Hi Richard
As has been said over years, NOS, New, or Used always check thermostats before installing. Surprising how often they will be slow or open way late the first time you start an engine after changing thermosts. See
http://www.mapleleafup.net/forums/sh...8&postcount=20 for I check them.
Sometimes it can also be air bubble under the thermostat which keeps the heat from reaching the body of the thermostat.
Really a bumber to watch a freshly done engine blowing boiling water out the radiator cap.
Cheers Phil