low temp thermostat

[Trucku]

If your thermostat is rated for 180 degrees and your truck is seeing lower temps, you might have a bad thermostat. I don't see why you can't stay at 180 in the winter providing your cooling system is working fine and maintains the 180degrees F.
It should hold the rated temp no matter what your temp outside.

I have a 194-202 thermostat. Thats open to fully open. and I see between 197 to 202 max summer or winter.

 

[wsm41bn]

i checked the thermostat it starts to open at 180 and full open by 195.

 

[Trucku]

Is it stuck open? or maybe faulty.
It should regulate you to within that area.
I wonder why its running down so cold.

 

[wsm41bn]

i have No clue, it used to run 180 and i switched intake manfolds and carburators, and now its running 165, and its not sticking open when i boil tested it, The only change is to where my temp guage is, it used to be T'ed in on a heater hose coming off the intake, on the new manafold it is screwed right into the top of it, im still running the same antifreeze (dexcool) and its the truck that in my signature, and i also have a 7 blade fan on it.

 

[Trucku]

so its behind the thermostat in the water that would exit the engine right?

Or is it getting a reading from the cooled radiator fluid that is not even making it into the engine. I don't know much about how different flows of coolant in a radiator, but does it flow from top to bottom? I thought they all flowed that way, but I am asking anyways.

hey does your heater have a valve to stop fluid from flowing? Maybe its constantly flowing and your over cooling.had your coolant hose from the intake been bypass and is now constantly circulating cold coolant around bypassing the thermostat.
sorry i am reaching here.

Hope one of the more experienced guys chime in.

Sorry I cannot help better.

maybe Garyonekanobi will help.

 

[wsm41bn]

Yes its in the Water that exits the engine, and yes it flows from top to bottom, i got thinking this morning, about that my tank heater might have something to do with it also it might be bypassing the thermostata bit causing it to run cooler.

 

[adam123]

My dad Put a 180 In his 1989 f-150 4.9L. Has 490K on it right now, still runs along just fine. Seriously doubt your gonna See other than a little extra cushion if your cooling system isn't up to par. Or if your towing alot with your truck then I would Definitly Use the 180. I had to completly remove the T-Stat in my 1990 f-150 work truck because even with a 160 if would get too hot.