What should a peak water temp range to? I just got a scan guage a while ago and I have been wondering what the peak temp should be to maintain safe engine operation.
I closed off my wifes grille this winter when temps dropped below 0 and i havent opened any more than about a 4x4 inch hole at the bottom. the analog temp guage has never once budged above the half mark, but getting a digital readout on the scan guage suprised me how hot it gets.
the hottest i have seen it get is 203f. City driving usually averages around 185 +-10 depending on driving style.
The fan comes on at 206F and cools until it's below 200F.
The radiator isn't doing anything until the mid 180's when the thermostat opens.
Normal operating range is anything between those.
My '97 Civic without a grille block and with the fan disabled hovers between 199 and 203F. Highest I've seen was 213F after winding through a parking lot for several minutes to find a spot. I have an alarm on my Ultragauge that is set to go off at 210F. If I know that I'll be moving to cool it down soon I just pay more attention to it until it cools. If for some reason I won't be able to cool it down passively, I can just jump out and put my jumper back in the fan.