QUOTE(Travis Neff @ Aug 20 2009, 09:05 PM)
These open at 140 celcius (283 degrees F), I should have paid attention to that.
Travis is correct. I got these out of the heating system of a type III as a friend told we ther were the same. They appear the same as a Type IV engine thermostat and are marked 140. They do not open in boiling water and in my oven did not open until after 300 F. It must be 140 C = 283 F which is way too hot for a engine thermostat.
All money has been refunded. Sorry for the problem.