Thermostat theory

[pontiacgp]

get yourself one of these and you can see in real time how it is working and along with a laser thermometer you can see the temperatures of the coolant...

https://www.jegs.com/p/Cool-View/Cool-View-Thermostats/2790707/10002/-1

 

[Bonnewagon]

That is beyond cool! But I would not want that on my motor. FWIW I always test a new stat before installing it and a depresssing number do not pass. Remember it has to close as well as open on cue and many don't. Still, automotive stats are pretty reliable compared to outboard motor stats that see salt water.

 

[69hurstolds]

Automotive thermostats aren't exact science. Close, but sometimes you'll see temp spike up a bit past the opening point further than others. This is kind of normal to a degree because as the engine is heating up that water that's moving very slowly or not at all through the system, the temp will continue to rise as the thermostat begins to open. On an Olds V8, the temp probe is right there next to the thermostat so there's minimal lapse of time between measuring coolant temps and what the T-stat sees.

As long as your system is sized right, and flows are good and internal surfaces aren't cruddy, your heat transfer should be sufficient in that, for example, 210 degrees vs 215 degree running temps really aren't all that significant.

But I'm in agreement with testing a new T-stat to ensure it opens/closes at or near setpoint. It's cheap to do and adds peace of mind.

 

[icr242005]

Great info. Thanks.

 

[olds307 and 403]

On older Ford's especially, you could see the gauge cycling up and down as the thermostat opened and closed. On something like the 160 thermostat is my 70S, it cycles much less, especially in warm weather as it sits at 180 to 190. It does depend on the thermostat rating and the outside temperature.

 

[Clone TIE Pilot]

Most modern cars use 195 degree thermostats for two reasons. A warmer engine rejects less waste heat for a more complete burn. This leads to less emissions and longer engine life between less combustion byproducts and boiling out block sweat.

 

[olds307 and 403]

Most modern cars use 195 degree thermostats for two reasons. A warmer engine rejects less waste heat for a more complete burn. This leads to less emissions and longer engine life between less combustion byproducts and boiling out block sweat.

Actually they are now 205 degree. Also helps big time in the heat department in the winter.

 

[icr242005]

Most modern cars use 195 degree thermostats for two reasons. A warmer engine rejects less waste heat for a more complete burn. This leads to less emissions and longer engine life between less combustion byproducts and boiling out block sweat.

Clone, thanks for the reply. I understand with higher engine temps burning off condensation (oil likes 180-210 temps) but could you explain a little more about what “rejects less waste heat” is? Thanks. Nice tread guys.

 

[Clone TIE Pilot]

Basically, to run a engine cooler, you have to dump out more energy as waste heat through the rad rather than using it for performing work. Ideally, it would be best to run a engine in the 1,000s of degrees for the most complete combustion, but material limitations prevent that. Engines run really cold for combustion, even at 205.

 

[TURNA]

Just think of it like a set of balls

at different temperatures they tighten up or loosen up