Originally posted by: Pacfanweb
Originally posted by: Zenmervolt
Originally posted by: Pacfanweb
ZV, you can shut it off safely before it's warmed up, as long as you're going to restart it soon and go ahead and get it hot.
What's not good is shutting it off after it's halfway warmed up, or just after it's to operating temp. The engine has to run awhile at operating temp to evaporate the condensation.
BTW, engine operating temp is measured by the coolant temp, don't know if that was a typo or not.
Not really. The engine is at operating temp right when the thermostat opens and allows the coolant to start flowing through the radiator. That's just a bit before the coolant itself is at normal temperature.
After a while, the engine and coolant are roughly the same temp, but on initial startup the engine reaches normal temperature first.
Of course, that's all a technicality.
ZV
Well technically, that could be right or wrong. Since the coolant is always flowing a bit, it's not like there's hot water in the engine and ice cold coolant in the radiator.
Plus, if it did work the way you said, the t-stat would open, then shut immediately when the cold coolant rushed in.
Put it this way. I doubt you'd see your coolant temp gauge drop when the t-stat opens, if your cooling system is working normally. And if it did, it wouldn't drop much, and wouldn't be dropped for long.
As you said, it's a technicality, and either way you're safe to shut the engine off for 15-20 minutes at a drawbridge or train crossing before it's warmed up completely, again...as long as you're going to restart and drive awhile.